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1_batch_xml2abc.py

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+ORI_FOLDER = ""  # Replace with the path to your folder containing XML (.xml, .mxl, .musicxml) files
+DES_FOLDER = ""   # The script will convert the musicxml files and output standard abc notation files to this folder
+
+import os
+import math
+import random
+import subprocess
+from tqdm import tqdm
+from multiprocessing import Pool
+
+
+def convert_xml2abc(file_list):
+    cmd = 'python xml2abc.py -d 8 -c 6 -x '
+    for file in tqdm(file_list):
+        filename = os.path.basename(file)
+        os.makedirs(DES_FOLDER, exist_ok=True)
+
+        try:
+            p = subprocess.Popen(cmd + '"' + file + '"', stdout=subprocess.PIPE, shell=True)
+            result = p.communicate()
+            output = result[0].decode('utf-8')
+
+            if output == '':
+                with open("logs/xml2abc_error_log.txt", "a", encoding="utf-8") as f:
+                    f.write(file + '\n')
+                continue
+            else:
+                with open(os.path.join(DES_FOLDER, filename.rsplit('.', 1)[0] + '.abc'), 'w', encoding='utf-8') as f:
+                    f.write(output)
+        except Exception as e:
+            with open("logs/xml2abc_error_log.txt", "a", encoding="utf-8") as f:
+                f.write(file + ' ' + str(e) + '\n')
+
+
+if __name__ == '__main__':
+    file_list = []
+    os.makedirs("logs", exist_ok=True)
+
+    # Traverse the specified folder for XML/MXL files
+    for root, dirs, files in os.walk(os.path.abspath(ORI_FOLDER)):
+        for file in files:
+            if file.endswith((".mxl", ".xml", ".musicxml")):
+                filename = os.path.join(root, file).replace("\\", "/")
+                file_list.append(filename)
+
+    # Shuffle and prepare for multiprocessing
+    random.shuffle(file_list)
+    num_files = len(file_list)
+    num_processes = os.cpu_count()
+    file_lists = [file_list[i::num_processes] for i in range(num_processes)]
+
+    # Create a pool for processing
+    with Pool(processes=num_processes) as pool:
+        pool.map(convert_xml2abc, file_lists)

2_data_preprocess.py

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+ORI_FOLDER = ''  # Replace with the path to your folder containing standard ABC notation files
+INTERLEAVED_FOLDER = ''   # Output interleaved ABC notation files to this folder
+AUGMENTED_FOLDER = ''   # Output key-augmented and rest-omitted ABC notation files to this folder
+EVAL_SPLIT = 0.1    # The ratio of eval data 
+
+import os
+import re
+import json
+import shutil
+import random
+from tqdm import tqdm
+from abctoolkit.utils import (
+    remove_information_field, 
+    remove_bar_no_annotations, 
+    Quote_re, 
+    Barlines,
+    extract_metadata_and_parts, 
+    extract_global_and_local_metadata,
+    extract_barline_and_bartext_dict)
+from abctoolkit.convert import unidecode_abc_lines
+from abctoolkit.rotate import rotate_abc
+from abctoolkit.check import check_alignment_unrotated
+from abctoolkit.transpose import Key2index, transpose_an_abc_text
+
+os.makedirs(INTERLEAVED_FOLDER, exist_ok=True)
+os.makedirs(AUGMENTED_FOLDER, exist_ok=True)
+for key in Key2index.keys():
+    key_folder = os.path.join(AUGMENTED_FOLDER, key)
+    os.makedirs(key_folder, exist_ok=True)
+
+
+def abc_preprocess_pipeline(abc_path):
+
+    with open(abc_path, 'r', encoding='utf-8') as f:
+        abc_lines = f.readlines()
+
+    # delete blank lines
+    abc_lines = [line for line in abc_lines if line.strip() != '']
+
+    # unidecode
+    abc_lines = unidecode_abc_lines(abc_lines)
+
+    # clean information field
+    abc_lines = remove_information_field(abc_lines=abc_lines, info_fields=['X:', 'T:', 'C:', 'W:', 'w:', 'Z:', '%%MIDI'])
+
+    # delete bar number annotations
+    abc_lines = remove_bar_no_annotations(abc_lines)
+
+    # delete \"
+    for i, line in enumerate(abc_lines):
+        if re.search(r'^[A-Za-z]:', line) or line.startswith('%'):
+            continue
+        else:
+            if r'\"' in line:
+                abc_lines[i] = abc_lines[i].replace(r'\"', '')
+
+    # delete text annotations with quotes
+    for i, line in enumerate(abc_lines):
+        quote_contents = re.findall(Quote_re, line)
+        for quote_content in quote_contents:
+            for barline in Barlines:
+                if barline in quote_content:
+                    line = line.replace(quote_content, '')
+                    abc_lines[i] = line
+
+    # check bar alignment
+    try:
+        _, bar_no_equal_flag, _ = check_alignment_unrotated(abc_lines)
+        if not bar_no_equal_flag:
+            print(abc_path, 'Unequal bar number')
+            raise Exception
+    except:
+        raise Exception
+
+    # deal with text annotations: remove too long text annotations; remove consecutive non-alphabet/number characters
+    for i, line in enumerate(abc_lines):
+        quote_matches = re.findall(r'"[^"]*"', line)
+        for match in quote_matches:
+            if match == '""':
+                line = line.replace(match, '')
+            if match[1] in ['^', '_']:
+                sub_string = match
+                pattern = r'([^a-zA-Z0-9])\1+'
+                sub_string = re.sub(pattern, r'\1', sub_string)
+                if len(sub_string) <= 40:
+                    line = line.replace(match, sub_string)
+                else:
+                    line = line.replace(match, '')
+        abc_lines[i] = line
+
+    abc_name = os.path.splitext(os.path.split(abc_path)[-1])[0]
+
+    # transpose
+    metadata_lines, part_text_dict = extract_metadata_and_parts(abc_lines)
+    global_metadata_dict, local_metadata_dict = extract_global_and_local_metadata(metadata_lines)
+    if global_metadata_dict['K'][0] == 'none':
+        global_metadata_dict['K'][0] = 'C'
+    ori_key = global_metadata_dict['K'][0]
+
+    interleaved_abc = rotate_abc(abc_lines)
+    interleaved_path = os.path.join(INTERLEAVED_FOLDER, abc_name + '.abc')
+    with open(interleaved_path, 'w') as w:
+        w.writelines(interleaved_abc)
+
+    for key in Key2index.keys():
+        transposed_abc_text = transpose_an_abc_text(abc_lines, key)
+        transposed_abc_lines = transposed_abc_text.split('\n')
+        transposed_abc_lines = list(filter(None, transposed_abc_lines))
+        transposed_abc_lines = [line + '\n' for line in transposed_abc_lines]
+
+        # rest reduction
+        metadata_lines, prefix_dict, left_barline_dict, bar_text_dict, right_barline_dict = \
+            extract_barline_and_bartext_dict(transposed_abc_lines)
+        reduced_abc_lines = metadata_lines
+        for i in range(len(bar_text_dict['V:1'])):
+            line = ''
+            for symbol in prefix_dict.keys():
+                valid_flag = False
+                for char in bar_text_dict[symbol][i]:
+                    if char.isalpha() and not char in ['Z', 'z', 'X', 'x']:
+                        valid_flag = True
+                        break
+                if valid_flag:
+                    if i == 0:
+                        part_patch = '[' + symbol + ']' + prefix_dict[symbol] + left_barline_dict[symbol][0] + bar_text_dict[symbol][0] + right_barline_dict[symbol][0]
+                    else:
+                        part_patch = '[' + symbol + ']' + bar_text_dict[symbol][i] + right_barline_dict[symbol][i]
+                    line += part_patch
+            line += '\n'
+            reduced_abc_lines.append(line)
+            
+            reduced_abc_name = abc_name + '_' + key
+            reduced_abc_path = os.path.join(AUGMENTED_FOLDER, key, reduced_abc_name + '.abc')
+        
+            with open(reduced_abc_path, 'w', encoding='utf-8') as w:
+                w.writelines(reduced_abc_lines)
+
+    return abc_name, ori_key
+
+
+
+
+
+if __name__ == '__main__':
+    
+    data = []
+    file_list = os.listdir(ORI_FOLDER)
+    for file in tqdm(file_list):
+        ori_abc_path = os.path.join(ORI_FOLDER, file)
+        try:
+            abc_name, ori_key = abc_preprocess_pipeline(ori_abc_path)
+        except:
+            print(ori_abc_path, 'failed to pre-process.')
+            continue
+
+        data.append({
+            'path': os.path.join(AUGMENTED_FOLDER, abc_name),
+            'key': ori_key
+        })
+
+    random.shuffle(data)
+    eval_data = data[ : int(EVAL_SPLIT * len(data))]
+    train_data = data[int(EVAL_SPLIT * len(data)) : ]
+
+    data_index_path = AUGMENTED_FOLDER + '.jsonl'
+    eval_index_path = AUGMENTED_FOLDER + '_eval.jsonl'
+    train_index_path = AUGMENTED_FOLDER + '_train.jsonl'
+
+
+    with open(data_index_path, 'w', encoding='utf-8') as w:
+        for d in data:
+            w.write(json.dumps(d) + '\n')
+    with open(eval_index_path, 'w', encoding='utf-8') as w:
+        for d in eval_data:
+            w.write(json.dumps(d) + '\n')
+    with open(train_index_path, 'w', encoding='utf-8') as w:
+        for d in train_data:
+            w.write(json.dumps(d) + '\n')
+
+    
+

3_batch_abc2xml.py

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+ORI_FOLDER = ""  # Replace with the path to your folder containing standard/interleaved abc files
+DES_FOLDER = ""   # The script will convert the abc files and output musicxml files to this folder
+
+import os
+import math
+import random
+import subprocess
+from tqdm import tqdm
+from multiprocessing import Pool
+
+def convert_abc2xml(file_list):
+    cmd = 'python abc2xml.py '
+    for file in tqdm(file_list):
+        filename = file.split('/')[-1]  # Extract file name
+        os.makedirs(DES_FOLDER, exist_ok=True)
+
+        try:
+            p = subprocess.Popen(cmd + '"' + file + '"', stdout=subprocess.PIPE, shell=True)
+            result = p.communicate()
+            output = result[0].decode('utf-8')
+
+            if output == '':
+                with open("logs/abc2xml_error_log.txt", "a", encoding="utf-8") as f:
+                    f.write(file + '\n')
+                continue
+            else:
+                output_path = f"{DES_FOLDER}/" + ".".join(filename.split(".")[:-1]) + ".xml"
+                with open(output_path, 'w', encoding='utf-8') as f:
+                    f.write(output)
+        except Exception as e:
+            with open("logs/abc2xml_error_log.txt", "a", encoding="utf-8") as f:
+                f.write(file + ' ' + str(e) + '\n')
+            pass
+
+if __name__ == '__main__':
+    file_list = []
+    os.makedirs("logs", exist_ok=True)
+
+    # Traverse the specified folder for ABC files
+    for root, dirs, files in os.walk(ORI_FOLDER):
+        for file in files:
+            if not file.endswith(".abc"):
+                continue
+            filename = os.path.join(root, file).replace("\\", "/")
+            file_list.append(filename)
+
+    # Prepare for multiprocessing
+    file_lists = []
+    random.shuffle(file_list)
+    for i in range(os.cpu_count()):
+        start_idx = int(math.floor(i * len(file_list) / os.cpu_count()))
+        end_idx = int(math.floor((i + 1) * len(file_list) / os.cpu_count()))
+        file_lists.append(file_list[start_idx:end_idx])
+
+    pool = Pool(processes=os.cpu_count())
+    pool.map(convert_abc2xml, file_lists)

data.py

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+gt_feature_folder = '../clamp2/feature/schubert_interleaved'
+output_feature_folder = '../clamp2/feature/weights_notagen_schubert-RL2_beta_0.1_lambda_10_p_size_16_p_length_1024_p_layers_20_h_size_1280_lr_1e-06_k_9_p_0.9_temp_1.2'
+output_original_abc_folder = '../output/original/weights_notagen_schubert-RL2_beta_0.1_lambda_10_p_size_16_p_length_1024_p_layers_20_h_size_1280_lr_1e-06_k_9_p_0.9_temp_1.2'
+output_interleaved_abc_folder = '../output/interleaved/weights_notagen_schubert-RL2_beta_0.1_lambda_10_p_size_16_p_length_1024_p_layers_20_h_size_1280_lr_1e-06_k_9_p_0.9_temp_1.2'
+data_index_path = 'schubert_RL3.json'
+data_select_portion = 0.1
+
+import os
+import re
+import json
+import random
+import numpy as np
+from config import *
+from abctoolkit.check import check_alignment_rotated, check_alignment_unrotated
+from abctoolkit.rotate import unrotate_abc
+
+
+def load_npy_files(folder_path_list):
+    """
+    Load all .npy files from a specified folder and return a list of numpy arrays.
+    """
+    npy_list = []
+    for file_path in folder_path_list:
+        if file_path.endswith('.npy'):
+            # file_path = os.path.join(folder_path, file_name)
+            np_array = np.load(file_path)[0]
+            npy_list.append(np_array)
+    return npy_list
+
+def average_npy(npy_list):
+    """
+    Compute the average of a list of numpy arrays.
+    """
+    return np.mean(npy_list, axis=0)
+
+def cosine_similarity(vec1, vec2):
+    """
+    Compute cosine similarity between two numpy arrays.
+    """
+    dot_product = np.dot(vec1, vec2)
+    
+    norm_vec1 = np.linalg.norm(vec1)
+    norm_vec2 = np.linalg.norm(vec2)
+    
+    cosine_sim = dot_product / (norm_vec1 * norm_vec2)
+    
+    return cosine_sim
+
+
+def generate_preference_dict():
+
+    gt_feature_paths = []
+    for gt_feature_file in os.listdir(gt_feature_folder):
+        gt_feature_paths.append(os.path.join(gt_feature_folder, gt_feature_file))
+    gt_features = load_npy_files(gt_feature_paths)
+    gt_avg_feature = average_npy(gt_features)
+
+    output_feature_sim_dict = {}
+    for file in os.listdir(output_feature_folder):
+        output_feature_path = os.path.join(output_feature_folder, file)
+        output_feature = np.load(output_feature_path)[0]
+        sim = cosine_similarity(gt_avg_feature, output_feature)
+        output_feature_sim_dict[file[:-4]] = sim
+
+    threshold = int(len(output_feature_sim_dict) * data_select_portion)
+    sorted_output_files = sorted(output_feature_sim_dict.keys(), key=lambda item: output_feature_sim_dict[item], reverse=True)
+    
+    chosen_index = 0
+    i = 0
+    chosen_abc_paths = []
+    while chosen_index < threshold and i < len(sorted_output_files):
+
+        chosen_flag = True
+
+        file = sorted_output_files[i]
+        output_interleaved_abc_path = os.path.join(output_interleaved_abc_folder, file + '.abc')
+
+        with open(output_interleaved_abc_path, 'r') as f:
+            abc_lines = f.readlines()
+
+        # check aligment
+        try:
+            abc_lines_unrotated = unrotate_abc(abc_lines)
+            barline_equal_flag, bar_no_equal_flag, bar_dur_equal_flag = check_alignment_unrotated(abc_lines_unrotated)
+            if not (barline_equal_flag and bar_no_equal_flag and bar_dur_equal_flag):
+                raise Exception
+        except:
+            chosen_flag = False
+
+        # check header: sheets where staves for the same instrument are not grouped together are excluded from the chosen set.
+        appeared_inst = set()
+        last_inst = ''
+        for line in abc_lines:
+            if line.startswith('V:') and 'nm=' in line:
+                match = re.search(r'nm="([^"]+)"', line)
+                if match:
+                    inst = match.group(1)
+                    if inst != last_inst and inst in appeared_inst:
+                        chosen_flag = False
+                        break
+                    else:
+                        last_inst = inst
+                        appeared_inst.add(inst)                           
+
+        # check plagiarism: sheets with sim > 0.95 are excluded
+        output_feature_path = os.path.join(output_feature_folder, file + '.npy')
+        output_feature = np.load(output_feature_path)[0]
+        for gt_feature_file in os.listdir(gt_feature_folder):
+            gt_feature_path = os.path.join(gt_feature_folder, gt_feature_file)
+            gt_feature = np.load(gt_feature_path)[0]
+            sim = cosine_similarity(output_feature, gt_feature)
+            if sim > 0.95:
+                chosen_flag = False
+                break
+
+        if chosen_flag:
+            original_abc_path = os.path.join(output_original_abc_folder, file + '.abc')
+            chosen_abc_paths.append(original_abc_path)
+            chosen_index += 1
+        else:
+            print(file, 'skipped')
+
+        i += 1
+
+    rejected_abc_paths = [os.path.join(output_original_abc_folder, file + '.abc') for file in sorted_output_files[-threshold:]]
+    preference_dict = {'chosen': chosen_abc_paths, 'rejected': rejected_abc_paths}
+
+    with open(data_index_path, 'w') as w:
+        json.dump(preference_dict, w, indent=4)
+
+
+if __name__ == '__main__':
+
+    generate_preference_dict()
+
+    

train-gen (1).py

@@ -0,0 +1,325 @@
+import os
+import gc
+import time
+import math
+import json
+import wandb
+import torch
+import random
+import numpy as np
+from utils import *
+from config import *
+from tqdm import tqdm
+from copy import deepcopy
+from torch.cuda.amp import autocast, GradScaler
+from torch.utils.data import Dataset, DataLoader
+from transformers import GPT2Config, LlamaConfig, get_scheduler, get_constant_schedule_with_warmup
+import torch.distributed as dist
+from torch.nn.parallel import DistributedDataParallel as DDP
+from torch.utils.data.distributed import DistributedSampler
+
+# Set up distributed training
+world_size = int(os.environ['WORLD_SIZE']) if 'WORLD_SIZE' in os.environ else 1
+global_rank = int(os.environ['RANK']) if 'RANK' in os.environ else 0
+local_rank = int(os.environ['LOCAL_RANK']) if 'LOCAL_RANK' in os.environ else 0
+
+if world_size > 1:
+    torch.cuda.set_device(local_rank)
+    device = torch.device("cuda", local_rank)
+    dist.init_process_group(backend='nccl') if world_size > 1 else None
+else:
+    device = torch.device("cuda") if torch.cuda.is_available() else torch.device("cpu")
+    
+# Set random seed
+seed = 0 + global_rank
+random.seed(seed)
+np.random.seed(seed)
+torch.manual_seed(seed)
+torch.cuda.manual_seed_all(seed)
+torch.backends.cudnn.deterministic = True
+torch.backends.cudnn.benchmark = False
+
+batch_size = BATCH_SIZE
+
+patchilizer = Patchilizer()
+
+patch_config = GPT2Config(num_hidden_layers=PATCH_NUM_LAYERS, 
+                    max_length=PATCH_LENGTH, 
+                    max_position_embeddings=PATCH_LENGTH,
+                    n_embd=HIDDEN_SIZE,
+                    num_attention_heads=HIDDEN_SIZE//64,
+                    vocab_size=1)
+char_config = GPT2Config(num_hidden_layers=CHAR_NUM_LAYERS, 
+                            max_length=PATCH_SIZE+1, 
+                            max_position_embeddings=PATCH_SIZE+1,
+                            hidden_size=HIDDEN_SIZE,
+                            num_attention_heads=HIDDEN_SIZE//64,
+                            vocab_size=128)
+
+model = NotaGenLMHeadModel(encoder_config=patch_config, decoder_config=char_config)
+
+model = model.to(device)
+
+# print parameter number
+print("Parameter Number: "+str(sum(p.numel() for p in model.parameters() if p.requires_grad)))
+
+if world_size > 1:
+    model = DDP(model, device_ids=[local_rank], output_device=local_rank,  find_unused_parameters=True)
+
+scaler = GradScaler()
+is_autocast = True
+optimizer = torch.optim.AdamW(model.parameters(), lr=LEARNING_RATE)
+
+
+def clear_unused_tensors():
+    gc.disable()  # Temporarily disable garbage collection
+    try:
+        # Get the set of tensor ids used by the model
+        if hasattr(model, "module"):
+            model_tensors = {id(p) for p in model.module.parameters()}
+        else:
+            model_tensors = {id(p) for p in model.parameters()}
+        
+        # Get the set of tensor ids used by the optimizer
+        optimizer_tensors = {
+            id(state) 
+            for state_dict in optimizer.state.values() 
+            for state in state_dict.values()
+            if isinstance(state, torch.Tensor)  # Ensure only tensors are considered
+        }
+
+        # List of all CUDA tensors currently in memory
+        tensors = [obj for obj in gc.get_objects() if isinstance(obj, torch.Tensor) and obj.is_cuda]
+        
+        # Create weak references to avoid interfering with garbage collection
+        tensor_refs = [weakref.ref(tensor) for tensor in tensors]
+
+        for tensor_ref in tensor_refs:
+            tensor = tensor_ref()  # Dereference the weak reference
+            if tensor is not None and id(tensor) not in model_tensors and id(tensor) not in optimizer_tensors:
+                # Mark the tensor for deletion
+                tensor.detach_()  # Detach from computation graph
+                del tensor  # Delete the tensor reference
+    except:
+        pass
+
+    finally:
+        gc.enable()  # Re-enable garbage collection
+        gc.collect()  # Force a garbage collection
+        torch.cuda.empty_cache()  # Clear the CUDA cache
+
+def collate_batch(input_batches):
+    
+    input_patches, input_masks = zip(*input_batches)
+    input_patches = torch.nn.utils.rnn.pad_sequence(input_patches, batch_first=True, padding_value=0)
+    input_masks = torch.nn.utils.rnn.pad_sequence(input_masks, batch_first=True, padding_value=0)
+
+    return input_patches.to(device), input_masks.to(device)
+
+def split_into_minibatches(input_patches, input_masks, minibatch_size):
+    minibatches = []
+    for start_idx in range(0, len(input_patches), minibatch_size):
+        end_idx = start_idx + minibatch_size
+        minibatch_patches = input_patches[start_idx:end_idx]
+        minibatch_masks = input_masks[start_idx:end_idx]
+        minibatches.append((minibatch_patches, minibatch_masks))
+    return minibatches
+
+class NotaGenDataset(Dataset):
+    def __init__(self, filenames):
+        self.filenames = filenames
+
+    def __len__(self):
+        return len(self.filenames)
+
+    def __getitem__(self, idx):
+
+        filepath = self.filenames[idx]['path']
+
+        key = random.choice(['C#', 'F#', 'B', 'E', 'A', 'D', 'G', 'C', 'F', 'Bb', 'Eb', 'Ab', 'Db', 'Gb', 'Cb'])
+
+        folder = os.path.dirname(filepath)
+        name = os.path.split(filepath)[-1]
+        des_filepath = os.path.join(folder, key, name + '_' + key + '.abc')
+        
+        with open(des_filepath, 'r', encoding='utf-8') as f:
+            abc_text = f.read()
+        
+        file_bytes = patchilizer.encode_train(abc_text)
+        file_masks = [1] * len(file_bytes)
+
+        file_bytes = torch.tensor(file_bytes, dtype=torch.long)
+        file_masks = torch.tensor(file_masks, dtype=torch.long)
+        
+        return file_bytes, file_masks
+
+def process_one_batch(batch):
+    input_patches, input_masks = batch
+    loss = model(input_patches, input_masks).loss
+
+    # Reduce the loss on GPU 0
+    if world_size > 1:
+        loss = loss.unsqueeze(0)
+        dist.reduce(loss, dst=0)
+        loss = loss / world_size
+        dist.broadcast(loss, src=0)
+
+    return loss
+
+
+# do one epoch for training
+def train_epoch(epoch):
+    tqdm_train_set = tqdm(train_set)
+    total_train_loss = 0
+    iter_idx = 1
+    model.train()
+    train_steps = (epoch-1)*len(train_set)
+
+    for batch in tqdm_train_set:
+        minibatches = split_into_minibatches(batch[0], batch[1], BATCH_SIZE//ACCUMULATION_STEPS)
+        for minibatch in minibatches:
+            with autocast():
+                loss = process_one_batch(minibatch) / ACCUMULATION_STEPS
+            scaler.scale(loss).backward()
+            total_train_loss += loss.item()
+        scaler.step(optimizer)
+        scaler.update()
+        
+        lr_scheduler.step()
+        model.zero_grad(set_to_none=True)
+        tqdm_train_set.set_postfix({str(global_rank)+'_train_loss': total_train_loss / iter_idx})
+        train_steps += 1
+
+        # Log the training loss to wandb
+        if global_rank==0 and WANDB_LOGGING:
+            wandb.log({"train_loss": total_train_loss / iter_idx}, step=train_steps)
+
+        iter_idx += 1
+        if iter_idx % 1000 == 0:
+            clear_unused_tensors()
+        
+    return total_train_loss / (iter_idx-1)
+
+# do one epoch for eval
+def eval_epoch():
+    tqdm_eval_set = tqdm(eval_set)
+    total_eval_loss = 0
+    total_eval_bpb = 0
+    iter_idx = 1
+    model.eval()
+  
+    # Evaluate data for one epoch
+    for batch in tqdm_eval_set: 
+        minibatches = split_into_minibatches(batch[0], batch[1], BATCH_SIZE//ACCUMULATION_STEPS)
+        for minibatch in minibatches:
+            with torch.no_grad():
+                loss = process_one_batch(minibatch) / ACCUMULATION_STEPS
+            total_eval_loss += loss.item()
+        tqdm_eval_set.set_postfix({str(global_rank)+'_eval_loss': total_eval_loss / iter_idx})
+        iter_idx += 1
+    return total_eval_loss / (iter_idx-1)
+
+# train and eval
+if __name__ == "__main__":
+    
+    # Initialize wandb
+    if WANDB_LOGGING and global_rank==0:
+        wandb.login(key=WANDB_KEY)
+        wandb.init(project="notagen",
+                   name=WANDB_NAME)
+    
+    # load data
+    with open(DATA_TRAIN_INDEX_PATH, "r", encoding="utf-8") as f:
+        print("Loading Data...")
+        train_files = []
+        for line in f:
+            train_files.append(json.loads(line))
+    
+    with open(DATA_EVAL_INDEX_PATH, "r", encoding="utf-8") as f:
+        print("Loading Data...")
+        eval_files = []
+        for line in f:
+            eval_files.append(json.loads(line))
+       
+    train_batch_nums = int(len(train_files) / batch_size)
+    eval_batch_nums = int(len(eval_files) / batch_size)
+
+
+    random.shuffle(train_files)
+    random.shuffle(eval_files)
+
+    train_files = train_files[:train_batch_nums*batch_size]
+    eval_files = eval_files[:eval_batch_nums*batch_size]
+
+    train_set = NotaGenDataset(train_files)
+    eval_set = NotaGenDataset(eval_files)
+
+    train_sampler = DistributedSampler(train_set, num_replicas=world_size, rank=local_rank)
+    eval_sampler = DistributedSampler(eval_set, num_replicas=world_size, rank=local_rank)
+
+    train_set = DataLoader(train_set, batch_size=batch_size, collate_fn=collate_batch, sampler=train_sampler, shuffle = (train_sampler is None))
+    eval_set = DataLoader(eval_set, batch_size=batch_size, collate_fn=collate_batch, sampler=eval_sampler, shuffle = (train_sampler is None))
+
+    lr_scheduler = get_constant_schedule_with_warmup(optimizer=optimizer, num_warmup_steps=1000)
+
+    model = model.to(device)
+    optimizer = torch.optim.AdamW(model.parameters(), lr=LEARNING_RATE)
+
+    if LOAD_FROM_CHECKPOINT and os.path.exists(WEIGHTS_PATH):
+        # Load checkpoint to CPU
+        checkpoint = torch.load(WEIGHTS_PATH, map_location='cpu')
+
+        # Here, model is assumed to be on GPU
+        # Load state dict to CPU model first, then move the model to GPU
+        if torch.cuda.device_count() > 1:
+            # If you have a DataParallel model, you need to load to model.module instead
+            cpu_model = deepcopy(model.module)
+            cpu_model.load_state_dict(checkpoint['model'])
+            model.module.load_state_dict(cpu_model.state_dict())
+        else:
+            # Load to a CPU clone of the model, then load back
+            cpu_model = deepcopy(model)
+            cpu_model.load_state_dict(checkpoint['model'])
+            model.load_state_dict(cpu_model.state_dict())
+        optimizer.load_state_dict(checkpoint['optimizer'])
+        lr_scheduler.load_state_dict(checkpoint['lr_sched'])
+        pre_epoch = checkpoint['epoch']
+        best_epoch = checkpoint['best_epoch']
+        min_eval_loss = checkpoint['min_eval_loss']
+        print("Successfully Loaded Checkpoint from Epoch %d" % pre_epoch)
+        checkpoint = None
+    
+    else:
+        pre_epoch = 0
+        best_epoch = 0
+        min_eval_loss = 100
+
+    for epoch in range(1+pre_epoch, NUM_EPOCHS+1):
+        train_sampler.set_epoch(epoch)
+        eval_sampler.set_epoch(epoch)
+        print('-' * 21 + "Epoch " + str(epoch) + '-' * 21)
+        train_loss = train_epoch(epoch)
+        eval_loss = eval_epoch()
+        if global_rank==0:
+            with open(LOGS_PATH,'a') as f:
+                f.write("Epoch " + str(epoch) + "\ntrain_loss: " + str(train_loss) + "\neval_loss: " +str(eval_loss) + "\ntime: " + time.asctime(time.localtime(time.time())) + "\n\n")
+            if eval_loss < min_eval_loss:
+                best_epoch = epoch
+                min_eval_loss = eval_loss
+                checkpoint = { 
+                                'model': model.module.state_dict() if hasattr(model, "module") else model.state_dict(),
+                                'optimizer': optimizer.state_dict(),
+                                'lr_sched': lr_scheduler.state_dict(),
+                                'epoch': epoch,
+                                'best_epoch': best_epoch,
+                                'min_eval_loss': min_eval_loss
+                                }
+                torch.save(checkpoint, WEIGHTS_PATH)
+        
+        if world_size > 1:
+            dist.barrier()
+
+    if global_rank==0:
+        print("Best Eval Epoch : "+str(best_epoch))
+        print("Min Eval Loss : "+str(min_eval_loss))
+

train-gen.py

@@ -0,0 +1,374 @@
+import os
+import gc
+import time
+import math
+import json
+import wandb
+import torch
+import random
+import numpy as np
+from abctoolkit.transpose import Key2index, Key2Mode
+from utils import *
+from config import *
+from tqdm import tqdm
+from copy import deepcopy
+from torch.cuda.amp import autocast, GradScaler
+from torch.utils.data import Dataset, DataLoader
+from transformers import GPT2Config, LlamaConfig, get_scheduler, get_constant_schedule_with_warmup
+import torch.distributed as dist
+from torch.nn.parallel import DistributedDataParallel as DDP
+from torch.utils.data.distributed import DistributedSampler
+
+Index2Key = {index: key for key, index in Key2index.items() if index not in [1, 11]}
+Mode2Key = {mode: key for key, mode_list in Key2Mode.items() for mode in mode_list }
+
+# Set up distributed training
+world_size = int(os.environ['WORLD_SIZE']) if 'WORLD_SIZE' in os.environ else 1
+global_rank = int(os.environ['RANK']) if 'RANK' in os.environ else 0
+local_rank = int(os.environ['LOCAL_RANK']) if 'LOCAL_RANK' in os.environ else 0
+
+if world_size > 1:
+    torch.cuda.set_device(local_rank)
+    device = torch.device("cuda", local_rank)
+    dist.init_process_group(backend='nccl') if world_size > 1 else None
+else:
+    device = torch.device("cuda") if torch.cuda.is_available() else torch.device("cpu")
+    
+# Set random seed
+seed = 0 + global_rank
+random.seed(seed)
+np.random.seed(seed)
+torch.manual_seed(seed)
+torch.cuda.manual_seed_all(seed)
+torch.backends.cudnn.deterministic = True
+torch.backends.cudnn.benchmark = False
+
+batch_size = BATCH_SIZE
+
+patchilizer = Patchilizer()
+
+patch_config = GPT2Config(num_hidden_layers=PATCH_NUM_LAYERS, 
+                    max_length=PATCH_LENGTH, 
+                    max_position_embeddings=PATCH_LENGTH,
+                    n_embd=HIDDEN_SIZE,
+                    num_attention_heads=HIDDEN_SIZE//64,
+                    vocab_size=1)
+char_config = GPT2Config(num_hidden_layers=CHAR_NUM_LAYERS, 
+                            max_length=PATCH_SIZE+1, 
+                            max_position_embeddings=PATCH_SIZE+1,
+                            hidden_size=HIDDEN_SIZE,
+                            num_attention_heads=HIDDEN_SIZE//64,
+                            vocab_size=128)
+
+model = NotaGenLMHeadModel(encoder_config=patch_config, decoder_config=char_config)
+
+model = model.to(device)
+
+# print parameter number
+print("Parameter Number: "+str(sum(p.numel() for p in model.parameters() if p.requires_grad)))
+
+if world_size > 1:
+    model = DDP(model, device_ids=[local_rank], output_device=local_rank,  find_unused_parameters=True)
+
+scaler = GradScaler()
+is_autocast = True
+optimizer = torch.optim.AdamW(model.parameters(), lr=LEARNING_RATE)
+
+
+def clear_unused_tensors():
+    gc.disable()  # Temporarily disable garbage collection
+    try:
+        # Get the set of tensor ids used by the model
+        if hasattr(model, "module"):
+            model_tensors = {id(p) for p in model.module.parameters()}
+        else:
+            model_tensors = {id(p) for p in model.parameters()}
+        
+        # Get the set of tensor ids used by the optimizer
+        optimizer_tensors = {
+            id(state) 
+            for state_dict in optimizer.state.values() 
+            for state in state_dict.values()
+            if isinstance(state, torch.Tensor)  # Ensure only tensors are considered
+        }
+
+        # List of all CUDA tensors currently in memory
+        tensors = [obj for obj in gc.get_objects() if isinstance(obj, torch.Tensor) and obj.is_cuda]
+        
+        # Create weak references to avoid interfering with garbage collection
+        tensor_refs = [weakref.ref(tensor) for tensor in tensors]
+
+        for tensor_ref in tensor_refs:
+            tensor = tensor_ref()  # Dereference the weak reference
+            if tensor is not None and id(tensor) not in model_tensors and id(tensor) not in optimizer_tensors:
+                # Mark the tensor for deletion
+                tensor.detach_()  # Detach from computation graph
+                del tensor  # Delete the tensor reference
+    except:
+        pass
+
+    finally:
+        gc.enable()  # Re-enable garbage collection
+        gc.collect()  # Force a garbage collection
+        torch.cuda.empty_cache()  # Clear the CUDA cache
+
+def collate_batch(input_batches):
+    
+    input_patches, input_masks = zip(*input_batches)
+    input_patches = torch.nn.utils.rnn.pad_sequence(input_patches, batch_first=True, padding_value=0)
+    input_masks = torch.nn.utils.rnn.pad_sequence(input_masks, batch_first=True, padding_value=0)
+
+    return input_patches.to(device), input_masks.to(device)
+
+def split_into_minibatches(input_patches, input_masks, minibatch_size):
+    minibatches = []
+    for start_idx in range(0, len(input_patches), minibatch_size):
+        end_idx = start_idx + minibatch_size
+        minibatch_patches = input_patches[start_idx:end_idx]
+        minibatch_masks = input_masks[start_idx:end_idx]
+        minibatches.append((minibatch_patches, minibatch_masks))
+    return minibatches
+
+class NotaGenDataset(Dataset):
+    def __init__(self, filenames):
+        self.filenames = filenames
+
+    def __len__(self):
+        return len(self.filenames)
+
+    def __getitem__(self, idx):
+
+        filepath = self.filenames[idx]['path']
+        ori_key = Mode2Key[self.filenames[idx]['key']]
+
+        # choose a key to transpose, according to a probility distribution
+        ori_key_index = Key2index[ori_key]
+        available_index = [(ori_key_index + offset) % 12 for offset in range(-3, 4)]
+        index_prob = [1/16, 2/16, 3/16, 4/16, 3/16, 2/16, 1/16]
+        index_prob_range = [0] + [sum(index_prob[0 : i + 1]) for i in range(len(index_prob))]
+        random_number = random.random()
+        for i in range(len(index_prob_range) - 1):
+            if index_prob_range[i] <= random_number < index_prob_range[i + 1]:
+                des_key_index = available_index[i]
+        if des_key_index == 1:
+            des_key = 'Db' if random.random() < 0.8 else 'C#'   
+        elif des_key_index == 11:
+            des_key = 'B' if random.random() < 0.8 else 'Cb'
+        elif des_key_index == 6:
+            des_key = 'F#' if random.random() < 0.5 else 'Gb'
+        else:
+            des_key = Index2Key[des_key_index]
+
+        folder = os.path.dirname(filepath)
+        name = os.path.split(filepath)[-1]
+        des_filepath = os.path.join(folder, des_key, name + '_' + des_key + '.abc')
+        
+        with open(des_filepath, 'r', encoding='utf-8') as f:
+            abc_text = f.read()
+
+        file_bytes = patchilizer.encode_train(abc_text)
+        file_masks = [1] * len(file_bytes)
+
+        file_bytes = torch.tensor(file_bytes, dtype=torch.long)
+        file_masks = torch.tensor(file_masks, dtype=torch.long)
+        
+        return file_bytes, file_masks
+
+
+def process_one_batch(batch):
+    input_patches, input_masks = batch
+    loss = model(input_patches, input_masks).loss
+
+    # Reduce the loss on GPU 0
+    if world_size > 1:
+        loss = loss.unsqueeze(0)
+        dist.reduce(loss, dst=0)
+        loss = loss / world_size
+        dist.broadcast(loss, src=0)
+
+    return loss
+
+
+# do one epoch for training
+def train_epoch(epoch):
+    tqdm_train_set = tqdm(train_set)
+    total_train_loss = 0
+    iter_idx = 1
+    model.train()
+    train_steps = (epoch-1)*len(train_set)
+
+    for batch in tqdm_train_set:
+        minibatches = split_into_minibatches(batch[0], batch[1], BATCH_SIZE//ACCUMULATION_STEPS)
+        for minibatch in minibatches:
+            with autocast():
+                loss = process_one_batch(minibatch) / ACCUMULATION_STEPS
+            scaler.scale(loss).backward()
+            total_train_loss += loss.item()
+        scaler.step(optimizer)
+        scaler.update()
+        
+        lr_scheduler.step()
+        model.zero_grad(set_to_none=True)
+        tqdm_train_set.set_postfix({str(global_rank)+'_train_loss': total_train_loss / iter_idx})
+        train_steps += 1
+
+        # Log the training loss to wandb
+        if global_rank==0 and WANDB_LOGGING:
+            wandb.log({"train_loss": total_train_loss / iter_idx}, step=train_steps)
+
+        iter_idx += 1
+        if iter_idx % 1000 == 0:
+            clear_unused_tensors()
+        
+    return total_train_loss / (iter_idx-1)
+
+# do one epoch for eval
+def eval_epoch():
+    tqdm_eval_set = tqdm(eval_set)
+    total_eval_loss = 0
+    total_eval_bpb = 0
+    iter_idx = 1
+    model.eval()
+  
+    # Evaluate data for one epoch
+    for batch in tqdm_eval_set: 
+        minibatches = split_into_minibatches(batch[0], batch[1], BATCH_SIZE//ACCUMULATION_STEPS)
+        for minibatch in minibatches:
+            with torch.no_grad():
+                loss = process_one_batch(minibatch) / ACCUMULATION_STEPS
+            total_eval_loss += loss.item()
+        tqdm_eval_set.set_postfix({str(global_rank)+'_eval_loss': total_eval_loss / iter_idx})
+        iter_idx += 1
+    return total_eval_loss / (iter_idx-1)
+
+# train and eval
+if __name__ == "__main__":
+    
+    # Initialize wandb
+    if WANDB_LOGGING and global_rank==0:
+        wandb.login(key=WANDB_KEY)
+        wandb.init(project="notagen",
+                   name=WANDB_NAME)
+    
+    # load data
+    with open(DATA_TRAIN_INDEX_PATH, "r", encoding="utf-8") as f:
+        print("Loading Data...")
+        train_files = []
+        for line in f:
+            train_files.append(json.loads(line))
+    
+    with open(DATA_EVAL_INDEX_PATH, "r", encoding="utf-8") as f:
+        print("Loading Data...")
+        eval_files = []
+        for line in f:
+            eval_files.append(json.loads(line))
+
+    if len(eval_files) == 0:
+        train_files, eval_files = split_data(train_files)
+       
+    train_batch_nums = int(len(train_files) / batch_size)
+    eval_batch_nums = int(len(eval_files) / batch_size)
+
+    random.shuffle(train_files)
+    random.shuffle(eval_files)
+
+    train_files = train_files[:train_batch_nums*batch_size]
+    eval_files = eval_files[:eval_batch_nums*batch_size]
+
+    train_set = NotaGenDataset(train_files)
+    eval_set = NotaGenDataset(eval_files)
+
+    train_sampler = DistributedSampler(train_set, num_replicas=world_size, rank=local_rank)
+    eval_sampler = DistributedSampler(eval_set, num_replicas=world_size, rank=local_rank)
+
+    train_set = DataLoader(train_set, batch_size=batch_size, collate_fn=collate_batch, sampler=train_sampler, shuffle = (train_sampler is None))
+    eval_set = DataLoader(eval_set, batch_size=batch_size, collate_fn=collate_batch, sampler=eval_sampler, shuffle = (train_sampler is None))
+
+    lr_scheduler = get_constant_schedule_with_warmup(optimizer=optimizer, num_warmup_steps=1000)
+
+    model = model.to(device)
+    optimizer = torch.optim.AdamW(model.parameters(), lr=LEARNING_RATE)
+
+    if not LOAD_FROM_CHECKPOINT:
+        if os.path.exists(PRETRAINED_PATH):
+            # Load pre-trained checkpoint to CPU
+            checkpoint = torch.load(PRETRAINED_PATH, map_location='cpu')
+    
+            # Here, model is assumed to be on GPU
+            # Load state dict to CPU model first, then move the model to GPU
+            if torch.cuda.device_count() > 1:
+                # If you have a DataParallel model, you need to load to model.module instead
+                cpu_model = deepcopy(model.module)
+                cpu_model.load_state_dict(checkpoint['model'])
+                model.module.load_state_dict(cpu_model.state_dict())
+            else:
+                # Load to a CPU clone of the model, then load back
+                cpu_model = deepcopy(model)
+                cpu_model.load_state_dict(checkpoint['model'])
+                model.load_state_dict(cpu_model.state_dict())
+                
+            print(f"Successfully Loaded Pretrained Checkpoint at Epoch {checkpoint['epoch']} with Loss {checkpoint['min_eval_loss']}")
+
+            pre_epoch = 0
+            best_epoch = 0
+            min_eval_loss = 100
+        else:
+            raise Exception('Pre-trained Checkpoint not found. Please check your pre-trained ckpt path.')
+            
+    else:
+        if os.path.exists(WEIGHTS_PATH):
+            # Load checkpoint to CPU
+            checkpoint = torch.load(WEIGHTS_PATH, map_location='cpu')
+    
+            # Here, model is assumed to be on GPU
+            # Load state dict to CPU model first, then move the model to GPU
+            if torch.cuda.device_count() > 1:
+                # If you have a DataParallel model, you need to load to model.module instead
+                cpu_model = deepcopy(model.module)
+                cpu_model.load_state_dict(checkpoint['model'])
+                model.module.load_state_dict(cpu_model.state_dict())
+            else:
+                # Load to a CPU clone of the model, then load back
+                cpu_model = deepcopy(model)
+                cpu_model.load_state_dict(checkpoint['model'])
+                model.load_state_dict(cpu_model.state_dict())
+            optimizer.load_state_dict(checkpoint['optimizer'])
+            lr_scheduler.load_state_dict(checkpoint['lr_sched'])
+            pre_epoch = checkpoint['epoch']
+            best_epoch = checkpoint['best_epoch']
+            min_eval_loss = checkpoint['min_eval_loss']
+            print("Successfully Loaded Checkpoint from Epoch %d" % pre_epoch)
+            checkpoint = None
+
+        else:
+            raise Exception('Checkpoint not found to continue training. Please check your parameter settings.')
+    
+
+    for epoch in range(1+pre_epoch, NUM_EPOCHS+1):
+        train_sampler.set_epoch(epoch)
+        eval_sampler.set_epoch(epoch)
+        print('-' * 21 + "Epoch " + str(epoch) + '-' * 21)
+        train_loss = train_epoch(epoch)
+        eval_loss = eval_epoch()
+        if global_rank==0:
+            with open(LOGS_PATH,'a') as f:
+                f.write("Epoch " + str(epoch) + "\ntrain_loss: " + str(train_loss) + "\neval_loss: " +str(eval_loss) + "\ntime: " + time.asctime(time.localtime(time.time())) + "\n\n")
+            if eval_loss < min_eval_loss:
+                best_epoch = epoch
+                min_eval_loss = eval_loss
+                checkpoint = { 
+                                'model': model.module.state_dict() if hasattr(model, "module") else model.state_dict(),
+                                'optimizer': optimizer.state_dict(),
+                                'lr_sched': lr_scheduler.state_dict(),
+                                'epoch': epoch,
+                                'best_epoch': best_epoch,
+                                'min_eval_loss': min_eval_loss
+                                }
+                torch.save(checkpoint, WEIGHTS_PATH)
+        
+        if world_size > 1:
+            dist.barrier()
+
+    if global_rank==0:
+        print("Best Eval Epoch : "+str(best_epoch))
+        print("Min Eval Loss : "+str(min_eval_loss))

xml2abc.py

@@ -0,0 +1,1609 @@
+#!/usr/bin/env python
+# coding=latin-1
+'''
+Copyright (C) 2012-2018: W.G. Vree
+Contributions: M. Tarenskeen, N. Liberg, Paul Villiger, Janus Meuris, Larry Myerscough, 
+Dick Jackson, Jan Wybren de Jong, Mark Zealey.
+
+This program is free software; you can redistribute it and/or modify it under the terms of the
+Lesser GNU General Public License as published by the Free Software Foundation;
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+See the Lesser GNU General Public License for more details. <http://www.gnu.org/licenses/lgpl.html>.
+'''
+
+'''Small revisions made for NotaGen to improve the succuess rate of conversion.'''
+
+try:    import xml.etree.cElementTree as E
+except: import xml.etree.ElementTree as E
+import os, sys, types, re, math
+
+VERSION = 143
+
+python3 = sys.version_info.major > 2
+if python3:
+    tupletype = tuple
+    listtype = list
+    max_int = sys.maxsize
+else:
+    tupletype = types.TupleType
+    listtype = types.ListType
+    max_int = sys.maxint
+
+note_ornamentation_map = {        # for notations/, modified from EasyABC
+    'ornaments/trill-mark':       'T',
+    'ornaments/mordent':          'M',
+    'ornaments/inverted-mordent': 'P',
+    'ornaments/turn':             '!turn!',
+    'ornaments/inverted-turn':    '!invertedturn!',
+    'technical/up-bow':           'u',
+    'technical/down-bow':         'v',
+    'technical/harmonic':         '!open!',
+    'technical/open-string':      '!open!',
+    'technical/stopped':          '!plus!',
+    'technical/snap-pizzicato':   '!snap!',
+    'technical/thumb-position':   '!thumb!',
+    'articulations/accent':       '!>!',
+    'articulations/strong-accent':'!^!',
+    'articulations/staccato':     '.',
+    'articulations/staccatissimo':'!wedge!',
+    'articulations/scoop':        '!slide!',
+    'fermata':                    '!fermata!',
+    'arpeggiate':                 '!arpeggio!',
+    'articulations/tenuto':       '!tenuto!',
+    'articulations/staccatissimo':'!wedge!', # not sure whether this is the right translation
+    'articulations/spiccato':     '!wedge!', # not sure whether this is the right translation
+    'articulations/breath-mark':  '!breath!', # this may need to be tested to make sure it appears on the right side of the note
+    'articulations/detached-legato': '!tenuto!.',
+}
+
+dynamics_map = {    # for direction/direction-type/dynamics/
+    'p':    '!p!',
+    'pp':   '!pp!',
+    'ppp':  '!ppp!',
+    'pppp': '!pppp!',
+    'f':    '!f!',
+    'ff':   '!ff!',
+    'fff':  '!fff!',
+    'ffff': '!ffff!',
+    'mp':   '!mp!',
+    'mf':   '!mf!',
+    'sfz':  '!sfz!',
+}
+
+percSvg = '''%%beginsvg
+    <defs>
+    <text id="x" x="-3" y="0">&#xe263;</text>
+    <text id="x-" x="-3" y="0">&#xe263;</text>
+    <text id="x+" x="-3" y="0">&#xe263;</text>
+    <text id="normal" x="-3.7" y="0">&#xe0a3;</text>
+    <text id="normal-" x="-3.7" y="0">&#xe0a3;</text>
+    <text id="normal+" x="-3.7" y="0">&#xe0a4;</text>
+    <g id="circle-x"><text x="-3" y="0">&#xe263;</text><circle r="4" class="stroke"></circle></g>
+    <g id="circle-x-"><text x="-3" y="0">&#xe263;</text><circle r="4" class="stroke"></circle></g>
+    <path id="triangle" d="m-4 -3.2l4 6.4 4 -6.4z" class="stroke" style="stroke-width:1.4"></path>
+    <path id="triangle-" d="m-4 -3.2l4 6.4 4 -6.4z" class="stroke" style="stroke-width:1.4"></path>
+    <path id="triangle+" d="m-4 -3.2l4 6.4 4 -6.4z" class="stroke" style="fill:#000"></path>
+    <path id="square" d="m-3.5 3l0 -6.2 7.2 0 0 6.2z" class="stroke" style="stroke-width:1.4"></path>
+    <path id="square-" d="m-3.5 3l0 -6.2 7.2 0 0 6.2z" class="stroke" style="stroke-width:1.4"></path>
+    <path id="square+" d="m-3.5 3l0 -6.2 7.2 0 0 6.2z" class="stroke" style="fill:#000"></path>
+    <path id="diamond" d="m0 -3l4.2 3.2 -4.2 3.2 -4.2 -3.2z" class="stroke" style="stroke-width:1.4"></path>
+    <path id="diamond-" d="m0 -3l4.2 3.2 -4.2 3.2 -4.2 -3.2z" class="stroke" style="stroke-width:1.4"></path>
+    <path id="diamond+" d="m0 -3l4.2 3.2 -4.2 3.2 -4.2 -3.2z" class="stroke" style="fill:#000"></path>
+    </defs>
+    %%endsvg'''
+
+tabSvg = '''%%beginsvg
+    <style type="text/css">
+    .bf {font-family:sans-serif; font-size:7px}
+    </style>
+    <defs>
+    <rect id="clr" x="-3" y="-1" width="6" height="5" fill="white"></rect>
+    <rect id="clr2" x="-3" y="-1" width="11" height="5" fill="white"></rect>'''
+
+kopSvg = '<g id="kop%s" class="bf"><use xlink:href="#clr"></use><text x="-2" y="3">%s</text></g>\n'
+kopSvg2 = '<g id="kop%s" class="bf"><use xlink:href="#clr2"></use><text x="-2" y="3">%s</text></g>\n'
+
+def info (s, warn=1): sys.stderr.write ((warn and '-- ' or '') + s + '\n')
+
+#-------------------
+# data abstractions
+#-------------------
+class Measure:
+    def __init__ (s, p):
+        s.reset ()
+        s.ixp = p       # part number  
+        s.ixm = 0       # measure number
+        s.mdur = 0      # measure duration (nominal metre value in divisions)
+        s.divs = 0      # number of divisions per 1/4
+        s.mtr = 4,4     # meter
+
+    def reset (s):      # reset each measure
+        s.attr = ''     # measure signatures, tempo
+        s.lline = ''    # left barline, but only holds ':' at start of repeat, otherwise empty
+        s.rline = '|'   # right barline
+        s.lnum = ''     # (left) volta number
+
+class Note:
+    def __init__ (s, dur=0, n=None):
+        s.tijd = 0      # the time in XML division units
+        s.dur = dur     # duration of a note in XML divisions
+        s.fact = None   # time modification for tuplet notes (num, div)
+        s.tup = ['']    # start(s) and/or stop(s) of tuplet
+        s.tupabc = ''   # abc tuplet string to issue before note
+        s.beam = 0      # 1 = beamed
+        s.grace = 0     # 1 = grace note
+        s.before = []   # abc string that goes before the note/chord
+        s.after = ''    # the same after the note/chord
+        s.ns = n and [n] or []  # notes in the chord
+        s.lyrs = {}     # {number -> syllabe}
+        s.tab = None    # (string number, fret number)
+        s.ntdec = ''    # !string!, !courtesy!
+
+class Elem:
+    def __init__ (s, string):
+        s.tijd = 0      # the time in XML division units
+        s.str = string  # any abc string that is not a note
+
+class Counter:
+    def inc (s, key, voice): s.counters [key][voice] = s.counters [key].get (voice, 0) + 1
+    def clear (s, vnums):  # reset all counters
+        tups = list( zip (vnums.keys (), len (vnums) * [0]))
+        s.counters = {'note': dict (tups), 'nopr': dict (tups), 'nopt': dict (tups)}
+    def getv (s, key, voice): return s.counters[key][voice]
+    def prcnt (s, ip):  # print summary of all non zero counters
+        for iv in s.counters ['note']:
+            if s.getv ('nopr', iv) != 0:
+                info ( 'part %d, voice %d has %d skipped non printable notes' % (ip, iv, s.getv ('nopr', iv)))
+            if s.getv ('nopt', iv) != 0:
+                info ( 'part %d, voice %d has %d notes without pitch' % (ip, iv, s.getv ('nopt', iv)))
+            if s.getv ('note', iv) == 0: # no real notes counted in this voice
+                info ( 'part %d, skipped empty voice %d' % (ip, iv))
+
+class Music:
+    def __init__(s, options):
+        s.tijd = 0              # the current time
+        s.maxtime = 0           # maximum time in a measure
+        s.gMaten = []           # [voices,.. for all measures in a part]
+        s.gLyrics = []          # [{num: (abc_lyric_string, melis)},.. for all measures in a part]
+        s.vnums = {}            # all used voice id's in a part (xml voice id's == numbers)
+        s.cnt = Counter ()      # global counter object
+        s.vceCnt = 1            # the global voice count over all parts
+        s.lastnote = None       # the last real note record inserted in s.voices
+        s.bpl = options.b       # the max number of bars per line when writing abc
+        s.cpl = options.n       # the number of chars per line when writing abc
+        s.repbra = 0            # true if volta is used somewhere
+        s.nvlt = options.v      # no volta on higher voice numbers
+        s.jscript = options.j   # compatibility with javascript version
+
+    def initVoices (s, newPart=0):
+        s.vtimes, s.voices, s.lyrics = {}, {}, {}
+        for v in s.vnums:
+            s.vtimes [v] = 0    # {voice: the end time of the last item in each voice}
+            s.voices [v] = []   # {voice: [Note|Elem, ..]}
+            s.lyrics [v] = []   # {voice: [{num: syl}, ..]}
+        if newPart: s.cnt.clear (s.vnums)   # clear counters once per part
+
+    def incTime (s, dt):
+        s.tijd += dt
+        if s.tijd < 0: s.tijd = 0   # erroneous <backup> element
+        if s.tijd > s.maxtime: s.maxtime = s.tijd
+
+    def appendElemCv (s, voices, elem):
+        for v in voices:
+            s.appendElem (v, elem) # insert element in all voices
+
+    def insertElem (s, v, elem):    # insert at the start of voice v in the current measure
+        obj = Elem (elem)
+        obj.tijd = 0        # because voice is sorted later
+        s.voices [v].insert (0, obj)
+
+    def appendObj (s, v, obj, dur):
+        obj.tijd = s.tijd
+        s.voices [v].append (obj)
+        s.incTime (dur)
+        if s.tijd > s.vtimes[v]: s.vtimes[v] = s.tijd   # don't update for inserted earlier items
+
+    def appendElem (s, v, elem, tel=0):
+        s.appendObj (v, Elem (elem), 0)
+        if tel: s.cnt.inc ('note', v)   # count number of certain elements in each voice (in addition to notes)
+
+    def appendElemT (s, v, elem, tijd): # insert element at specified time
+        obj = Elem (elem)
+        obj.tijd = tijd
+        s.voices [v].append (obj)
+
+    def appendNote (s, v, note, noot):
+        note.ns.append (note.ntdec + noot)
+        s.appendObj (v, note, int (note.dur))
+        s.lastnote = note           # remember last note/rest for later modifications (chord, grace)
+        if noot != 'z' and noot != 'x':         # real notes and grace notes
+            s.cnt.inc ('note', v)   # count number of real notes in each voice
+            if not note.grace:                  # for every real note
+                s.lyrics[v].append (note.lyrs)  # even when it has no lyrics
+
+    def getLastRec (s, voice):
+        if s.gMaten: return s.gMaten[-1][voice][-1] # the last record in the last measure
+        return None                                 # no previous records in the first measure
+
+    def getLastMelis (s, voice, num):   # get melisma of last measure
+        if s.gLyrics:
+            lyrdict = s.gLyrics[-1][voice]  # the previous lyrics dict in this voice
+            if num in lyrdict: return lyrdict[num][1]   # lyrdict = num -> (lyric string, melisma)
+        return 0 # no previous lyrics in voice or line number
+
+    def addChord (s, note, noot):   # careful: we assume that chord notes follow immediately
+        for d in note.before:       # put all decorations before chord
+            if d not in s.lastnote.before:
+                s.lastnote.before += [d]
+        s.lastnote.ns.append (note.ntdec + noot)
+
+    def addBar (s, lbrk, m): # linebreak, measure data
+        if m.mdur and s.maxtime > m.mdur: info ('measure %d in part %d longer than metre' % (m.ixm+1, m.ixp+1))
+        s.tijd = s.maxtime              # the time of the bar lines inserted here
+        for v in s.vnums:
+            if m.lline or m.lnum:       # if left barline or left volta number
+                p = s.getLastRec (v)    # get the previous barline record
+                if p:                   # in measure 1 no previous measure is available
+                    x = p.str           # p.str is the ABC barline string
+                    if m.lline:         # append begin of repeat, m.lline == ':'
+                        x = (x + m.lline).replace (':|:','::').replace ('||','|')
+                    if s.nvlt == 3:     # add volta number only to lowest voice in part 0 
+                        if m.ixp + v == min (s.vnums): x += m.lnum
+                    elif m.lnum:        # new behaviour with I:repbra 0
+                        x += m.lnum     # add volta number(s) or text to all voices
+                        s.repbra = 1    # signal occurrence of a volta
+                    p.str = x           # modify previous right barline
+                elif m.lline:           # begin of new part and left repeat bar is required
+                    s.insertElem (v, '|:')
+            if lbrk:
+                p = s.getLastRec (v)    # get the previous barline record
+                if p: p.str += lbrk     # insert linebreak char after the barlines+volta
+            if m.attr:                  # insert signatures at front of buffer
+                s.insertElem (v, '%s' % m.attr)
+            s.appendElem (v, ' %s' % m.rline)   # insert current barline record at time maxtime
+            s.voices[v] = sortMeasure (s.voices[v], m)  # make all times consistent
+            lyrs = s.lyrics[v]          # [{number: sylabe}, .. for all notes]
+            lyrdict = {}                # {number: (abc_lyric_string, melis)} for this voice
+            nums = [num for d in lyrs for num in d.keys ()] # the lyrics numbers in this measure
+            maxNums = max (nums + [0])  # the highest lyrics number in this measure
+            for i in range (maxNums, 0, -1):
+                xs = [syldict.get (i, '') for syldict in lyrs]  # collect the syllabi with number i
+                melis = s.getLastMelis (v, i)  # get melisma from last measure
+                lyrdict [i] = abcLyr (xs, melis)
+            s.lyrics[v] = lyrdict       # {number: (abc_lyric_string, melis)} for this measure
+            mkBroken (s.voices[v])
+        s.gMaten.append (s.voices)
+        s.gLyrics.append (s.lyrics)
+        s.tijd = s.maxtime = 0
+        s.initVoices ()
+
+    def outVoices (s, divs, ip, isSib): # output all voices of part ip
+        vvmap = {}                  # xml voice number -> abc voice number (one part)
+        vnum_keys = list (s.vnums.keys ())
+        if s.jscript or isSib: vnum_keys.sort ()
+        lvc = min (vnum_keys or [1])	# lowest xml voice number of this part
+        for iv in vnum_keys:
+            if s.cnt.getv ('note', iv) == 0:    # no real notes counted in this voice
+                continue            # skip empty voices
+            if abcOut.denL: unitL = abcOut.denL # take the unit length from the -d option
+            else:           unitL = compUnitLength (iv, s.gMaten, divs) # compute the best unit length for this voice
+            abcOut.cmpL.append (unitL)  # remember for header output
+            vn, vl = [], {}         # for voice iv: collect all notes to vn and all lyric lines to vl
+            for im in range (len (s.gMaten)):
+                measure = s.gMaten [im][iv]
+                vn.append (outVoice (measure, divs [im], im, ip, unitL))
+                checkMelismas (s.gLyrics, s.gMaten, im, iv)
+                for n, (lyrstr, melis) in s.gLyrics [im][iv].items ():
+                    if n in vl:
+                        while len (vl[n]) < im: vl[n].append ('') # fill in skipped measures
+                        vl[n].append (lyrstr)
+                    else:
+                        vl[n] = im * [''] + [lyrstr]    # must skip im measures
+            for n, lyrs in vl.items (): # fill up possibly empty lyric measures at the end
+                mis = len (vn) - len (lyrs)
+                lyrs += mis * ['']
+            abcOut.add ('V:%d' % s.vceCnt)
+            if s.repbra:
+                if s.nvlt == 1 and s.vceCnt > 1: abcOut.add ('I:repbra 0')  # only volta on first voice
+                if s.nvlt == 2 and iv > lvc:     abcOut.add ('I:repbra 0')  # only volta on first voice of each part
+            if   s.cpl > 0:  s.bpl = 0      # option -n (max chars per line) overrules -b (max bars per line)
+            elif s.bpl == 0: s.cpl = 100    # the default: 100 chars per line
+            bn = 0                  # count bars
+            while vn:               # while still measures available
+                ib = 1
+                chunk = vn [0]
+                while ib < len (vn):
+                    if s.cpl > 0 and len (chunk) + len (vn [ib]) >= s.cpl: break    # line full (number of chars)
+                    if s.bpl > 0 and ib >= s.bpl: break                             # line full (number of bars)
+                    chunk += vn [ib]
+                    ib += 1
+                bn += ib
+                abcOut.add (chunk + ' %%%d' % bn)   # line with barnumer
+                del vn[:ib]         # chop ib bars
+                lyrlines = sorted (vl.items ())     # order the numbered lyric lines for output
+                for n, lyrs in lyrlines:
+                    abcOut.add ('w: ' + '|'.join (lyrs[:ib]) + '|')
+                    del lyrs[:ib]
+            vvmap [iv] = s.vceCnt   # xml voice number -> abc voice number
+            s.vceCnt += 1           # count voices over all parts
+        s.gMaten = []               # reset the follwing instance vars for each part
+        s.gLyrics = []
+        s.cnt.prcnt (ip+1)          # print summary of skipped items in this part
+        return vvmap
+
+class ABCoutput:
+    pagekeys = 'scale,pageheight,pagewidth,leftmargin,rightmargin,topmargin,botmargin'.split (',')
+    def __init__ (s, fnmext, pad, X, options):
+        s.fnmext = fnmext
+        s.outlist = []          # list of ABC strings
+        s.title = 'T:Title'
+        s.key = 'none'
+        s.clefs = {}            # clefs for all abc-voices
+        s.mtr = 'none'
+        s.tempo = 0             # 0 -> no tempo field
+        s.tempo_units = (1,4)	# note type of tempo direction
+        s.pad = pad             # the output path or none
+        s.X = X + 1             # the abc tune number
+        s.denL = options.d      # denominator of the unit length (L:) from -d option
+        s.volpan = int (options.m)  # 0 -> no %%MIDI, 1 -> only program, 2 -> all %%MIDI
+        s.cmpL = []             # computed optimal unit length for all voices
+        s.jscript = options.j   # compatibility with javascript version
+        s.tstep = options.t     # translate percmap to voicemap
+        s.stemless = 0          # use U:s=!stemless!
+        s.shiftStem = options.s # shift note heads 3 units left
+        if pad:
+            _, base_name = os.path.split (fnmext)
+            s.outfile = open (os.path.join (pad, base_name), 'w', encoding='utf-8')
+        else:   s.outfile = sys.stdout
+        if s.jscript: s.X = 1   # always X:1 in javascript version
+        s.pageFmt = {}
+        for k in s.pagekeys: s.pageFmt [k] = None
+        if len (options.p) == 7:
+            for k, v in zip (s.pagekeys, options.p):
+                try: s.pageFmt [k] = float (v)
+                except: info ('illegal float %s for %s', (k, v)); continue
+
+    def add (s, str):
+        s.outlist.append (str + '\n')   # collect all ABC output
+
+    def mkHeader (s, stfmap, partlist, midimap, vmpdct, koppen): # stfmap = [parts], part = [staves], stave = [voices]
+        accVce, accStf, staffs = [], [], stfmap[:]  # staffs is consumed
+        for x in partlist:              # collect partnames into accVce and staff groups into accStf
+            try: prgroupelem (x, ('', ''), '', stfmap, accVce, accStf)
+            except: info ('lousy musicxml: error in part-list')
+        staves = ' '.join (accStf)
+        clfnms = {}
+        for part, (partname, partabbrv) in zip (staffs, accVce):
+            if not part: continue       # skip empty part
+            firstVoice = part[0][0]     # the first voice number in this part
+            nm  = partname.replace ('\n','\\n').replace ('.:','.').strip (':')
+            snm = partabbrv.replace ('\n','\\n').replace ('.:','.').strip (':')
+            clfnms [firstVoice] = (nm and 'nm="%s"' % nm or '') + (snm and ' snm="%s"' % snm or '')
+        hd = ['X:%d\n%s\n' % (s.X, s.title)]
+        for i, k in enumerate (s.pagekeys):
+            if s.jscript and k in ['pageheight','topmargin', 'botmargin']: continue
+            if s.pageFmt [k] != None: hd.append ('%%%%%s %.2f%s\n' % (k, s.pageFmt [k], i > 0 and 'cm' or ''))
+        if staves and len (accStf) > 1: hd.append ('%%score ' + staves + '\n')
+        tempo = s.tempo and 'Q:%d/%d=%s\n' % (s.tempo_units [0], s.tempo_units [1], s.tempo) or ''  # default no tempo field
+        d = {}  # determine the most frequently occurring unit length over all voices
+        for x in s.cmpL: d[x] = d.get (x, 0) + 1
+        if s.jscript:   defLs = sorted (d.items (), key=lambda x: (-x[1], x[0])) # when tie (1) sort on key (0)
+        else:           defLs = sorted (d.items (), key=lambda x: -x[1])
+        defL = s.denL and s.denL or defLs [0][0] # override default unit length with -d option
+        hd.append ('L:1/%d\n%sM:%s\n' % (defL, tempo, s.mtr))
+        hd.append ('K:%s\n' % s.key)
+        if s.stemless: hd.append ('U:s=!stemless!\n')
+        vxs = sorted (vmpdct.keys ())
+        for vx in vxs: hd.extend (vmpdct [vx])
+        s.dojef = 0    # translate percmap to voicemap
+        for vnum, clef in s.clefs.items ():
+            ch, prg, vol, pan = midimap [vnum-1][:4]
+            dmap = midimap [vnum - 1][4:]   # map of abc percussion notes to midi notes
+            if dmap and 'perc' not in clef: clef = (clef + ' map=perc').strip ();
+            hd.append ('V:%d %s %s\n' % (vnum, clef, clfnms.get (vnum, '')))
+            if vnum in vmpdct:
+                hd.append ('%%%%voicemap tab%d\n' % vnum)
+                hd.append ('K:none\nM:none\n%%clef none\n%%staffscale 1.6\n%%flatbeams true\n%%stemdir down\n')
+            if 'perc' in clef: hd.append ('K:none\n');  # no key for a perc voice
+            if s.volpan > 1:    # option -m 2 -> output all recognized midi commands when needed and present in xml
+                if ch > 0 and ch != vnum: hd.append ('%%%%MIDI channel %d\n' % ch)
+                if prg > 0:  hd.append ('%%%%MIDI program %d\n' % (prg - 1))
+                if vol >= 0: hd.append ('%%%%MIDI control 7 %.0f\n' % vol)  # volume == 0 is possible ...
+                if pan >= 0: hd.append ('%%%%MIDI control 10 %.0f\n' % pan)
+            elif s.volpan > 0: # default -> only output midi program command when present in xml
+                if dmap and ch > 0: hd.append ('%%%%MIDI channel %d\n' % ch) # also channel if percussion part
+                if prg > 0:  hd.append ('%%%%MIDI program %d\n' % (prg - 1))
+            for abcNote, step, midiNote, notehead in dmap:
+                if not notehead: notehead = 'normal'
+                if abcMid (abcNote) != midiNote or abcNote != step:
+                    if s.volpan > 0: hd.append ('%%%%MIDI drummap %s %s\n' % (abcNote, midiNote))
+                    hd.append ('I:percmap %s %s %s %s\n' % (abcNote, step, midiNote, notehead))
+                    s.dojef = s.tstep
+            if defL != s.cmpL [vnum-1]: # only if computed unit length different from header
+                hd.append ('L:1/%d\n' % s.cmpL [vnum-1])
+        s.outlist = hd + s.outlist
+        if koppen:  # output SVG stuff needed for tablature
+            k1 = kopSvg.replace ('-2','-5') if s.shiftStem else kopSvg  # shift note heads 3 units left
+            k2 = kopSvg2.replace ('-2','-5') if s.shiftStem else kopSvg2
+            tb = tabSvg.replace ('-3','-6') if s.shiftStem else tabSvg
+            ks = sorted (koppen.keys ())                                # javascript compatibility
+            ks = [k2 % (k, k) if len (k) == 2 else k1 % (k, k) for k in ks]
+            tbs = map (lambda x: x.strip () + '\n', tb.splitlines ())   # javascript compatibility
+            s.outlist = tbs + ks + ['</defs>\n%%endsvg\n'] + s.outlist
+
+    def writeall (s):  # determine the required encoding of the entire ABC output
+        str = ''.join (s.outlist)
+        # print(str)
+        if s.dojef: str = perc2map (str)
+        if python3: s.outfile.write (str)
+        else:       s.outfile.write (str)
+        if s.pad: s.outfile.close ()                # close each file with -o option
+        else: s.outfile.write ('\n')                # add empty line between tunes on stdout
+        info ('%s written with %d voices' % (s.fnmext, len (s.clefs)), warn=0)
+
+#----------------
+# functions
+#----------------
+def abcLyr (xs, melis): # Convert list xs to abc lyrics.
+    if not ''.join (xs): return '', 0  # there is no lyrics in this measure
+    res = []
+    for x in xs:        # xs has for every note a lyrics syllabe or an empty string
+        if x == '':     # note without lyrics
+            if melis: x = '_'   # set melisma
+            else: x = '*'       # skip note
+        elif x.endswith ('_') and not x.endswith ('\_'): # start of new melisma
+            x = x.replace ('_', '') # remove and set melis boolean
+            melis = 1           # so next skips will become melisma
+        else: melis = 0         # melisma stops on first syllable
+        res.append (x)
+    return (' '.join (res), melis)
+
+def simplify (a, b):    # divide a and b by their greatest common divisor
+    x, y = a, b
+    while b: a, b = b, a % b
+    return x // a, y // a
+
+def abcdur (nx, divs, uL):      # convert an musicXML duration d to abc units with L:1/uL
+    if nx.dur == 0: return ''   # when called for elements without duration
+    num, den = simplify (uL * nx.dur, divs * 4) # L=1/8 -> uL = 8 units
+    if nx.fact:                 # apply tuplet time modification
+        numfac, denfac = nx.fact
+        num, den = simplify (num * numfac, den * denfac)
+    if den > 64:                # limit the denominator to a maximum of 64
+        x = float (num) / den; n = math.floor (x);  # when just above an integer n
+        if x - n < 0.1 * x: num, den = n, 1;        # round to n
+        num64 = 64. * num / den + 1.0e-15           # to get Python2 behaviour of round
+        num, den = simplify (int (round (num64)), 64)
+    if num == 1:
+        if   den == 1: dabc = ''
+        elif den == 2: dabc = '/'
+        else:          dabc = '/%d' % den
+    elif den == 1:     dabc = '%d' % num
+    else:              dabc = '%d/%d' % (num, den)
+    return dabc
+
+def abcMid (note):  # abc note -> midi pitch
+    r = re.search (r"([_^]*)([A-Ga-g])([',]*)", note)
+    if not r: return -1
+    acc, n, oct = r.groups ()
+    nUp = n.upper ()
+    p = 60 + [0,2,4,5,7,9,11]['CDEFGAB'.index (nUp)] + (12 if nUp != n else 0);
+    if acc: p += (1 if acc[0] == '^' else -1) * len (acc)
+    if oct: p += (12 if oct[0] == "'" else -12) * len (oct)
+    return p
+
+def staffStep (ptc, o, clef, tstep):
+    ndif = 0
+    if 'stafflines=1' in clef: ndif += 4                    # meaning of one line: E (xml) -> B (abc)
+    if not tstep and clef.startswith ('bass'): ndif += 12   # transpose bass -> treble (C3 -> A4)
+    if ndif:    # diatonic transposition == addition modulo 7
+        nm7 = 'C,D,E,F,G,A,B'.split (',')
+        n = nm7.index (ptc) + ndif
+        ptc, o = nm7 [n % 7], o + n // 7
+    if o > 4: ptc = ptc.lower ()
+    if o > 5: ptc = ptc + (o-5) * "'"
+    if o < 4: ptc = ptc + (4-o) * ","
+    return ptc
+
+def setKey (fifths, mode):
+    sharpness = ['Fb', 'Cb','Gb','Db','Ab','Eb','Bb','F','C','G','D','A', 'E', 'B', 'F#','C#','G#','D#','A#','E#','B#']
+    offTab = {'maj':8, 'ion':8, 'm':11, 'min':11, 'aeo':11, 'mix':9, 'dor':10, 'phr':12, 'lyd':7, 'loc':13, 'non':8}
+    mode = mode.lower ()[:3] # only first three chars, no case
+    key = sharpness [offTab [mode] + fifths] + (mode if offTab [mode] != 8 else '')
+    accs = ['F','C','G','D','A','E','B']
+    if fifths >= 0: msralts = dict (zip (accs[:fifths], fifths * [1]))
+    else:           msralts = dict (zip (accs[fifths:], -fifths * [-1]))
+    return key, msralts
+
+def insTup (ix, notes, fact):   # read one nested tuplet
+    tupcnt = 0
+    nx = notes [ix]
+    if 'start' in nx.tup:
+        nx.tup.remove ('start') # do recursive calls when starts remain
+    tix = ix                    # index of first tuplet note
+    fn, fd = fact               # xml time-mod of the higher level
+    fnum, fden = nx.fact        # xml time-mod of the current level
+    tupfact = fnum//fn, fden//fd  # abc time mod of this level
+    while ix < len (notes):
+        nx = notes [ix]
+        if isinstance (nx, Elem) or nx.grace:
+            ix += 1             # skip all non tuplet elements
+            continue
+        if 'start' in nx.tup:   # more nested tuplets to start
+            ix, tupcntR = insTup (ix, notes, tupfact)   # ix is on the stop note!
+            tupcnt += tupcntR
+        elif nx.fact:
+            tupcnt += 1         # count tuplet elements
+        if 'stop' in nx.tup:
+            nx.tup.remove ('stop')
+            break
+        if not nx.fact:         # stop on first non tuplet note
+            ix = lastix         # back to last tuplet note
+            break
+        lastix = ix
+        ix += 1
+    # put abc tuplet notation before the recursive ones
+    tup = (tupfact[0], tupfact[1], tupcnt)
+    if tup == (3, 2, 3): tupPrefix = '(3'
+    else:                tupPrefix = '(%d:%d:%d' % tup
+    notes [tix].tupabc = tupPrefix + notes [tix].tupabc
+    return ix, tupcnt           # ix is on the last tuplet note
+
+def mkBroken (vs):      # introduce broken rhythms (vs: one voice, one measure)
+    vs = [n for n in vs if isinstance (n, Note)]
+    i = 0
+    while i < len (vs) - 1:
+        n1, n2 = vs[i], vs[i+1]     # scan all adjacent pairs
+        # skip if note in tuplet or has no duration or outside beam
+        if not n1.fact and not n2.fact and n1.dur > 0 and n2.beam:
+            if n1.dur * 3 == n2.dur:
+                n2.dur = (2 * n2.dur) // 3
+                n1.dur = n1.dur * 2
+                n1.after = '<' + n1.after
+                i += 1              # do not chain broken rhythms
+            elif n2.dur * 3 == n1.dur:
+                n1.dur = (2 * n1.dur) // 3
+                n2.dur = n2.dur * 2
+                n1.after = '>' + n1.after
+                i += 1              # do not chain broken rhythms
+        i += 1
+
+def outVoice (measure, divs, im, ip, unitL):    # note/elem objects of one measure in one voice
+    ix = 0
+    while ix < len (measure):   # set all (nested) tuplet annotations
+        nx = measure [ix]
+        if isinstance (nx, Note) and nx.fact and not nx.grace:
+            ix, tupcnt = insTup (ix, measure, (1, 1))   # read one tuplet, insert annotation(s)
+        ix += 1 
+    vs = []
+    for nx in measure:
+        if isinstance (nx, Note):
+            durstr = abcdur (nx, divs, unitL)           # xml -> abc duration string
+            chord = len (nx.ns) > 1
+            cns = [nt[:-1] for nt in nx.ns if nt.endswith ('-')]
+            tie = ''
+            if chord and len (cns) == len (nx.ns):      # all chord notes tied
+                nx.ns = cns     # chord notes without tie
+                tie = '-'       # one tie for whole chord
+            s = nx.tupabc + ''.join (nx.before)
+            if chord: s += '['
+            for nt in nx.ns: s += nt
+            if chord: s += ']' + tie
+            if s.endswith ('-'): s, tie = s[:-1], '-'   # split off tie
+            s += durstr + tie   # and put it back again
+            s += nx.after
+            nospace = nx.beam
+        else:
+            if isinstance (nx.str, listtype): nx.str = nx.str [0]
+            s = nx.str
+            nospace = 1
+        if nospace: vs.append (s)
+        else: vs.append (' ' + s)
+    vs = ''.join (vs)   # ad hoc: remove multiple pedal directions
+    while vs.find ('!ped!!ped!') >= 0: vs = vs.replace ('!ped!!ped!','!ped!')
+    while vs.find ('!ped-up!!ped-up!') >= 0: vs = vs.replace ('!ped-up!!ped-up!','!ped-up!')
+    while vs.find ('!8va(!!8va)!') >= 0: vs = vs.replace ('!8va(!!8va)!','')    # remove empty ottava's
+    return vs
+
+def sortMeasure (voice, m):
+    voice.sort (key=lambda o: o.tijd)   # sort on time
+    time = 0
+    v = []
+    rs = []                            # holds rests in between notes
+    for i, nx in enumerate (voice):    # establish sequentiality
+        if nx.tijd > time and chkbug (nx.tijd - time, m):
+            v.append (Note (nx.tijd - time, 'x'))   # fill hole with invisble rest
+            rs.append (len (v) - 1)
+        if isinstance (nx, Elem):
+            if nx.tijd < time: nx.tijd = time # shift elems without duration to where they fit
+            v.append (nx)
+            time = nx.tijd
+            continue
+        if nx.tijd < time:                  # overlapping element
+            if nx.ns[0] == 'z': continue    # discard overlapping rest
+            if v[-1].tijd <= nx.tijd:       # we can do something
+                if v[-1].ns[0] == 'z':      # shorten rest
+                    v[-1].dur = nx.tijd - v[-1].tijd
+                    if v[-1].dur == 0: del v[-1]        # nothing left
+                    info ('overlap in part %d, measure %d: rest shortened' % (m.ixp+1, m.ixm+1))
+                else:                       # make a chord of overlap
+                    v[-1].ns += nx.ns
+                    info ('overlap in part %d, measure %d: added chord' % (m.ixp+1, m.ixm+1))
+                    nx.dur = (nx.tijd + nx.dur) - time  # the remains
+                    if nx.dur <= 0: continue            # nothing left
+                    nx.tijd = time          # append remains
+            else:                           # give up
+                info ('overlapping notes in one voice! part %d, measure %d, note %s discarded' % (m.ixp+1, m.ixm+1, isinstance (nx, Note) and nx.ns or nx.str))
+                continue
+        v.append (nx)
+        if isinstance (nx, Note):
+            if nx.ns [0] in 'zx':
+                rs.append (len (v) - 1)     # remember rests between notes
+            elif len (rs):
+                if nx.beam and not nx.grace:    # copy beam into rests
+                    for j in rs: v[j].beam = nx.beam
+                rs = []                     # clear rests on each note
+        time = nx.tijd + nx.dur
+    #   when a measure contains no elements and no forwards -> no incTime -> s.maxtime = 0 -> right barline
+    #   is inserted at time == 0 (in addbar) and is only element in the voice when sortMeasure is called
+    if time == 0: info ('empty measure in part %d, measure %d, it should contain at least a rest to advance the time!' % (m.ixp+1, m.ixm+1))
+    return v
+
+def getPartlist (ps):   # correct part-list (from buggy xml-software)
+    xs = [] # the corrected part-list
+    e = []  # stack of opened part-groups
+    for x in list (ps): # insert missing stops, delete double starts
+        if x.tag ==  'part-group':
+            num, type = x.get ('number'), x.get ('type')
+            if type == 'start':
+                if num in e:    # missing stop: insert one
+                    xs.append (E.Element ('part-group', number = num, type = 'stop'))
+                    xs.append (x)
+                else:           # normal start
+                    xs.append (x)
+                    e.append (num)
+            else:
+                if num in e:    # normal stop
+                    e.remove (num)
+                    xs.append (x)
+                else: pass      # double stop: skip it
+        else: xs.append (x)
+    for num in reversed (e):    # fill missing stops at the end
+        xs.append (E.Element ('part-group', number = num, type = 'stop'))
+    return xs
+
+def parseParts (xs, d, e):  # -> [elems on current level], rest of xs
+    if not xs: return [],[]
+    x = xs.pop (0)
+    if x.tag == 'part-group':
+        num, type = x.get ('number'), x.get ('type')
+        if type == 'start': # go one level deeper
+            s = [x.findtext (n, '') for n in ['group-symbol','group-barline','group-name','group-abbreviation']]
+            d [num] = s     # remember groupdata by group number
+            e.append (num)  # make stack of open group numbers
+            elemsnext, rest1 = parseParts (xs, d, e) # parse one level deeper to next stop
+            elems, rest2 = parseParts (rest1, d, e)  # parse the rest on this level
+            return [elemsnext] + elems, rest2
+        else:               # stop: close level and return group-data
+            nums = e.pop () # last open group number in stack order
+            if xs and xs[0].get ('type') == 'stop':     # two consequetive stops
+                if num != nums:                         # in the wrong order (tempory solution)
+                    d[nums], d[num] = d[num], d[nums]   # exchange values    (only works for two stops!!!)
+            sym = d[num]    # retrieve an return groupdata as last element of the group
+            return [sym], xs
+    else:
+        elems, rest = parseParts (xs, d, e) # parse remaining elements on current level
+        name = x.findtext ('part-name',''), x.findtext ('part-abbreviation','')
+        return [name] + elems, rest
+
+def bracePart (part):       # put a brace on multistaff part and group voices
+    if not part: return []  # empty part in the score
+    brace = []
+    for ivs in part:
+        if len (ivs) == 1:  # stave with one voice
+            brace.append ('%s' % ivs[0])
+        else:               # stave with multiple voices
+            brace += ['('] + ['%s' % iv for iv in ivs] + [')']
+        brace.append ('|')
+    del brace[-1]           # no barline at the end
+    if len (part) > 1:
+        brace = ['{'] + brace + ['}']
+    return brace
+
+def prgroupelem (x, gnm, bar, pmap, accVce, accStf):    # collect partnames (accVce) and %%score map (accStf)
+    if type (x) == tupletype:   # partname-tuple = (part-name, part-abbrev)
+        y = pmap.pop (0)
+        if gnm[0]: x = [n1 + ':' + n2 for n1, n2 in zip (gnm, x)]   # put group-name before part-name
+        accVce.append (x)
+        accStf.extend (bracePart (y))
+    elif len (x) == 2 and type (x[0]) == tupletype: # misuse of group just to add extra name to stave
+        y = pmap.pop (0)
+        nms = [n1 + ':' + n2 for n1, n2 in zip (x[0], x[1][2:])]    # x[0] = partname-tuple, x[1][2:] = groupname-tuple
+        accVce.append (nms)
+        accStf.extend (bracePart (y))
+    else:
+        prgrouplist (x, bar, pmap, accVce, accStf)
+
+def prgrouplist (x, pbar, pmap, accVce, accStf):    # collect partnames, scoremap for a part-group
+    sym, bar, gnm, gabbr = x[-1]    # bracket symbol, continue barline, group-name-tuple
+    bar = bar == 'yes' or pbar      # pbar -> the parent has bar
+    accStf.append (sym == 'brace' and '{' or '[')
+    for z in x[:-1]:
+        prgroupelem (z, (gnm, gabbr), bar, pmap, accVce, accStf)
+        if bar: accStf.append ('|')
+    if bar: del accStf [-1]         # remove last one before close
+    accStf.append (sym == 'brace' and '}' or ']')
+
+def compUnitLength (iv, maten, divs):   # compute optimal unit length
+    uLmin, minLen = 0, max_int
+    for uL in [4,8,16]:     # try 1/4, 1/8 and 1/16
+        vLen = 0            # total length of abc duration strings in this voice
+        for im, m in enumerate (maten): # all measures
+            for e in m[iv]: # all notes in voice iv
+                if isinstance (e, Elem) or e.dur == 0: continue # no real durations
+                vLen += len (abcdur (e, divs [im], uL))  # add len of duration string
+        if vLen < minLen: uLmin, minLen = uL, vLen  # remember the smallest
+    return uLmin
+
+def doSyllable (syl):
+    txt = ''
+    for e in syl:
+        if   e.tag == 'elision': txt += '~'
+        elif e.tag == 'text':   # escape - and space characters
+            txt += (e.text or '').replace ('_','\_').replace('-', r'\-').replace(' ', '~')
+    if not txt: return txt
+    if syl.findtext('syllabic') in ['begin', 'middle']: txt += '-'
+    if syl.find('extend') is not None:                  txt += '_'
+    return txt
+
+def checkMelismas (lyrics, maten, im, iv):
+    if im == 0: return
+    maat = maten [im][iv]               # notes of the current measure
+    curlyr = lyrics [im][iv]            # lyrics dict of current measure
+    prvlyr = lyrics [im-1][iv]          # lyrics dict of previous measure
+    for n, (lyrstr, melis) in prvlyr.items ():  # all lyric numbers in the previous measure
+        if n not in curlyr and melis:   # melisma required, but no lyrics present -> make one!
+            ms = getMelisma (maat)      # get a melisma for the current measure
+            if ms: curlyr [n] = (ms, 0) # set melisma as the n-th lyrics of the current measure
+
+def getMelisma (maat):                  # get melisma from notes in maat
+    ms = []
+    for note in maat:                   # every note should get an underscore
+        if not isinstance (note, Note): continue    # skip Elem's
+        if note.grace: continue         # skip grace notes
+        if note.ns [0] in 'zx': break   # stop on first rest
+        ms.append ('_')
+    return ' '.join (ms)
+
+def perc2map (abcIn):
+    fillmap = {'diamond':1, 'triangle':1, 'square':1, 'normal':1};
+    abc = map (lambda x: x.strip (), percSvg.splitlines ())
+    id='default'
+    maps = {'default': []};
+    dmaps = {'default': []}
+    r1 = re.compile (r'V:\s*(\S+)')
+    ls = abcIn.splitlines ()
+    for x in ls:
+        if 'I:percmap' in x:
+            noot, step, midi, kop = map (lambda x: x.strip (), x.split ()[1:])
+            if kop in fillmap: kop = kop + '+' + ',' + kop
+            x = '%%%%map perc%s %s print=%s midi=%s heads=%s' % (id, noot, step, midi, kop)
+            maps [id].append (x)
+        if '%%MIDI' in x: dmaps [id].append (x)
+        if 'V:' in x:
+            r = r1.match (x)
+            if r:
+                id = r.group (1);
+                if id not in maps: maps [id] = []; dmaps [id] = []
+    ids = sorted (maps.keys ())
+    for id in ids: abc += maps [id]
+    id='default'
+    for x in ls:
+        if 'I:percmap' in x: continue
+        if '%%MIDI' in x: continue
+        if 'V:' in x or 'K:' in x:
+            r = r1.match (x)
+            if r: id = r.group (1)
+            abc.append (x)
+            if id in dmaps and len (dmaps [id]) > 0: abc.extend (dmaps [id]); del dmaps [id]
+            if 'perc' in x and 'map=' not in x: x += ' map=perc';
+            if 'map=perc' in x and len (maps [id]) > 0: abc.append ('%%voicemap perc' + id);
+            if 'map=off' in x: abc.append ('%%voicemap');            
+        else:
+            abc.append (x)
+    return '\n'.join (abc) + '\n'
+
+def addoct (ptc, o):    # xml staff step, xml octave number
+    p = ptc
+    if o > 4: p = ptc.lower ()
+    if o > 5: p = p + (o-5) * "'"
+    if o < 4: p = p + (4-o) * ","
+    return p            # abc pitch == abc note without accidental
+
+def chkbug (dt, m):
+    if dt > m.divs / 16: return 1   # duration should be > 1/64 note
+    info ('MuseScore bug: incorrect duration, smaller then 1/64! in measure %d, part %d' % (m.ixm, m.ixp))
+    return 0
+
+#----------------
+# parser
+#----------------
+class Parser:
+    note_alts = [   # 3 alternative notations of the same note for tablature mapping
+        [x.strip () for x in '=C,  ^C, =D, ^D, =E, =F, ^F, =G, ^G, =A, ^A, =B'.split (',')],
+        [x.strip () for x in '^B,  _D,^^C, _E, _F, ^E, _G,^^F, _A,^^G, _B, _C'.split (',')],
+        [x.strip () for x in '__D,^^B,__E,__F,^^D,__G,^^E,__A,_/A,__B,__C,^^A'.split (',')] ]
+    step_map = {'C':0,'D':2,'E':4,'F':5,'G':7,'A':9,'B':11}
+    def __init__ (s, options):
+        # unfold repeats, number of chars per line, credit filter level, volta option
+        s.slurBuf = {}    # dict of open slurs keyed by slur number
+        s.dirStk = {}     # {direction-type + number -> (type, voice | time)} dict for proper closing
+        s.ingrace = 0     # marks a sequence of grace notes
+        s.msc = Music (options)  # global music data abstraction
+        s.unfold = options.u    # turn unfolding repeats on
+        s.ctf = options.c       # credit text filter level
+        s.gStfMap = []    # [[abc voice numbers] for all parts]
+        s.midiMap = []    # midi-settings for each abc voice, in order
+        s.drumInst = {}   # inst_id -> midi pitch for channel 10 notes
+        s.drumNotes = {}  # (xml voice, abc note) -> (midi note, note head)
+        s.instMid = []    # [{inst id -> midi-settings} for all parts]
+        s.midDflt = [-1,-1,-1,-91] # default midi settings for channel, program, volume, panning
+        s.msralts = {}    # xml-notenames (without octave) with accidentals from the key
+        s.curalts = {}    # abc-notenames (with voice number) with passing accidentals
+        s.stfMap = {}     # xml staff number -> [xml voice number]
+        s.vce2stf = {}    # xml voice number -> allocated staff number
+        s.clefMap = {}    # xml staff number -> abc clef (for header only)
+        s.curClef = {}    # xml staff number -> current abc clef
+        s.stemDir = {}    # xml voice number -> current stem direction
+        s.clefOct = {}    # xml staff number -> current clef-octave-change
+        s.curStf = {}     # xml voice number -> current xml staff number
+        s.nolbrk = options.x;   # generate no linebreaks ($)
+        s.jscript = options.j   # compatibility with javascript version
+        s.ornaments = sorted (note_ornamentation_map.items ())
+        s.doPageFmt = len (options.p) == 1 # translate xml page format
+        s.tstep = options.t     # clef determines step on staff (percussion)
+        s.dirtov1 = options.v1  # all directions to first voice of staff
+        s.ped = options.ped     # render pedal directions
+        s.wstems = options.stm  # translate stem elements
+        s.pedVce = None   # voice for pedal directions
+        s.repeat_str = {} # staff number -> [measure number, repeat-text]
+        s.tabVceMap = {}  # abc voice num -> [%%map ...] for tab voices
+        s.koppen = {}     # noteheads needed for %%map
+
+    def matchSlur (s, type2, n, v2, note2, grace, stopgrace): # match slur number n in voice v2, add abc code to before/after
+        if type2 not in ['start', 'stop']: return   # slur type continue has no abc equivalent
+        if n == None: n = '1'
+        if n in s.slurBuf:
+            type1, v1, note1, grace1 = s.slurBuf [n]
+            if type2 != type1:              # slur complete, now check the voice
+                if v2 == v1:                # begins and ends in the same voice: keep it
+                    if type1 == 'start' and (not grace1 or not stopgrace):  # normal slur: start before stop and no grace slur
+                        note1.before = ['('] + note1.before # keep left-right order!
+                        note2.after += ')'
+                    # no else: don't bother with reversed stave spanning slurs
+                del s.slurBuf [n]           # slur finished, remove from stack
+            else:                           # double definition, keep the last
+                info ('double slur numbers %s-%s in part %d, measure %d, voice %d note %s, first discarded' % (type2, n, s.msr.ixp+1, s.msr.ixm+1, v2, note2.ns))
+                s.slurBuf [n] = (type2, v2, note2, grace)
+        else:                               # unmatched slur, put in dict
+            s.slurBuf [n] = (type2, v2, note2, grace)
+    
+    def doNotations (s, note, nttn, isTab):
+        for key, val in s.ornaments:
+            if nttn.find (key) != None: note.before += [val]  # just concat all ornaments
+        trem = nttn.find ('ornaments/tremolo')
+        if trem != None:
+            type = trem.get ('type')
+            if type == 'single':
+                note.before.insert (0, '!%s!' % (int (trem.text) * '/'))
+            else:
+                note.fact = None    # no time modification in ABC
+                if s.tstep:         # abc2svg version
+                    if type == 'stop': note.before.insert (0, '!trem%s!' % trem.text);
+                else:               # abc2xml version
+                    if type == 'start': note.before.insert (0, '!%s-!' % (int (trem.text) * '/'));
+        fingering = nttn.findall ('technical/fingering')
+        for finger in fingering:    # handle multiple finger annotations
+            if not isTab: note.before += ['!%s!' % finger.text] # fingering goes before chord (addChord)
+        snaar = nttn.find ('technical/string')
+        if snaar != None and isTab:
+            if s.tstep:
+                fret = nttn.find ('technical/fret')
+                if fret != None: note.tab = (snaar.text, fret.text)
+            else:
+                deco = '!%s!' % snaar.text  # no double string decos (bug in musescore)
+                if deco not in note.ntdec: note.ntdec += deco
+        wvln = nttn.find ('ornaments/wavy-line')
+        if wvln != None:
+            if   wvln.get ('type') == 'start': note.before = ['!trill(!'] + note.before # keep left-right order!
+            elif wvln.get ('type') == 'stop': note.before = ['!trill)!'] + note.before
+        glis = nttn.find ('glissando')
+        if glis == None: glis = nttn.find ('slide') # treat slide as glissando
+        if glis != None:
+            lt = '~' if glis.get ('line-type') =='wavy' else '-'
+            if   glis.get ('type') == 'start': note.before = ['!%s(!' % lt] + note.before # keep left-right order!
+            elif glis.get ('type') == 'stop': note.before = ['!%s)!' % lt] + note.before
+
+    def tabnote (s, alt, ptc, oct, v, ntrec):
+        p = s.step_map [ptc] + int (alt or '0') # p in -2 .. 13
+        if p > 11: oct += 1             # octave correction
+        if p < 0: oct -= 1
+        p = p % 12                      # remap p into 0..11
+        snaar_nw, fret_nw = ntrec.tab   # the computed/annotated allocation of nt
+        for i in range (4):             # support same note on 4 strings
+            na = s.note_alts [i % 3] [p]    # get alternative representation of same note
+            o = oct
+            if na in ['^B', '^^B']: o -= 1  # because in adjacent octave
+            if na in ['_C', '__C']: o += 1
+            if '/' in na or i == 3: o = 9   # emergency notation for 4th string case
+            nt = addoct (na, o)
+            snaar, fret = s.tabmap.get ((v, nt), ('', ''))  # the current allocation of nt
+            if not snaar: break             # note not yet allocated
+            if snaar_nw == snaar: return nt # use present allocation
+            if i == 3:                  # new allocaion needed but none is free
+                fmt = 'rejected: voice %d note %3s string %s fret %2s remains: string %s fret %s'
+                info (fmt % (v, nt, snaar_nw, fret_nw, snaar, fret), 1)
+                ntrec.tab = (snaar, fret)
+        s.tabmap [v, nt] = ntrec.tab    # for tablature map (voice, note) -> (string, fret)
+        return nt                       # ABC code always in key C (with midi pitch alterations)
+
+    def ntAbc (s, ptc, oct, note, v, ntrec, isTab): # pitch, octave -> abc notation
+        acc2alt = {
+            'double-flat': -2,
+            'flat-flat': -2,
+            'flat': -1,
+            'natural-flat': -1,
+            'natural': 0,
+            'sharp': 1,
+            'natural-sharp': 1,
+            'sharp-sharp': 2,
+            'double-sharp': 2
+        }
+        oct += s.clefOct.get (s.curStf [v], 0)  # minus clef-octave-change value
+        acc = note.findtext ('accidental')  # should be the notated accidental
+        alt = note.findtext ('pitch/alter') # pitch alteration (midi)
+        if ntrec.tab: return s.tabnote (alt, ptc, oct, v, ntrec)    # implies s.tstep is true (options.t was given)
+        elif isTab and s.tstep:
+            nt = ['__','_','','^','^^'][int (alt or '0') + 2] + addoct (ptc, oct)
+            info ('no string notation found for note %s in voice %d' % (nt, v), 1)
+        p = addoct (ptc, oct)
+        if alt == None and s.msralts.get (ptc, 0): alt = 0  # no alt but key implies alt -> natural!!
+        if alt == None and (p, v) in s.curalts: alt = 0     # no alt but previous note had one -> natural!!
+        if acc == None and alt == None: return p    # no acc, no alt
+        elif acc != None:
+            alt = acc2alt [acc]      # acc takes precedence over the pitch here!
+        else:   # now see if we really must add an accidental
+            alt = int (float (alt))
+            if (p, v) in s.curalts:  # the note in this voice has been altered before
+                if alt == s.curalts [(p, v)]: return p      # alteration still the same
+            elif alt == s.msralts.get (ptc, 0): return p    # alteration implied by the key
+            tieElms = note.findall ('tie') + note.findall ('notations/tied')    # in xml we have separate notated ties and playback ties
+            if 'stop' in [e.get ('type') for e in tieElms]: return p    # don't alter tied notes
+            info ('accidental %d added in part %d, measure %d, voice %d note %s' % (alt, s.msr.ixp+1, s.msr.ixm+1, v+1, p))
+        s.curalts [(p, v)] = alt
+        p = ['__','_','=','^','^^'][alt+2] + p # and finally ... prepend the accidental
+        return p
+
+    def doNote (s, n):    # parse a musicXML note tag
+        note = Note ()
+        v = int (n.findtext ('voice', '1'))
+        if s.isSib: v += 100 * int (n.findtext ('staff', '1'))  # repair bug in Sibelius
+        chord = n.find ('chord') != None
+        p = n.findtext ('pitch/step') or n.findtext ('unpitched/display-step')
+        o = n.findtext ('pitch/octave') or n.findtext ('unpitched/display-octave')
+        r = n.find ('rest')
+        numer = n.findtext ('time-modification/actual-notes')
+        if numer:
+            denom = n.findtext ('time-modification/normal-notes')
+            note.fact = (int (numer), int (denom))
+        note.tup = [x.get ('type') for x in n.findall ('notations/tuplet')]
+        dur = n.findtext ('duration')
+        grc = n.find ('grace')
+        note.grace = grc != None
+        note.before, note.after = [], '' # strings with ABC stuff that goes before or after a note/chord
+        if note.grace and not s.ingrace: # open a grace sequence
+            s.ingrace = 1
+            note.before = ['{']
+            if grc.get ('slash') == 'yes': note.before += ['/'] # acciaccatura
+        stopgrace = not note.grace and s.ingrace
+        if stopgrace:                   # close the grace sequence
+            s.ingrace = 0
+            s.msc.lastnote.after += '}' # close grace on lastenote.after
+        if dur == None or note.grace: dur = 0
+        if r == None and n.get ('print-object') == 'no':
+            if chord: return
+            r = 1  # turn invisible notes (that advance the time) into invisible rests
+        note.dur = int (dur)
+        if r == None and (not p or not o):  # not a rest and no pitch
+            s.msc.cnt.inc ('nopt', v)       # count unpitched notes
+            o, p = 5,'E'                    # make it an E5 ??
+        isTab = s.curClef and s.curClef.get (s.curStf [v], '').startswith ('tab')
+        nttn = n.find ('notations')     # add ornaments
+        if nttn != None: s.doNotations (note, nttn, isTab)
+        e = n.find ('stem') if r == None else None  # no !stemless! before rest
+        if e != None and e.text == 'none' and (not isTab or v in s.hasStems or s.tstep):
+            note.before += ['!stemless!']; abcOut.stemless = 0; # ???????????U???????????!stemless!
+            # note.before += ['s']; abcOut.stemless = 1;
+        e = n.find ('accidental')
+        if e != None and e.get ('parentheses') == 'yes': note.ntdec += '!courtesy!'
+        if r != None: noot = 'x' if n.get ('print-object') == 'no' or isTab else 'z'
+        else: noot = s.ntAbc (p, int (o), n, v, note, isTab)
+        if n.find ('unpitched') != None:
+            clef = s.curClef [s.curStf [v]]     # the current clef for this voice
+            step = staffStep (p, int (o), clef, s.tstep)        # (clef independent) step value of note on the staff
+            instr = n.find ('instrument')
+            instId = instr.get ('id') if instr != None else 'dummyId'
+            midi = s.drumInst.get (instId, abcMid (noot))
+            nh =  n.findtext ('notehead', '').replace (' ','-') # replace spaces in xml notehead names for percmap
+            if nh == 'x': noot = '^' + noot.replace ('^','').replace ('_','')
+            if nh in ['circle-x','diamond','triangle']: noot = '_' + noot.replace ('^','').replace ('_','')
+            if nh and n.find ('notehead').get ('filled','') == 'yes': nh += '+'
+            if nh and n.find ('notehead').get ('filled','') == 'no': nh += '-'
+            s.drumNotes [(v, noot)] = (step, midi, nh) # keep data for percussion map
+        tieElms = n.findall ('tie') + n.findall ('notations/tied')  # in xml we have separate notated ties and playback ties
+        if 'start' in [e.get ('type') for e in tieElms]:            # n can have stop and start tie
+            noot = noot + '-'
+        note.beam = sum ([1 for b in n.findall('beam') if b.text in ['continue', 'end']]) + int (note.grace)
+        lyrlast = 0; rsib = re.compile (r'^.*verse')
+        for e in n.findall ('lyric'):
+            lyrnum = int (rsib.sub ('', e.get ('number', '1'))) # also do Sibelius numbers
+            if lyrnum == 0: lyrnum = lyrlast + 1                # and correct Sibelius bugs
+            else: lyrlast = lyrnum
+            note.lyrs [lyrnum] = doSyllable (e)
+        stemdir = n.findtext ('stem')
+        if s.wstems and (stemdir == 'up' or stemdir == 'down'):
+            if stemdir != s.stemDir.get (v, ''):
+                s.stemDir [v] = stemdir
+                s.msc.appendElem (v, '[I:stemdir %s]' % stemdir)
+        if chord: s.msc.addChord (note, noot)
+        else:
+            xmlstaff = int (n.findtext ('staff', '1'))
+            if s.curStf [v] != xmlstaff:    # the note should go to another staff
+                dstaff = xmlstaff - s.curStf [v]    # relative new staff number
+                s.curStf [v] = xmlstaff     # remember the new staff for this voice
+                s.msc.appendElem (v, '[I:staff %+d]' % dstaff)  # insert a move before the note
+            s.msc.appendNote (v, note, noot)
+        for slur in n.findall ('notations/slur'):   # s.msc.lastnote points to the last real note/chord inserted above
+            s.matchSlur (slur.get ('type'), slur.get ('number'), v, s.msc.lastnote, note.grace, stopgrace) # match slur definitions
+
+    def doAttr (s, e):    # parse a musicXML attribute tag
+        teken = {'C1':'alto1','C2':'alto2','C3':'alto','C4':'tenor','F4':'bass','F3':'bass3','G2':'treble','TAB':'tab','percussion':'perc'}
+        dvstxt = e.findtext ('divisions')
+        if dvstxt: s.msr.divs = int (dvstxt)
+        steps = int (e.findtext ('transpose/chromatic', '0'))   # for transposing instrument
+        fifths = e.findtext ('key/fifths')
+        first = s.msc.tijd == 0 and s.msr.ixm == 0  # first attributes in first measure
+        if fifths:
+            key, s.msralts = setKey (int (fifths), e.findtext ('key/mode','major'))
+            if first and not steps and abcOut.key == 'none':
+                abcOut.key = key                # first measure -> header, if not transposing instrument or percussion part!
+            elif key != abcOut.key or not first:
+                s.msr.attr += '[K:%s]' % key    # otherwise -> voice
+        beats = e.findtext ('time/beats')
+        if beats:
+            unit = e.findtext ('time/beat-type')
+            mtr = beats + '/' + unit
+            if first: abcOut.mtr = mtr          # first measure -> header
+            else: s.msr.attr += '[M:%s]' % mtr  # otherwise -> voice
+            s.msr.mtr = int (beats), int (unit)
+        s.msr.mdur = (s.msr.divs * s.msr.mtr[0] * 4) // s.msr.mtr[1]   # duration of measure in xml-divisions
+        for ms in e.findall('measure-style'):
+            n = int (ms.get ('number', '1'))    # staff number
+            voices = s.stfMap [n]               # all voices of staff n
+            for mr in ms.findall('measure-repeat'):
+                ty = mr.get('type')
+                if ty == 'start':               # remember start measure number and text voor each staff
+                    s.repeat_str [n] = [s.msr.ixm, mr.text]
+                    for v in voices:            # insert repeat into all voices, value will be overwritten at stop
+                        s.msc.insertElem (v, s.repeat_str [n])
+                elif ty == 'stop':              # calculate repeat measure count for this staff n
+                    start_ix, text_ = s.repeat_str [n]
+                    repeat_count = s.msr.ixm - start_ix
+                    if text_:
+                        mid_str =  "%s " % text_
+                        repeat_count /= int (text_)
+                    else:
+                        mid_str = ""            # overwrite repeat with final string
+                    s.repeat_str [n][0] = '[I:repeat %s%d]' % (mid_str, repeat_count)
+                    del s.repeat_str [n]        # remove closed repeats
+        toct = e.findtext ('transpose/octave-change', '')
+        if toct: steps += 12 * int (toct)       # extra transposition of toct octaves
+        for clef in e.findall ('clef'):         # a part can have multiple staves
+            n = int (clef.get ('number', '1'))  # local staff number for this clef
+            sgn = clef.findtext ('sign')
+            line = clef.findtext ('line', '') if sgn not in ['percussion','TAB'] else ''
+            cs = teken.get (sgn + line, '')
+            oct = clef.findtext ('clef-octave-change', '') or '0'
+            if oct: cs += {-2:'-15', -1:'-8', 1:'+8', 2:'+15'}.get (int (oct), '')
+            s.clefOct [n] = -int (oct);         # xml playback pitch -> abc notation pitch
+            if steps: cs += ' transpose=' + str (steps)
+            stfdtl = e.find ('staff-details')
+            if stfdtl and int (stfdtl.get ('number', '1')) == n:
+                lines = stfdtl.findtext ('staff-lines')
+                if lines:
+                    lns= '|||' if lines == '3' and sgn == 'TAB' else lines
+                    cs += ' stafflines=%s' % lns
+                    s.stafflines = int (lines)  # remember for tab staves
+                strings = stfdtl.findall ('staff-tuning')
+                if strings:
+                    tuning = [st.findtext ('tuning-step') + st.findtext ('tuning-octave') for st in strings]
+                    cs += ' strings=%s' % ','.join (tuning) 
+                capo = stfdtl.findtext ('capo')
+                if capo: cs += ' capo=%s' % capo
+            s.curClef [n] = cs                  # keep track of current clef (for percmap)
+            if first: s.clefMap [n] = cs        # clef goes to header (where it is mapped to voices)
+            else:
+                voices = s.stfMap[n]            # clef change to all voices of staff n
+                for v in voices:
+                    if n != s.curStf [v]:       # voice is not at its home staff n
+                        dstaff = n - s.curStf [v]
+                        s.curStf [v] = n        # reset current staff at start of measure to home position
+                        s.msc.appendElem (v, '[I:staff %+d]' % dstaff)
+                    s.msc.appendElem (v, '[K:%s]' % cs)
+
+    def findVoice (s, i, es):
+        stfnum = int (es[i].findtext ('staff',1))   # directions belong to a staff
+        vs = s.stfMap [stfnum]                      # voices in this staff
+        v1 = vs [0] if vs else 1                    # directions to first voice of staff
+        if s.dirtov1: return stfnum, v1, v1         # option --v1
+        for e in es [i+1:]:                         # or to the voice of the next note
+            if e.tag == 'note':
+                v = int (e.findtext ('voice', '1'))
+                if s.isSib: v += 100 * int (e.findtext ('staff', '1'))  # repair bug in Sibelius
+                stf = s.vce2stf [v]                 # use our own staff allocation
+                return stf, v, v1                   # voice of next note, first voice of staff
+            if e.tag == 'backup': break
+        return stfnum, v1, v1                       # no note found, fall back to v1
+
+    def doDirection (s, e, i, es): # parse a musicXML direction tag
+        def addDirection (x, vs, tijd, stfnum):
+            if not x: return
+            vs = s.stfMap [stfnum] if '!8v' in x else [vs]  # ottava's go to all voices of staff
+            for v in vs:
+                if tijd != None:   # insert at time of encounter
+                    s.msc.appendElemT (v, x.replace ('(',')').replace ('ped','ped-up'), tijd)
+                else:
+                    s.msc.appendElem (v, x)
+        def startStop (dtype, vs, stfnum=1):
+            typmap = {'down':'!8va(!', 'up':'!8vb(!', 'crescendo':'!<(!', 'diminuendo':'!>(!', 'start':'!ped!'}
+            type = t.get ('type', '')
+            k = dtype + t.get ('number', '1')       # key to match the closing direction
+            if type in typmap:                      # opening the direction
+                x = typmap [type]
+                if k in s.dirStk:                   # closing direction already encountered
+                    stype, tijd = s.dirStk [k]; del s.dirStk [k]
+                    if stype == 'stop':
+                        addDirection (x, vs, tijd, stfnum)
+                    else:
+                        info ('%s direction %s has no stop in part %d, measure %d, voice %d' % (dtype, stype, s.msr.ixp+1, s.msr.ixm+1, vs+1))
+                        s.dirStk [k] = ((type , vs))    # remember voice and type for closing
+                else:
+                    s.dirStk [k] = ((type , vs))    # remember voice and type for closing
+            elif type == 'stop':
+                if k in s.dirStk:                   # matching open direction found
+                    type, vs = s.dirStk [k]; del s.dirStk [k]   # into the same voice
+                    if type == 'stop':
+                        info ('%s direction %s has double stop in part %d, measure %d, voice %d' % (dtype, type, s.msr.ixp+1, s.msr.ixm+1, vs+1))
+                        x = ''
+                    else:
+                        x = typmap [type].replace ('(',')').replace ('ped','ped-up')
+                else:                               # closing direction found before opening
+                    s.dirStk [k] = ('stop', s.msc.tijd)
+                    x = ''                          # delay code generation until opening found
+            elif type in ['continue', 'resume', 'discontinue', 'change']:
+                # ?? 'continue' ? 'resume'????????????????
+                # ??????????????
+                # info('Ignoring unsupported direction type: %s' % type)
+                x = ''
+            else: raise ValueError ('wrong direction type')
+            addDirection (x, vs, None, stfnum)
+        tempo, wrdstxt = None, ''
+        plcmnt = e.get ('placement')
+        stf, vs, v1 = s.findVoice (i, es)
+        jmp = ''    # for jump sound elements: dacapo, dalsegno and family
+        jmps = [('dacapo','D.C.'),('dalsegno','D.S.'),('tocoda','dacoda'),('fine','fine'),('coda','O'),('segno','S')]
+        t = e.find ('sound')        # there are many possible attributes for sound
+        if t != None:
+            minst = t.find ('midi-instrument')
+            if minst:
+                prg = t.findtext ('midi-instrument/midi-program')
+                chn = t.findtext ('midi-instrument/midi-channel')
+                vids = [v for v, id in s.vceInst.items () if id == minst.get ('id')]
+                if vids: vs = vids [0]          # direction for the indentified voice, not the staff
+                parm, inst = ('program', str (int (prg) - 1)) if prg else ('channel', chn)
+                if inst and abcOut.volpan > 0: s.msc.appendElem (vs, '[I:MIDI= %s %s]' % (parm, inst))
+            tempo = t.get ('tempo') # look for tempo attribute
+            if tempo:
+                tempo = '%.0f' % float (tempo) # hope it is a number and insert in voice 1
+                tempo_units = (1,4) # always 1/4 for sound elements!
+            for r, v in jmps:
+                if t.get (r, ''): jmp = v; break
+        dirtypes = e.findall ('direction-type')
+        for dirtyp in dirtypes:
+            units = { 'whole': (1,1), 'half': (1,2), 'quarter': (1,4), 'eighth': (1,8) }
+            metr = dirtyp.find ('metronome')
+            if metr != None:
+                t = metr.findtext ('beat-unit', '')
+                if t in units:  tempo_units = units [t]
+                else:           tempo_units = units ['quarter']
+                if metr.find ('beat-unit-dot') != None:
+                    tempo_units = simplify (tempo_units [0] * 3, tempo_units [1] * 2)
+
+                debugtext = metr.findtext ('per-minute')
+                tmpro = None
+                if metr.findtext ('per-minute'):
+                    tmpro = re.search ('[.\d]+', metr.findtext ('per-minute'))  # look for a number #####
+                if tmpro: tempo = tmpro.group () # overwrites the value set by the sound element of this direction
+            t = dirtyp.find ('wedge')
+            if t != None: startStop ('wedge', vs)
+            allwrds = dirtyp.findall ('words')        # insert text annotations
+            if not allwrds: allwrds = dirtyp.findall ('rehearsal')   # treat rehearsal mark as text annotation
+            for wrds in allwrds:
+                if jmp: # ignore the words when a jump sound element is present in this direction
+                    s.msc.appendElem (vs, '!%s!' % jmp , 1) # to voice
+                    break
+                plc = plcmnt == 'below' and '_' or '^'
+                if float (wrds.get ('default-y', '0')) < 0: plc = '_'
+                wrdstxt += (wrds.text or '').replace ('"','\\"').replace ('\n', '\\n')
+            wrdstxt = wrdstxt.strip ()
+            for key, val in dynamics_map.items ():
+                if dirtyp.find ('dynamics/' + key) != None:
+                    s.msc.appendElem (vs, val, 1)   # to voice
+            if dirtyp.find ('coda') != None: s.msc.appendElem (vs, 'O', 1)
+            if dirtyp.find ('segno') != None: s.msc.appendElem (vs, 'S', 1)
+            t = dirtyp.find ('octave-shift')
+            if t != None: startStop ('octave-shift', vs, stf)   # assume size == 8 for the time being
+            t = dirtyp.find ('pedal')
+            if t != None and s.ped:
+                if not s.pedVce: s.pedVce = vs
+                startStop ('pedal', s.pedVce)
+            if dirtyp.findtext ('other-direction') == 'diatonic fretting': s.diafret = 1;
+        if tempo:
+            tempo = '%.0f' % float (tempo) # hope it is a number and insert in voice 1
+            if s.msc.tijd == 0 and s.msr.ixm == 0:      # first measure -> header
+                abcOut.tempo = tempo
+                abcOut.tempo_units = tempo_units
+            else:
+                s.msc.appendElem (v1, '[Q:%d/%d=%s]' % (tempo_units [0], tempo_units [1], tempo))   # otherwise -> 1st voice
+        if wrdstxt: s.msc.appendElem (vs, '"%s%s"' % (plc, wrdstxt), 1) # to voice, but after tempo
+
+    def doHarmony (s, e, i, es):    # parse a musicXMl harmony tag
+        _, vt, _ = s.findVoice (i, es)
+        short = {'major':'', 'minor':'m', 'augmented':'+', 'diminished':'dim', 'dominant':'7', 'half-diminished':'m7b5'}
+        accmap = {'major':'maj', 'dominant':'', 'minor':'m', 'diminished':'dim', 'augmented':'+', 'suspended':'sus'}
+        modmap = {'second':'2', 'fourth':'4', 'seventh':'7', 'sixth':'6', 'ninth':'9', '11th':'11', '13th':'13'}
+        altmap = {'1':'#', '0':'', '-1':'b'}
+        root = e.findtext ('root/root-step','')
+        alt = altmap.get (e.findtext ('root/root-alter'), '')
+        sus = ''
+        kind = e.findtext ('kind', '')
+        if kind in short: kind = short [kind]
+        elif '-' in kind:   # xml chord names: <triad name>-<modification>
+            triad, mod = kind.split ('-')
+            kind = accmap.get (triad, '') + modmap.get (mod, '')
+            if kind.startswith ('sus'): kind, sus = '', kind    # sus-suffix goes to the end
+        elif kind == 'none': kind = e.find ('kind').get ('text','')
+        degrees = e.findall ('degree')
+        for d in degrees:   # chord alterations
+            kind += altmap.get (d.findtext ('degree-alter'),'') + d.findtext ('degree-value','')
+        kind = kind.replace ('79','9').replace ('713','13').replace ('maj6','6')
+        bass = e.findtext ('bass/bass-step','') + altmap.get (e.findtext ('bass/bass-alter'),'') 
+        s.msc.appendElem (vt, '"%s%s%s%s%s"' % (root, alt, kind, sus, bass and '/' + bass), 1)
+
+    def doBarline (s, e):       # 0 = no repeat, 1 = begin repeat, 2 = end repeat
+        rep = e.find ('repeat')
+        if rep != None: rep = rep.get ('direction')
+        if s.unfold:            # unfold repeat, don't translate barlines
+            return rep and (rep == 'forward' and 1 or 2) or 0
+        loc = e.get ('location', 'right')   # right is the default
+        if loc == 'right':      # only change style for the right side
+            style = e.findtext ('bar-style')
+            if   style == 'light-light': s.msr.rline = '||'
+            elif style == 'light-heavy': s.msr.rline = '|]'
+        if rep != None:         # repeat found
+            if rep == 'forward': s.msr.lline = ':'
+            else:                s.msr.rline = ':|' # override barline style
+        end = e.find ('ending')
+        if end != None:
+            if end.get ('type') == 'start':
+                n = end.get ('number', '1').replace ('.','').replace (' ','')
+                try: list (map (int, n.split (',')))    # should be a list of integers
+                except: n = '"%s"' % n.strip ()         # illegal musicXML
+                s.msr.lnum = n          # assume a start is always at the beginning of a measure
+            elif s.msr.rline == '|':    # stop and discontinue the same  in ABC ?
+                s.msr.rline = '||'      # to stop on a normal barline use || in ABC ?
+        return 0
+
+    def doPrint (s, e):     # print element, measure number -> insert a line break
+        if e.get ('new-system') == 'yes' or e.get ('new-page') == 'yes':
+            if not s.nolbrk: return '$'  # a line break
+
+    def doPartList (s, e):  # translate the start/stop-event-based xml-partlist into proper tree
+        for sp in e.findall ('part-list/score-part'):
+            midi = {}
+            for m in sp.findall ('midi-instrument'):
+                x = [m.findtext (p, s.midDflt [i]) for i,p in enumerate (['midi-channel','midi-program','volume','pan'])]
+                pan = float (x[3])
+                if pan >= -90 and pan <= 90:    # would be better to map behind-pannings
+                    pan = (float (x[3]) + 90) / 180 * 127   # xml between -90 and +90
+                midi [m.get ('id')] = [int (x[0]), int (x[1]), float (x[2]) * 1.27, pan]    # volume 100 -> midi 127
+                up = m.findtext ('midi-unpitched')
+                if up: s.drumInst [m.get ('id')] = int (up) - 1 # store midi-pitch for channel 10 notes
+            s.instMid.append (midi)
+        ps = e.find ('part-list')               # partlist  = [groupelem]
+        xs = getPartlist (ps)                   # groupelem = partname | grouplist
+        partlist, _ = parseParts (xs, {}, [])   # grouplist = [groupelem, ..., groupdata]
+        return partlist                         # groupdata = [group-symbol, group-barline, group-name, group-abbrev]
+
+    def mkTitle (s, e):
+        def filterCredits (y):  # y == filter level, higher filters less
+            cs = []
+            for x in credits:   # skip redundant credit lines
+                if y < 6 and (x in title or x in mvttl): continue         # sure skip
+                if y < 5 and (x in composer or x in lyricist): continue   # almost sure skip
+                if y < 4 and ((title and title in x) or (mvttl and mvttl in x)): continue   # may skip too much
+                if y < 3 and ([1 for c in composer if c in x] or [1 for c in lyricist if c in x]): continue # skips too much
+                if y < 2 and re.match (r'^[\d\W]*$', x): continue       # line only contains numbers and punctuation
+                cs.append (x)
+            if y == 0 and (title + mvttl): cs = ''  # default: only credit when no title set
+            return cs
+        title = e.findtext ('work/work-title', '').strip ()
+        mvttl = e.findtext ('movement-title', '').strip ()
+        composer, lyricist, credits = [], [], []
+        for creator in e.findall ('identification/creator'):
+            if creator.text:
+                if creator.get ('type') == 'composer':
+                    composer += [line.strip () for line in creator.text.split ('\n')]
+                elif creator.get ('type') in ('lyricist', 'transcriber'):
+                    lyricist += [line.strip () for line in creator.text.split ('\n')]
+        for rights in e.findall ('identification/rights'):
+            if rights.text:
+                lyricist += [line.strip () for line in rights.text.split ('\n')]
+        for credit in e.findall('credit'):
+            cs = ''.join (e.text or '' for e in credit.findall('credit-words'))
+            credits += [re.sub (r'\s*[\r\n]\s*', ' ', cs)]
+        credits = filterCredits (s.ctf)
+        if title: title = 'T:%s\n' % title.replace ('\n', '\nT:')
+        if mvttl: title += 'T:%s\n' % mvttl.replace ('\n', '\nT:')
+        if credits: title += '\n'.join (['T:%s' % c for c in credits]) + '\n'
+        if composer: title += '\n'.join (['C:%s' % c for c in composer]) + '\n'
+        if lyricist: title += '\n'.join (['Z:%s' % c for c in lyricist]) + '\n'
+        if title: abcOut.title = title[:-1]
+        s.isSib = 'Sibelius' in (e.findtext ('identification/encoding/software') or '')
+        if s.isSib: info ('Sibelius MusicXMl is unreliable')
+
+    def doDefaults (s, e):
+        if not s.doPageFmt: return  # return if -pf option absent
+        d = e.find ('defaults');
+        if d == None: return;
+        mils = d.findtext ('scaling/millimeters')   # mills == staff height (mm)
+        tenths = d.findtext ('scaling/tenths')      # staff height in tenths
+        if not mils or not tenths: return
+        xmlScale = float (mils) / float (tenths) / 10   # tenths -> mm
+        space = 10 * xmlScale       # space between staff lines == 10 tenths
+        abcScale = space / 0.2117   # 0.2117 cm = 6pt = space between staff lines for scale = 1.0 in abcm2ps
+        abcOut.pageFmt ['scale'] = abcScale
+        eks = 2 * ['page-layout/'] + 4 * ['page-layout/page-margins/']
+        eks = [a+b for a,b in zip (eks, 'page-height,page-width,left-margin,right-margin,top-margin,bottom-margin'.split (','))]
+        for i in range (6):
+            v = d.findtext (eks [i])
+            k = abcOut.pagekeys [i+1]   # pagekeys [0] == scale already done, skip it
+            if not abcOut.pageFmt [k] and v:
+                try: abcOut.pageFmt [k] = float (v) * xmlScale  # -> cm
+                except: info ('illegal value %s for xml element %s', (v, eks [i])); continue    # just skip illegal values
+
+    def locStaffMap (s, part, maten):   # map voice to staff with majority voting
+        vmap = {}   # {voice -> {staff -> n}} count occurrences of voice in staff
+        s.vceInst = {}          # {voice -> instrument id} for this part
+        s.msc.vnums = {}        # voice id's
+        s.hasStems = {}         # XML voice nums with at least one note with a stem (for tab key)
+        s.stfMap, s.clefMap = {}, {}    # staff -> [voices], staff -> clef
+        ns = part.findall ('measure/note')
+        for n in ns:            # count staff allocations for all notes
+            v = int (n.findtext ('voice', '1'))
+            if s.isSib: v += 100 * int (n.findtext ('staff', '1'))  # repair bug in Sibelius
+            s.msc.vnums [v] = 1 # collect all used voice id's in this part
+            sn = int (n.findtext ('staff', '1'))
+            s.stfMap [sn] = []
+            if v not in vmap:
+                vmap [v] = {sn:1}
+            else:
+                d = vmap[v]     # counter for voice v
+                d[sn] = d.get (sn, 0) + 1   # ++ number of allocations for staff sn
+            x = n.find ('instrument')
+            if x != None: s.vceInst [v] = x.get ('id')
+            x, noRest = n.findtext ('stem'), n.find ('rest') == None
+            if noRest and (not x or x != 'none'): s.hasStems [v] = 1    # XML voice v has at least one stem
+        vks = list (vmap.keys ())
+        if s.jscript or s.isSib: vks.sort ()
+        for v in vks:           # choose staff with most allocations for each voice
+            xs = [(n, sn) for sn, n in vmap[v].items ()]
+            xs.sort ()
+            stf = xs[-1][1]     # the winner: staff with most notes of voice v
+            s.stfMap [stf].append (v)
+            s.vce2stf [v] = stf # reverse map
+            s.curStf [v] = stf  # current staff of XML voice v
+
+    def addStaffMap (s, vvmap): # vvmap: xml voice number -> global abc voice number
+        part = [] # default: brace on staffs of one part
+        for stf, voices in sorted (s.stfMap.items ()):  # s.stfMap has xml staff and voice numbers
+            locmap = [vvmap [iv] for iv in voices if iv in vvmap]
+            nostem = [(iv not in s.hasStems) for iv in voices if iv in vvmap]   # same order as locmap
+            if locmap:          # abc voice number of staff stf
+                part.append (locmap)
+                clef = s.clefMap.get (stf, 'treble')    # {xml staff number -> clef}
+                for i, iv in enumerate (locmap):
+                    clef_attr = ''
+                    if clef.startswith ('tab'):
+                        if nostem [i] and 'nostems' not in clef: clef_attr = ' nostems'
+                        if s.diafret and 'diafret' not in clef: clef_attr += ' diafret' # for all voices in the part
+                    abcOut.clefs [iv] = clef + clef_attr # add nostems when all notes of voice had no stem
+        s.gStfMap.append (part)
+
+    def addMidiMap (s, ip, vvmap):      # map abc voices to midi settings
+        instr = s.instMid [ip]          # get the midi settings for this part
+        if instr.values (): defInstr = list(instr.values ())[0]   # default settings = first instrument
+        else:               defInstr = s.midDflt    # no instruments defined
+        xs = []
+        for v, vabc in vvmap.items ():  # xml voice num, abc voice num
+            ks = sorted (s.drumNotes.items ())
+            ds = [(nt, step, midi, head) for (vd, nt), (step, midi, head) in ks if v == vd] # map perc notes
+            id = s.vceInst.get (v, '')  # get the instrument-id for part with multiple instruments
+            if id in instr:             # id is defined as midi-instrument in part-list
+                   xs.append ((vabc, instr [id] + ds))  # get midi settings for id 
+            else:  xs.append ((vabc, defInstr   + ds))  # only one instrument for this part
+        xs.sort ()  # put abc voices in order
+        s.midiMap.extend ([midi for v, midi in xs])
+        snaarmap = ['E','G','B','d', 'f', 'a', "c'", "e'"]
+        diamap = '0,1-,1,1+,2,3,3,4,4,5,6,6+,7,8-,8,8+,9,10,10,11,11,12,13,13+,14'.split (',')
+        for k in sorted (s.tabmap.keys ()): # add %%map's for all tab voices
+            v, noot = k;
+            snaar, fret = s.tabmap [k];
+            if s.diafret: fret = diamap [int (fret)]
+            vabc = vvmap [v]
+            snaar = s.stafflines - int (snaar)
+            xs = s.tabVceMap.get (vabc, [])
+            xs.append ('%%%%map tab%d %s print=%s heads=kop%s\n' % (vabc, noot, snaarmap [snaar], fret))
+            s.tabVceMap [vabc] = xs
+            s.koppen [fret] = 1  # collect noteheads for SVG defs
+
+    def parse (s, fobj):
+        vvmapAll = {}   # collect xml->abc voice maps (vvmap) of all parts
+        e = E.parse (fobj)
+        s.mkTitle (e)
+        s.doDefaults (e)
+        partlist = s.doPartList (e)
+        parts = e.findall ('part')
+        for ip, p in enumerate (parts):
+            maten = p.findall ('measure')
+            s.locStaffMap (p, maten)        # {voice -> staff} for this part
+            s.drumNotes = {}    # (xml voice, abc note) -> (midi note, note head)
+            s.clefOct = {}      # xml staff number -> current clef-octave-change
+            s.curClef = {}      # xml staff number -> current abc clef
+            s.stemDir = {}      # xml voice number -> current stem direction
+            s.tabmap = {}       # (xml voice, abc note) -> (string, fret)
+            s.diafret = 0       # use diatonic fretting
+            s.stafflines = 5
+            s.msc.initVoices (newPart = 1)  # create all voices
+            aantalHerhaald = 0  # keep track of number of repititions
+            herhaalMaat = 0     # target measure of the repitition
+            divisions = []      # current value of <divisions> for each measure
+            s.msr = Measure (ip)   # various measure data
+            while s.msr.ixm < len (maten):
+                if ip == 31 and s.msr.ixm == 405:
+                    print('')
+                maat = maten [s.msr.ixm]
+                herhaal, lbrk = 0, ''
+                s.msr.reset ()
+                s.curalts = {}  # passing accidentals are reset each measure
+                es = list (maat)
+                for i, e in enumerate (es):
+                    if   e.tag == 'note':       s.doNote (e)
+                    elif e.tag == 'attributes': s.doAttr (e)
+                    elif e.tag == 'direction':
+                        s.doDirection (e, i, es)
+                    elif e.tag == 'sound':      s.doDirection (maat, i, es) # sound element directly in measure!
+                    elif e.tag == 'harmony':    s.doHarmony (e, i, es)
+                    elif e.tag == 'barline':
+                        herhaal = s.doBarline (e)
+                    elif e.tag == 'backup':
+                        dt = int (e.findtext ('duration'))
+                        if chkbug (dt, s.msr): s.msc.incTime (-dt)
+                    elif e.tag == 'forward':
+                        dt = int (e.findtext ('duration'))
+                        if chkbug (dt, s.msr): s.msc.incTime (dt)
+                    elif e.tag == 'print':  lbrk = s.doPrint (e)
+                s.msc.addBar (lbrk, s.msr)
+                divisions.append (s.msr.divs)
+                if herhaal == 1:
+                    herhaalMaat = s.msr.ixm
+                    s.msr.ixm += 1
+                elif herhaal == 2:
+                    if aantalHerhaald < 1:  # jump
+                        s.msr.ixm = herhaalMaat
+                        aantalHerhaald += 1
+                    else:
+                        aantalHerhaald = 0  # reset
+                        s.msr.ixm += 1      # just continue
+                else: s.msr.ixm += 1        # on to the next measure
+            for rv in s.repeat_str.values ():   # close hanging measure-repeats without stop
+                rv [0] = '[I:repeat %s %d]' % (rv [1], 1)
+            vvmap = s.msc.outVoices (divisions, ip, s.isSib)
+            s.addStaffMap (vvmap)           # update global staff map
+            s.addMidiMap (ip, vvmap)
+            vvmapAll.update (vvmap)
+        if vvmapAll:            # skip output if no part has any notes
+            abcOut.mkHeader (s.gStfMap, partlist, s.midiMap, s.tabVceMap, s.koppen)
+            abcOut.writeall ()
+        else: info ('nothing written, %s has no notes ...' % abcOut.fnmext)
+
+#----------------
+# Main Program
+#----------------
+if __name__ == '__main__':
+    from optparse import OptionParser
+    from glob import glob
+    from zipfile import ZipFile 
+    ustr = '%prog [-h] [-u] [-m] [-c C] [-d D] [-n CPL] [-b BPL] [-o DIR] [-v V]\n'
+    ustr += '[-x] [-p PFMT] [-t] [-s] [-i] [--v1] [--noped] [--stems] <file1> [<file2> ...]'
+    parser = OptionParser (usage=ustr, version=str(VERSION))
+    parser.add_option ("-u", action="store_true", help="unfold simple repeats")
+    parser.add_option ("-m", action="store", help="0 -> no %%MIDI, 1 -> minimal %%MIDI, 2-> all %%MIDI", default=0)
+    parser.add_option ("-c", action="store", type="int", help="set credit text filter to C", default=0, metavar='C')
+    parser.add_option ("-d", action="store", type="int", help="set L:1/D", default=0, metavar='D')  # ??????????????L
+    parser.add_option ("-n", action="store", type="int", help="CPL: max number of characters per line (default 100)", default=0, metavar='CPL')
+    parser.add_option ("-b", action="store", type="int", help="BPL: max number of bars per line", default=0, metavar='BPL')
+    parser.add_option ("-o", action="store", help="store abc files in DIR", default='', metavar='DIR')
+    parser.add_option ("-v", action="store", type="int", help="set volta typesetting behaviour to V", default=0, metavar='V')
+    parser.add_option ("-x", action="store_true", help="output no line breaks")
+    parser.add_option ("-p", action="store", help="pageformat PFMT (cm) = scale, pageheight, pagewidth, leftmargin, rightmargin, topmargin, botmargin", default='', metavar='PFMT')
+    parser.add_option ("-j", action="store_true", help="switch for compatibility with javascript version")
+    parser.add_option ("-t", action="store_true", help="translate perc- and tab-staff to ABC code with %%map, %%voicemap")
+    parser.add_option ("-s", action="store_true", help="shift node heads 3 units left in a tab staff")
+    parser.add_option ("--v1", action="store_true", help="start-stop directions allways to first voice of staff")
+    parser.add_option ("--noped", action="store_false", help="skip all pedal directions", dest='ped', default=True)
+    parser.add_option ("--stems", action="store_true", help="translate stem directions", dest='stm', default=False)
+    parser.add_option ("-i", action="store_true", help="read xml file from standard input")
+    options, args = parser.parse_args ()
+    if options.n < 0: parser.error ('only values >= 0')
+    if options.b < 0: parser.error ('only values >= 0')
+    if options.d and options.d not in [2**n for n in range (10)]:
+        parser.error ('D should be on of %s' % ','.join ([str(2**n) for n in range (10)]))
+    options.p = options.p and options.p.split (',') or [] # ==> [] | [string]
+    if len (args) == 0 and not options.i: parser.error ('no input file given')
+    pad = options.o
+    if pad:
+        if not os.path.exists (pad): os.mkdir (pad)
+        if not os.path.isdir (pad): parser.error ('%s is not a directory' % pad)
+    fnmext_list = []
+    for i in args: fnmext_list += glob (i)
+    if options.i: fnmext_list = ['stdin.xml']
+    if not fnmext_list: parser.error ('none of the input files exist')
+    for X, fnmext in enumerate (fnmext_list):
+        fnm, ext = os.path.splitext (fnmext)
+        if ext.lower () not in ('.xml','.mxl','.musicxml'):
+            info ('skipped input file %s, it should have extension .xml or .mxl' % fnmext)
+            continue
+        if os.path.isdir (fnmext):
+            info ('skipped directory %s. Only files are accepted' % fnmext)
+            continue
+        if fnmext == 'stdin.xml':
+            fobj = sys.stdin
+        elif ext.lower () == '.mxl':        # extract .xml file from .mxl file
+            z = ZipFile(fnmext)
+            for n in z.namelist():          # assume there is always an xml file in a mxl archive !!
+                if (n[:4] != 'META') and (n[-4:].lower() == '.xml'):
+                    fobj = z.open (n)
+                    break   # assume only one MusicXML file per archive
+        else:
+            fobj = open (fnmext, 'rb')      # open regular xml file
+
+        abcOut = ABCoutput (fnm + '.abc', pad, X, options)  # create global ABC output object
+        psr = Parser (options)  # xml parser
+        try:
+            psr.parse (fobj)    # parse file fobj and write abc to <fnm>.abc
+        except:
+            etype, value, traceback = sys.exc_info ()   # works in python 2 & 3
+            info ('** %s occurred: %s in %s' % (etype, value, fnmext), 0)