from transformers import CLIPImageProcessor from torch.utils.checkpoint import checkpoint from functools import partial from typing import Callable, Optional, Tuple, Union import torch import torch.nn as nn from timm.layers import trunc_normal_,AvgPool2dSame, DropPath, Mlp, GlobalResponseNormMlp, \ LayerNorm2d, LayerNorm, create_conv2d, get_act_layer, make_divisible, to_ntuple from timm.layers import NormMlpClassifierHead, ClassifierHead from timm.models._manipulate import named_apply, checkpoint_seq __all__ = ['ConvNeXt'] class Downsample(nn.Module): def __init__(self, in_chs, out_chs, stride=1, dilation=1): super().__init__() avg_stride = stride if dilation == 1 else 1 if stride > 1 or dilation > 1: avg_pool_fn = AvgPool2dSame if avg_stride == 1 and dilation > 1 else nn.AvgPool2d self.pool = avg_pool_fn(2, avg_stride, ceil_mode=True, count_include_pad=False) else: self.pool = nn.Identity() if in_chs != out_chs: self.conv = create_conv2d(in_chs, out_chs, 1, stride=1) else: self.conv = nn.Identity() def forward(self, x): x = self.pool(x) x = self.conv(x) return x class ConvNeXtBlock(nn.Module): """ ConvNeXt Block There are two equivalent implementations: (1) DwConv -> LayerNorm (channels_first) -> 1x1 Conv -> GELU -> 1x1 Conv; all in (N, C, H, W) (2) DwConv -> Permute to (N, H, W, C); LayerNorm (channels_last) -> Linear -> GELU -> Linear; Permute back Unlike the official impl, this one allows choice of 1 or 2, 1x1 conv can be faster with appropriate choice of LayerNorm impl, however as model size increases the tradeoffs appear to change and nn.Linear is a better choice. This was observed with PyTorch 1.10 on 3090 GPU, it could change over time & w/ different HW. """ def __init__( self, in_chs: int, out_chs: Optional[int] = None, kernel_size: int = 7, stride: int = 1, dilation: Union[int, Tuple[int, int]] = (1, 1), mlp_ratio: float = 4, conv_mlp: bool = False, conv_bias: bool = True, use_grn: bool = False, ls_init_value: Optional[float] = 1e-6, act_layer: Union[str, Callable] = 'gelu', norm_layer: Optional[Callable] = None, drop_path: float = 0., ): """ Args: in_chs: Block input channels. out_chs: Block output channels (same as in_chs if None). kernel_size: Depthwise convolution kernel size. stride: Stride of depthwise convolution. dilation: Tuple specifying input and output dilation of block. mlp_ratio: MLP expansion ratio. conv_mlp: Use 1x1 convolutions for MLP and a NCHW compatible norm layer if True. conv_bias: Apply bias for all convolution (linear) layers. use_grn: Use GlobalResponseNorm in MLP (from ConvNeXt-V2) ls_init_value: Layer-scale init values, layer-scale applied if not None. act_layer: Activation layer. norm_layer: Normalization layer (defaults to LN if not specified). drop_path: Stochastic depth probability. """ super().__init__() out_chs = out_chs or in_chs dilation = to_ntuple(2)(dilation) act_layer = get_act_layer(act_layer) if not norm_layer: norm_layer = LayerNorm2d if conv_mlp else LayerNorm mlp_layer = partial(GlobalResponseNormMlp if use_grn else Mlp, use_conv=conv_mlp) self.use_conv_mlp = conv_mlp self.conv_dw = create_conv2d( in_chs, out_chs, kernel_size=kernel_size, stride=stride, dilation=dilation[0], depthwise=True, bias=conv_bias, ) self.norm = norm_layer(out_chs) self.mlp = mlp_layer(out_chs, int(mlp_ratio * out_chs), act_layer=act_layer) self.weight = nn.Parameter(ls_init_value * torch.ones(out_chs)) if ls_init_value is not None else None if in_chs != out_chs or stride != 1 or dilation[0] != dilation[1]: self.shortcut = Downsample(in_chs, out_chs, stride=stride, dilation=dilation[0]) else: self.shortcut = nn.Identity() self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity() def forward(self, x): shortcut = x x = self.conv_dw(x) if self.use_conv_mlp: x = self.norm(x) x = self.mlp(x) else: x = x.permute(0, 2, 3, 1) x = self.norm(x) x = self.mlp(x) x = x.permute(0, 3, 1, 2) if self.weight is not None: x = x.mul(self.weight.reshape(1, -1, 1, 1)) x = self.drop_path(x) + self.shortcut(shortcut) return x class ConvNeXtStage(nn.Module): def __init__( self, in_chs, out_chs, kernel_size=7, stride=2, depth=2, dilation=(1, 1), drop_path_rates=None, ls_init_value=1.0, conv_mlp=False, conv_bias=True, use_grn=False, act_layer='gelu', norm_layer=None, norm_layer_cl=None ): super().__init__() self.grad_checkpointing = True if in_chs != out_chs or stride > 1 or dilation[0] != dilation[1]: ds_ks = 2 if stride > 1 or dilation[0] != dilation[1] else 1 pad = 'same' if dilation[1] > 1 else 0 # same padding needed if dilation used self.downsample = nn.Sequential( norm_layer(in_chs), create_conv2d( in_chs, out_chs, kernel_size=ds_ks, stride=stride, dilation=dilation[0], padding=pad, bias=conv_bias, ), ) in_chs = out_chs else: self.downsample = nn.Identity() drop_path_rates = drop_path_rates or [0.] * depth stage_blocks = [] for i in range(depth): stage_blocks.append(ConvNeXtBlock( in_chs=in_chs, out_chs=out_chs, kernel_size=kernel_size, dilation=dilation[1], drop_path=drop_path_rates[i], ls_init_value=ls_init_value, conv_mlp=conv_mlp, conv_bias=conv_bias, use_grn=use_grn, act_layer=act_layer, norm_layer=norm_layer if conv_mlp else norm_layer_cl, )) in_chs = out_chs self.blocks = nn.Sequential(*stage_blocks) def forward(self, x): x = self.downsample(x) if self.grad_checkpointing and not torch.jit.is_scripting(): x = checkpoint_seq(self.blocks, x) else: x = self.blocks(x) return x class ConvNeXt(nn.Module): r""" ConvNeXt A PyTorch impl of : `A ConvNet for the 2020s` - https://arxiv.org/pdf/2201.03545.pdf """ def __init__( self, in_chans: int = 3, num_classes: int = 1024, global_pool: str = 'avg', output_stride: int = 32, depths: Tuple[int, ...] = (3, 3, 9, 3), dims: Tuple[int, ...] = (96, 192, 384, 768), kernel_sizes: Union[int, Tuple[int, ...]] = 7, ls_init_value: Optional[float] = 1e-6, stem_type: str = 'patch', patch_size: int = 4, head_init_scale: float = 1., head_norm_first: bool = False, head_hidden_size: Optional[int] = None, conv_mlp: bool = False, conv_bias: bool = True, use_grn: bool = False, act_layer: Union[str, Callable] = 'gelu', norm_layer: Optional[Union[str, Callable]] = None, norm_eps: Optional[float] = None, drop_rate: float = 0., drop_path_rate: float = 0., ): """ Args: in_chans: Number of input image channels. num_classes: Number of classes for classification head. global_pool: Global pooling type. output_stride: Output stride of network, one of (8, 16, 32). depths: Number of blocks at each stage. dims: Feature dimension at each stage. kernel_sizes: Depthwise convolution kernel-sizes for each stage. ls_init_value: Init value for Layer Scale, disabled if None. stem_type: Type of stem. patch_size: Stem patch size for patch stem. head_init_scale: Init scaling value for classifier weights and biases. head_norm_first: Apply normalization before global pool + head. head_hidden_size: Size of MLP hidden layer in head if not None and head_norm_first == False. conv_mlp: Use 1x1 conv in MLP, improves speed for small networks w/ chan last. conv_bias: Use bias layers w/ all convolutions. use_grn: Use Global Response Norm (ConvNeXt-V2) in MLP. act_layer: Activation layer type. norm_layer: Normalization layer type. drop_rate: Head pre-classifier dropout rate. drop_path_rate: Stochastic depth drop rate. """ super().__init__() assert output_stride in (8, 16, 32) kernel_sizes = to_ntuple(4)(kernel_sizes) if norm_layer is None: norm_layer = LayerNorm2d norm_layer_cl = norm_layer if conv_mlp else LayerNorm if norm_eps is not None: norm_layer = partial(norm_layer, eps=norm_eps) norm_layer_cl = partial(norm_layer_cl, eps=norm_eps) else: assert conv_mlp,\ 'If a norm_layer is specified, conv MLP must be used so all norm expect rank-4, channels-first input' norm_layer_cl = norm_layer if norm_eps is not None: norm_layer_cl = partial(norm_layer_cl, eps=norm_eps) self.num_classes = num_classes self.drop_rate = drop_rate self.feature_info = [] assert stem_type in ('patch', 'overlap', 'overlap_tiered') if stem_type == 'patch': # NOTE: this stem is a minimal form of ViT PatchEmbed, as used in SwinTransformer w/ patch_size = 4 self.stem = nn.Sequential( nn.Conv2d(in_chans, dims[0], kernel_size=patch_size, stride=patch_size, bias=conv_bias), norm_layer(dims[0]), ) stem_stride = patch_size else: mid_chs = make_divisible(dims[0] // 2) if 'tiered' in stem_type else dims[0] self.stem = nn.Sequential( nn.Conv2d(in_chans, mid_chs, kernel_size=3, stride=2, padding=1, bias=conv_bias), nn.Conv2d(mid_chs, dims[0], kernel_size=3, stride=2, padding=1, bias=conv_bias), norm_layer(dims[0]), ) stem_stride = 4 self.stages = nn.Sequential() dp_rates = [x.tolist() for x in torch.linspace(0, drop_path_rate, sum(depths)).split(depths)] stages = [] prev_chs = dims[0] curr_stride = stem_stride dilation = 1 # 4 feature resolution stages, each consisting of multiple residual blocks for i in range(4): stride = 2 if curr_stride == 2 or i > 0 else 1 if curr_stride >= output_stride and stride > 1: dilation *= stride stride = 1 curr_stride *= stride first_dilation = 1 if dilation in (1, 2) else 2 out_chs = dims[i] stages.append(ConvNeXtStage( prev_chs, out_chs, kernel_size=kernel_sizes[i], stride=stride, dilation=(first_dilation, dilation), depth=depths[i], drop_path_rates=dp_rates[i], ls_init_value=ls_init_value, conv_mlp=conv_mlp, conv_bias=conv_bias, use_grn=use_grn, act_layer=act_layer, norm_layer=norm_layer, norm_layer_cl=norm_layer_cl, )) prev_chs = out_chs # NOTE feature_info use currently assumes stage 0 == stride 1, rest are stride 2 self.feature_info += [dict(num_chs=prev_chs, reduction=curr_stride, module=f'stages.{i}')] self.stages = nn.Sequential(*stages) self.num_features = prev_chs # if head_norm_first == true, norm -> global pool -> fc ordering, like most other nets # otherwise pool -> norm -> fc, the default ConvNeXt ordering (pretrained FB weights) if head_norm_first: assert not head_hidden_size self.norm_pre = norm_layer(self.num_features) self.head = ClassifierHead( self.num_features, num_classes, pool_type=global_pool, drop_rate=self.drop_rate, ) else: self.norm_pre = nn.Identity() self.head = NormMlpClassifierHead( self.num_features, num_classes, hidden_size=head_hidden_size, pool_type=global_pool, drop_rate=self.drop_rate, norm_layer=norm_layer, act_layer='gelu', ) named_apply(partial(_init_weights, head_init_scale=head_init_scale), self) @torch.jit.ignore def group_matcher(self, coarse=False): return dict( stem=r'^stem', blocks=r'^stages\.(\d+)' if coarse else [ (r'^stages\.(\d+)\.downsample', (0,)), # blocks (r'^stages\.(\d+)\.blocks\.(\d+)', None), (r'^norm_pre', (99999,)) ] ) @torch.jit.ignore def set_grad_checkpointing(self, enable=True): for s in self.stages: s.grad_checkpointing = enable @torch.jit.ignore def get_classifier(self): return self.head.fc def reset_classifier(self, num_classes=0, global_pool=None): self.head.reset(num_classes, global_pool) def forward_features(self, x): x = self.stem(x) x = self.stages(x) x = self.norm_pre(x) return x def forward_head(self, x, pre_logits: bool = False): return self.head(x, pre_logits=True) if pre_logits else self.head(x) def forward(self, x): x = self.forward_features(x) x = self.forward_head(x) return x def _init_weights(module, name=None, head_init_scale=1.0): if isinstance(module, nn.Conv2d): trunc_normal_(module.weight, std=.02) if module.bias is not None: nn.init.zeros_(module.bias) elif isinstance(module, nn.Linear): trunc_normal_(module.weight, std=.02) nn.init.zeros_(module.bias) if name and 'head.' in name: module.weight.data.mul_(head_init_scale) module.bias.data.mul_(head_init_scale) cfg={ "crop_size": 256, "do_center_crop": True, "do_normalize": True, "do_resize": True, "feature_extractor_type": "CLIPFeatureExtractor", "image_mean": [ 0.48145466, 0.4578275, 0.40821073 ], "image_std": [ 0.26862954, 0.26130258, 0.27577711 ], "resample": 3, "size": 256 } class ConvNextVisionTower(nn.Module): def __init__(self, vision_tower, args, delay_load=False): super().__init__() self.is_loaded = False self.freeze_vision=False self.input_image_size=args.input_image_size self.vision_tower_name = vision_tower self.select_layer = -1 # hardcode self.select_feature = getattr(args, 'mm_vision_select_feature', 'patch') self.xpfs = args.xpfs if hasattr(args, 'xpfs') else None print(f"self.xpfs:{self.xpfs}") def load_model(self, gradient_checkpointing=True): self.image_processor = CLIPImageProcessor(**cfg) if 'xxlarge' in self.vision_tower_name: model_args = dict( depths=[3, 4, 30, 3], dims=[384, 768, 1536, 3072], norm_eps=1e-5, num_classes=1024 ) self.vision_tower = ConvNeXt(**model_args) setattr(self.vision_tower, 'hidden_size', 3072) else: raise NotImplementedError if self.freeze_vision: self.vision_tower.requires_grad_(False) for s in self.vision_tower.stages: s.grad_checkpointing = gradient_checkpointing if self.input_image_size is not None: self.image_processor.size=self.input_image_size self.image_processor.crop_size={ 'height':self.input_image_size, 'width': self.input_image_size } self.is_loaded = True def feature_select(self, image_forward_outs): image_features = image_forward_outs[self.select_layer] return image_features def forward_features(self, x): x = self.vision_tower.stem(x) image_forward_out=[] for blk in self.vision_tower.stages: x = torch.utils.checkpoint.checkpoint(blk, x) b,c,h,w=x.shape image_forward_out.append(x.view(b,c,-1).transpose(1,2)) return image_forward_out def forward(self, images): if self.freeze_vision: with torch.no_grad(): image_features = self._forward_images(images) else: image_features = self._forward_images(images) return image_features def _forward_images(self, images): image_forward_outs = self.forward_features(images.to(device=self.device, dtype=self.dtype)) image_features = self.feature_select(image_forward_outs) return image_features @property def dummy_feature(self): return torch.zeros(1, self.hidden_size, device=self.device, dtype=self.dtype) @property def dtype(self): return next(self.vision_tower.parameters()).dtype @property def device(self): return next(self.vision_tower.parameters()).device @property def config(self): assert NotImplementedError pass @property def num_attention_heads(self): # as constant return 16 @property def num_layers(self): # as constant return 4 @property def hidden_size(self): return self.vision_tower.hidden_size @property def num_patches(self): return (cfg['image_size'] // self.patch_embed.patch_size[0]) ** 2