import torch import torch as t import html import json import math import re import io import base64 import numpy as np import matplotlib.pyplot as plt from PIL import Image from typing import Any, Dict, List, Tuple, OrderedDict, Optional from torch import Tensor import torch.nn.functional as F from torchvision.utils import make_grid from torch.utils.data import Dataset # --------------------------------------------------------- # 1. HTML / Viz Helpers # --------------------------------------------------------- def _render_token_html(tokens: List[str], acts: List[float], target_idx: int, max_global: float) -> str: html_str = "" for i, (tok, act) in enumerate(zip(tokens, acts)): ratio = act / max_global if max_global > 0 else 0 alpha = max(0.0, min(1.0, ratio)) bg_color = f"rgba(0, 200, 83, {alpha})" if act > 0 else "transparent" # Handle special chars safe_tok = html.escape(tok).replace('\n', '↵') is_target = (i == target_idx) target_class = "target-token" if is_target else "" html_str += f'{safe_tok}{act:.4f}' return html_str def generate_interactive_html_embeddable(data: Dict[str, Any]) -> str: css_content = """""" html_content = f"""
{css_content}
Max Act: {data['max_act']:.4f}
""" max_global = data['max_act'] for interval in data['intervals']: density_pct = interval['density'] * 100 html_content += f"""
{interval['min']:.2f}-{interval['max']:.2f}{density_pct:.5f}%
""" for ex in interval['examples']: short_html = _render_token_html(ex['short']['tokens'], ex['short']['activations'], ex['short']['target_idx'], max_global) full_html = _render_token_html(ex['full']['tokens'], ex['full']['activations'], ex['full']['target_idx'], max_global) html_content += f"""
{ex['target_act']:.2f}
{short_html}
""" html_content += "
" html_content += "
" return html_content # --------------------------------------------------------- # 2. Vision Processing Helpers # --------------------------------------------------------- def check_vision_sae(hook_name: str) -> bool: """Detects if a hook belongs to the vision component of BLIP.""" return "visual" in hook_name or "vision" in hook_name def denorm(img_tensor): mean = torch.tensor([0.485, 0.456, 0.406]).view(3,1,1) std = torch.tensor([0.229, 0.224, 0.225]).view(3,1,1) # Ensure inputs are on the same device mean = mean.to(img_tensor.device) std = std.to(img_tensor.device) return (img_tensor * std + mean).clamp(0, 1) def generate_base64_image_html(feat_idx: int, values: Tensor, indices: Tensor, dataset: Dataset, top_k: int = 10) -> str: """ Generates a Base64 string of the combined heatmap visualization for a vision feature. Returns an HTML tag. """ if dataset is None: return "
No dataset provided for vision viz.
" mask = (values > 1e-3) * (indices == feat_idx) if mask.sum() == 0: return "
No significant vision activation found.
" filtered_values = values * mask.to(values.dtype) # (b, activated_dim) sumed_filtered_values = filtered_values.sum(dim=1) # (b) top_vals, top_indices = sumed_filtered_values.topk(k=top_k) # (topk) top_acts = filtered_values[top_indices, :] # (topk, activated_dim) crops = [] try: for each in range(top_indices.shape[0]): item = dataset[top_indices[each].item()] # Handle different dataset return formats, assuming 'pixel_values' is a tensor if isinstance(item, dict) and 'pixel_values' in item: crops.append(item['pixel_values']) else: # Fallback if dataset returns tuple crops.append(item[0]) except Exception as e: return f"
Error accessing dataset: {str(e)}
" if not crops: return "
No crops extracted
" crops_tensor = torch.stack(crops, dim=0) # [top_k, 3, 384, 384] # 1. Standard Grid grid = make_grid(denorm(crops_tensor), nrow=5, padding=12, pad_value=1.0) grid = (grid.clamp(0,1) * 255).byte().cpu().permute(1,2,0).numpy() grid_pil = Image.fromarray(grid) # # 2. Heatmap Overlay # overlaid_crops = [] # for each in range(crops_tensor.shape[0]): # img = denorm(crops_tensor[each]).permute(1,2,0).cpu().numpy() # [384,384,3] # act_flat = top_acts[each] # [576] # # Assume square feature map. sqrt(576) = 24 # side = int(math.sqrt(act_flat.shape[0])) # act_map = act_flat.view(side, side) # # Normalize per image # act_map = (act_map - act_map.min()) / (act_map.max() - act_map.min() + 1e-8) # # Upsample to image size # act_up = F.interpolate( # act_map.unsqueeze(0).unsqueeze(0), # size=(img.shape[0], img.shape[1]), # mode='bilinear', # align_corners=False # )[0][0] # act_np = act_up.numpy() # # Apply colormap # heat_rgba = plt.cm.jet(act_np) # heat_rgb = heat_rgba[:,:,:3] # alpha = 0.4 # overlaid = img * (1 - alpha) + heat_rgb * alpha # overlaid = overlaid.clip(0, 1) # overlaid_tensor = torch.from_numpy(overlaid).float().permute(2,0,1) # overlaid_crops.append(overlaid_tensor) # overlaid_tensor_stack = torch.stack(overlaid_crops, dim=0) # overlay_grid = make_grid(overlaid_tensor_stack, nrow=5, padding=12, pad_value=1.0) # overlay_grid = (overlay_grid.clamp(0,1) * 255).byte().cpu().permute(1,2,0).numpy() # overlay_grid_pil = Image.fromarray(overlay_grid) # # 3. Combine # width = grid_pil.width + overlay_grid_pil.width # height = max(grid_pil.height, overlay_grid_pil.height) # combined = Image.new('RGB', (width, height), (255, 255, 255)) # combined.paste(grid_pil, (0, 0)) # combined.paste(overlay_grid_pil, (grid_pil.width, 0)) # 4. To Base64 buffered = io.BytesIO() grid_pil.save(buffered, format="JPEG", quality=85) img_str = base64.b64encode(buffered.getvalue()).decode("utf-8") return f'' # --------------------------------------------------------- # 3. Main Logic # --------------------------------------------------------- class SAEGraphVisualizer: def __init__(self, graph_obj, model, processor, sae_dict, tokens, full_data_dict=None, data_toks=None, dataset=None): """ Args: graph_obj: The sparse feature graph. model: The Blip model object processor: BlipProcessor (or similar) containing .tokenizer. sae_dict: Dictionary containing SAE-related utilities. tokens: List of token IDs or Tensor of token IDs. full_data_dict: Dictionary for retrieving activation data (keys: hook_name). data_toks: Tokens corresponding to the full_data_dict dataset (for text intervals). dataset: The PyTorch dataset object used for retrieving images (required for vision nodes). """ self.graph = graph_obj self.model = model self.processor = processor self.sae_dict = sae_dict self.full_data_dict = full_data_dict self.data_toks = data_toks self.dataset = dataset # Handle tensor or list input for tokens if hasattr(tokens, 'tolist'): token_ids = tokens.tolist() else: token_ids = tokens self.tokens = [processor.tokenizer.decode(t) for t in token_ids] self.prompt_str = "".join(self.tokens) def get_layer_fallback(self, hook_name: str) -> int: match = re.search(r'\.(\d+)\.', hook_name) return int(match.group(1)) if match else 0 def get_component_order(self, hook_name: str, layer: int) -> int: # Standardize component positioning for visual layout if "resid" in hook_name: return 0 if "attn" in hook_name: return 1 if "mlp" in hook_name: return 2 if "vision" in hook_name: return 3 # Vision components usually processed before text or parallel return 0 def get_logits_html(self, hook_name, feat_idx): if self.model is None: return "Model not provided" try: sae = self.sae_dict.get(hook_name) if not sae: return "N/A" # Extract feature vector if hasattr(sae, 'W_dec'): vec = sae.W_dec[feat_idx] elif hasattr(sae, 'decoder'): vec = sae.decoder.weight.data.T[feat_idx] else: return "N/A" # Ensure vec is on model device vec = vec.to(self.model.device) # Projection (BLIP specific modification) # Logits = model.text_decoder.cls.forward(vec) logits = self.model.text_decoder.cls(vec) k = 5 pos_vals, pos_ids = logits.topk(k) neg_vals, neg_ids = logits.topk(k, largest=False) def pill(t_str, v, top): c = "background:#d4edda;color:#155724" if top else "background:#f8d7da;color:#721c24" return f'{html.escape(t_str)}' h = "
Top
" for idx, v in zip(pos_ids, pos_vals): # Use processor tokenizer for decoding t_str = self.processor.tokenizer.decode([idx]).replace('\n', '↵') h += pill(t_str, v.item(), True) h += "
Bottom
" for idx, v in zip(neg_ids, neg_vals): t_str = self.processor.tokenizer.decode([idx]).replace('\n', '↵') h += pill(t_str, v.item(), False) h += "
" return h except Exception as e: return f"Error: {str(e)}" def get_activation_html(self, hook_name, feat_idx, seq_pos): # Only use this for TEXT nodes if check_vision_sae(hook_name): return "
Vision node activation
" if self.data_toks is not None and self.full_data_dict and hook_name in self.full_data_dict: values, indices = self.full_data_dict[hook_name] try: # Call the Blip-specific interval fetcher # Assuming 'fetch_feature_activation_intervals_blip' is imported or available in context # If not, we fall back to a generic one or assume it exists in `sae.SAE_Blip_Explaining_Utils` from sae.SAE_Blip_Explaining_Utils import fetch_feature_activation_intervals_blip data = fetch_feature_activation_intervals_blip(self.processor, feat_idx, values, indices, self.data_toks, 5, 5, 10) return generate_interactive_html_embeddable(data) except ImportError: return "
fetch_feature_activation_intervals_blip not found
" except Exception as e: return f"
Error: {str(e)}
" return "
No activation data.
" def get_vision_node_html(self, hook_name, feat_idx): """ Generates the visual inspection HTML (crops + heatmaps) for a vision node. """ if self.full_data_dict and hook_name in self.full_data_dict: values, indices = self.full_data_dict[hook_name] return generate_base64_image_html(feat_idx, values.float(), indices.float(), self.dataset, top_k=5) # type: ignore return "
No vision data available in full_data_dict
" def build_graph_json(self): nodes_list = [] raw_links_list = [] # OPTIMIZATION 1: Pre-compute layer mapping to avoid O(N*L) lookups hook_to_layer = {} for cur_layer, dict_connection in self.graph.connection.items(): for (k, _) in dict_connection.keys(): hook_to_layer[k.name] = cur_layer # 1. Collect valid nodes and Vision Requests first valid_text_ids = set() valid_vision_ids = set() vision_feat_set = set() # (hook, feat_idx) for HTML generation # OPTIMIZATION 2: Cache for text feature HTML to avoid redundant dataset fetches # Map: (hook_name, feat_idx) -> html_string text_act_html_cache = {} text_logits_cache = {} def get_id(hook, seq, feat, is_err): prefix = "vis" if check_vision_sae(hook) else "txt" return f"{prefix}::{hook}::{seq}::{'err' if is_err else 'feat'}::{feat}" # Loop Nodes for (node_key, _), sparse_act in self.graph.nodes.items(): hook = node_key.name is_vision = check_vision_sae(hook) # Layer determination (O(1) lookup) layer = hook_to_layer.get(hook, -1) if layer == -1: layer = self.get_layer_fallback(hook) comp = self.get_component_order(hook, layer) scores = self.graph.node_scores.get((node_key, _)) def process_nodes(is_resc): tensor_data = sparse_act.resc if is_resc else sparse_act.act if tensor_data is None: return nz = tensor_data.nonzero(as_tuple=True) # UPDATED LOGIC: Handle 1D tensors (errors) vs 2D tensors (features) if len(nz) == 1: s_indices = nz[0] f_indices = -t.ones_like(s_indices) else: s_indices = nz[0] f_indices = nz[1] for s, f in zip(s_indices, f_indices): s_item, f_item = s.item(), f.item() score_val = 0.0 if scores: # Handle score indexing safely for 1D vs 2D if len(scores.act.shape) == 1: # If scores are 1D, they usually align with the 1D tensor data (e.g. error seq) idx = s_item if len(nz) == 1 else f_item score_val = scores.resc[idx].item() if is_resc else scores.act[idx].item() else: score_val = scores.resc[s_item].item() if is_resc else scores.act[s_item, f_item].item() node_id = get_id(hook, s_item, f_item if not is_resc else 0, is_resc) if is_vision: # For vision, we only track valid features if not is_resc and f_item != -1: valid_vision_ids.add(node_id) vision_feat_set.add((hook, f_item)) else: # For text, add to graph nodes immediately # OPTIMIZATION 2 Implementation: Check cache logits_html = "" act_html = "" if not is_resc: cache_key = (hook, f_item) if cache_key in text_act_html_cache: act_html = text_act_html_cache[cache_key] else: act_html = self.get_activation_html(hook, f_item, s_item) text_act_html_cache[cache_key] = act_html if cache_key in text_logits_cache: logits_html = text_logits_cache[cache_key] else: logits_html = self.get_logits_html(hook, f_item) text_logits_cache[cache_key] = logits_html valid_text_ids.add(node_id) nodes_list.append({ "id": node_id, "label": "Err" if is_resc else f"{f_item}", "type": "error" if is_resc else "feature", "layer": layer, "comp": comp, "seq": s_item, "score": score_val, "hook": hook, "feat_idx": -1 if is_resc else f_item, "act_html": act_html, "logits_html": logits_html, "vision_links": [] }) process_nodes(False) # Features process_nodes(True) # Errors # 2. Generate Vision HTML (Batch Process unique valid vision nodes) vision_html_map = {} for (v_hook, v_feat) in vision_feat_set: vision_html_map[(v_hook, v_feat)] = self.get_vision_node_html(v_hook, v_feat) # 3. Process Edges (Only considering VALID nodes) # Create map for fast access to text node objects to append vision links text_node_map = {n['id']: n for n in nodes_list} for (end_key, end_idx), start_dict in self.graph.edges.items(): end_hook = end_key.name end_is_vision = check_vision_sae(end_hook) for (start_key, start_idx), edge_tensor in start_dict.items(): start_hook = start_key.name start_is_vision = check_vision_sae(start_hook) indices = edge_tensor.coalesce().indices() values = self.graph.edge_scores[(end_key, end_idx)][(start_key, start_idx)].coalesce().values() d_start = values.shape[2] - 1 for i in range(indices.shape[1]): end_seq, end_feat = indices[0, i].item(), indices[1, i].item() src_nz = values[i].nonzero(as_tuple=True) for src_seq, src_feat in zip(*src_nz): src_seq, src_feat = src_seq.item(), src_feat.item() weight = values[i][src_seq, src_feat].item() is_err_src = (src_feat == d_start) src_real_feat = src_feat if not is_err_src else 0 src_id = get_id(start_hook, src_seq, src_real_feat, is_err_src) tgt_id = get_id(end_hook, end_seq, end_feat, False) # FILTER: Check if both nodes are valid src_valid = (src_id in valid_vision_ids) if start_is_vision else (src_id in valid_text_ids) tgt_valid = (tgt_id in valid_vision_ids) if end_is_vision else (tgt_id in valid_text_ids) if not src_valid or not tgt_valid: continue # Add Links # Case A: Text -> Text if not start_is_vision and not end_is_vision: raw_links_list.append({"source": src_id, "target": tgt_id, "value": weight}) # Case B: Vision -> Text (Input) elif start_is_vision and not end_is_vision: if tgt_id in text_node_map: html_content = vision_html_map.get((start_hook, src_real_feat), "
Error
") text_node_map[tgt_id]['vision_links'].append({ "id": src_id, "hook": start_hook, "feat": src_real_feat, "score": weight, "type": "feature", "image_html": html_content, "direction": "input" }) # Case C: Text -> Vision (Output) elif not start_is_vision and end_is_vision: if src_id in text_node_map: html_content = vision_html_map.get((end_hook, end_feat), "
Error
") text_node_map[src_id]['vision_links'].append({ "id": tgt_id, "hook": end_hook, "feat": end_feat, "score": weight, "type": "feature", "image_html": html_content, "direction": "output" }) # 4. Clean up and Merge # Sort vision links by score for better UI presentation for node in nodes_list: if node['vision_links']: node['vision_links'].sort(key=lambda x: abs(x['score']), reverse=True) max_comps = max((n['comp'] for n in nodes_list), default=0) + 1 max_node_score = max((abs(n['score']) for n in nodes_list), default=1.0) return { "nodes": nodes_list, "links": raw_links_list, # raw_links_list only contains valid connections now "prompt": self.prompt_str, "layers": sorted(list(set(n["layer"] for n in nodes_list))), "tokens": self.tokens, "max_comps": max(3, max_comps), "max_node_score": max_node_score } def generate_html(self, output_path="sae_graph_blip.html"): data = self.build_graph_json() class NaNEncoder(json.JSONEncoder): def default(self, o): return 0 if isinstance(o, float) and math.isnan(o) else super().default(o) json_data = json.dumps(data, cls=NaNEncoder) html_template = f""" BLIP SAE Circuit
Prompt: {self.prompt_str}
""" with open(output_path, "w", encoding="utf-8") as f: f.write(html_template) print(f"Visualization saved to {output_path}")