Wenxuan123/capvector
013
1"""2processing_prismatic.py3 4HuggingFace-style preprocessor definitions for Prismatic VLMs, inheriting from `ProcessorMixin`. Default configuration5specifies `siglip-224px+7b`.6"""7 8from typing import Any, ClassVar, List, Optional, Tuple, Union9 10import timm.data11import torch12import torchvision.transforms.functional as TVF13from PIL import Image14from torchvision.transforms import CenterCrop, Compose, Normalize, Resize, ToTensor15from transformers import PreTrainedTokenizerBase16from transformers.image_processing_utils import BatchFeature, ImageProcessingMixin17from transformers.processing_utils import ProcessorMixin18from transformers.tokenization_utils import PaddingStrategy, PreTokenizedInput, TextInput, TruncationStrategy19from transformers.utils import TensorType20 21 22# === Image Processing ===23def letterbox_pad_transform(image: Image.Image, padding_fill_value: Tuple[int, int, int]) -> Image.Image:24 """Given a PIL.Image, pad to square by adding a symmetric border around the height/width."""25 (w, h), max_wh = image.size, max(image.size)26 horizontal_pad, vertical_pad = int((max_wh - w) / 2), int((max_wh - h) / 2)27 padding = (horizontal_pad, vertical_pad, horizontal_pad, vertical_pad)28 29 return TVF.pad(image, padding, fill=padding_fill_value, padding_mode="constant")30 31 32class PrismaticImageProcessor(ImageProcessingMixin):33 model_input_names: ClassVar[List[str]] = ["pixel_values"]34 35 def __init__(36 self,37 use_fused_vision_backbone: bool = False,38 image_resize_strategy: str = "letterbox",39 input_sizes: Optional[List[Tuple[int, int, int]]] = None,40 interpolations: Optional[List[str]] = None,41 means: Optional[List[Tuple[float, float, float]]] = None,42 stds: Optional[List[Tuple[float, float, float]]] = None,43 **kwargs: str,44 ) -> None:45 """46 Initialize a PrismaticImageProcessor as a wrapper around a torchvision transform; this transform will be47 created by TIMM, and edited to follow our custom `image_resize_strategy` logic.48 49 @param use_fused_vision_backbone: Boolean indicating single or fused (dual) vision backbone50 @param image_resize_strategy: Prismatic image resize strategy in < resize-naive | resize-crop | letterbox >51 @param input_size: [TIMM :: `data_cfg`] Input image size as tuple (channels, width, height)52 @param interpolation: [TIMM :: `data_cfg`] Interpolation as string (default: "bicubic")53 @param mean: [TIMM :: `data_cfg`] Normalization mean as float tuple (or two-tuple if `fused_backbone`)54 @param std: [TIMM :: `data_cfg`] Normalization std as float tuple (or two-tuple if `fused_backbone`)55 """56 self.use_fused_vision_backbone = use_fused_vision_backbone57 self.image_resize_strategy = image_resize_strategy58 59 # Handle `None` default values60 input_sizes = [(3, 224, 224)] if input_sizes is None else input_sizes61 means = [(0.5, 0.5, 0.5)] if means is None else means62 stds = [(0.5, 0.5, 0.5)] if stds is None else stds63 64 # TIMM `data_cfg` Parameters65 self.input_sizes, self.interpolations, self.means, self.stds = input_sizes, interpolations, means, stds66 67 # Grab torchvision transforms via TIMM =>> need to parse for specific "functional" transform values!68 self.tvf_resize_params, self.tvf_crop_params, self.tvf_normalize_params = [], [], []69 self.tvf_do_letterbox, self.tvf_letterbox_fill = False, None70 71 for idx in range(len(input_sizes)):72 transform = timm.data.create_transform(73 input_size=self.input_sizes[idx],74 interpolation=self.interpolations[idx],75 mean=self.means[idx],76 std=self.stds[idx],77 crop_pct=1.0, # Set to 1.0 to ignore cropping (initial Resize sets `input_size`)78 crop_mode="center", # Default crop mode -- no-op when `crop_pct == 1.0`79 is_training=False, # No image augmentations when loading the transform!80 )81 82 # [Validation] Ensure appropriate transform structure, expected sizes83 if not (84 isinstance(transform, Compose)85 and (len(transform.transforms) == 4)86 and isinstance(transform.transforms[0], Resize)87 and isinstance(transform.transforms[1], CenterCrop)88 and isinstance(transform.transforms[2], ToTensor)89 and isinstance(transform.transforms[3], Normalize)90 and (transform.transforms[0].size == self.input_sizes[idx][-1])91 and (transform.transforms[1].size == self.input_sizes[idx][-2:])92 ):93 raise ValueError(f"Unexpected TIMM image transformation structure/sizes: `{transform}`")94 95 # HF Image Processors *must* be JSON-serializable; as such, cannot have torchvision. as an attribute.96 # => Instead, we're going to parse the transform and call "torchvision.transforms.functional" (`tvf`)97 resize_t, crop_t, norm_t = transform.transforms[0], transform.transforms[1], transform.transforms[3]98 self.tvf_resize_params.append(99 {100 "size": resize_t.size,101 "interpolation": TVF.pil_modes_mapping[resize_t.interpolation],102 "max_size": None,103 "antialias": True,104 }105 )106 self.tvf_crop_params.append({"output_size": crop_t.size})107 self.tvf_normalize_params.append(108 {109 "mean": norm_t.mean.float().numpy().tolist(),110 "std": norm_t.std.float().numpy().tolist(),111 "inplace": False,112 }113 )114 self.tvf_do_letterbox, self.tvf_letterbox_fill = False, None115 116 # Handle Prismatic `image_resize_strategy`117 if self.image_resize_strategy == "resize-naive":118 self.tvf_resize_params[idx]["size"] = (resize_t.size, resize_t.size)119 elif self.image_resize_strategy == "letterbox":120 self.tvf_do_letterbox, self.tvf_letterbox_fill = True, tuple([int(x * 255) for x in self.means[idx]])121 elif self.image_resize_strategy == "resize-crop":122 pass123 else:124 raise ValueError(f"Image resize strategy `{self.image_resize_strategy}` is not supported!")125 126 # Dispatch **kwargs to super()127 super().__init__(**kwargs)128 129 def apply_transform(self, img: Image.Image) -> torch.Tensor:130 """Apply `functional` variant of TIMM's Transform = Compose([Resize -> CenterCrop -> ToTensor -> Normalize])"""131 if self.tvf_do_letterbox:132 img = letterbox_pad_transform(img, self.tvf_letterbox_fill)133 134 # [Contract] Fused Backbones expect "channel-stacked" inputs; we'll unpack on the model side!135 imgs_t = []136 for idx in range(len(self.input_sizes)):137 img_idx = TVF.resize(img, **self.tvf_resize_params[idx])138 img_idx = TVF.center_crop(img_idx, **self.tvf_crop_params[idx])139 img_idx_t = TVF.to_tensor(img_idx)140 img_idx_t = TVF.normalize(img_idx_t, **self.tvf_normalize_params[idx])141 imgs_t.append(img_idx_t)142 143 # [Contract] `imgs_t` is a list of Tensors of shape [3, input_size, input_size]; stack along dim = 0144 img_t = torch.vstack(imgs_t)145 146 return img_t147 148 def preprocess(149 self,150 images: Union[Image.Image, List[Image.Image]],151 return_tensors: Optional[Union[str, TensorType]] = None,152 **_: str,153 ) -> BatchFeature:154 """155 Preprocess an image (or batch of images); note that unlike the `transformers :: BaseImageProcessor` we156 explicitly only handle PIL.Image.Image instances for simplicity.157 158 @param images: A (batch of) PIL.Image.Image instance(s) to preprocess.159 @param return_tensors: BatchFeature default Tensor format (e.g., "pt" for torch); if None, returns np.ndarray160 161 @return: Instance of `transformers :: BatchFeature` with a single key "pixel_values"162 """163 if not isinstance(images, list):164 images = [images]165 166 # Apply `self.img_transform` to each image (will return list of torch.Tensors); stack into "batched" Tensor167 pixel_values = torch.stack([self.apply_transform(img.convert("RGB")) for img in images])168 169 # Return BatchFeature =>> note that for compatibility, constructor expects Dict[str, np.ndarray], so we convert170 return BatchFeature(data={"pixel_values": pixel_values.float().numpy()}, tensor_type=return_tensors)171 172 def __call__(self, images: Union[Image.Image, List[Image.Image]], **kwargs) -> BatchFeature:173 return self.preprocess(images, **kwargs)174 175 176# === PrismaticProcessor =>> Wraps both ImageProcessor and Tokenizer ===177# =>> https://github.com/huggingface/transformers/blob/main/src/transformers/models/llava/processing_llava.py178class PrismaticProcessor(ProcessorMixin):179 attributes: ClassVar[List[str]] = ["image_processor", "tokenizer"]180 image_processor_class: str = "AutoImageProcessor"181 tokenizer_class: str = "AutoTokenizer"182 183 def __init__(184 self,185 image_processor: Optional[ImageProcessingMixin] = None,186 tokenizer: Optional[PreTrainedTokenizerBase] = None,187 ) -> None:188 super().__init__(image_processor, tokenizer)189 190 def __call__(191 self,192 text: Union[TextInput, PreTokenizedInput, List[TextInput], List[PreTokenizedInput]],193 images: Union[Image.Image, List[Image.Image]],194 padding: Union[bool, str, PaddingStrategy] = False,195 truncation: Optional[Union[bool, str, TruncationStrategy]] = None,196 max_length: Optional[int] = None,197 return_tensors: Optional[Union[str, TensorType]] = TensorType.PYTORCH,198 ) -> BatchFeature:199 """200 Preprocess a given (batch) of text/images for a Prismatic VLM; forwards text to the underlying LLM's tokenizer,201 forwards images to PrismaticImageProcessor.202 203 @param text: The (batch) of text to encode; must be a string or list of strings.204 @param images: A (batch of) PIL.Image.Image instance(s) to preprocess.205 @param padding: Sequence padding strategy (if multiple specified) in < True = "longest" | "max_length" | False >206 @param truncation: Truncation strategy for the output sequences; requires `max_length` to be specified207 @param max_length: Maximum length (in tokens) to truncate208 @param return_tensors: Type of return tensors (usually "pt" or TensorType.PYTORCH)209 210 @return: BatchFeature with keys for `input_ids`, `attention_mask` and `pixel_values`.211 """212 pixel_values = self.image_processor(images, return_tensors=return_tensors)["pixel_values"]213 text_inputs = self.tokenizer(214 text, return_tensors=return_tensors, padding=padding, truncation=truncation, max_length=max_length215 )216 217 # [Validate] Need same number of images and text inputs!218 if pixel_values.shape[0] != text_inputs.input_ids.shape[0]:219 raise ValueError("Batch is malformed; expected same number of images and text inputs!")220 221 return BatchFeature(data={**text_inputs, "pixel_values": pixel_values})222 223 # === Tokenizer Dispatch Utilities =>> check `PreTrainedTokenizerBase` for documentation ===224 def batch_decode(225 self,226 sequences: Union[List[int], List[List[int]], torch.Tensor, Any], # `Any` = np.ndarray | tf.Tensor227 skip_special_tokens: bool = False,228 clean_up_tokenization_spaces: Optional[bool] = None,229 **kwargs: str,230 ) -> List[str]:231 return self.tokenizer.batch_decode(232 sequences=sequences,233 skip_special_tokens=skip_special_tokens,234 clean_up_tokenization_spaces=clean_up_tokenization_spaces,235 **kwargs,236 )237 238 def decode(239 self,240 token_ids: Union[int, List[int], torch.Tensor, Any], # `Any` = np.ndarray | tf.Tensor241 skip_special_tokens: bool = False,242 clean_up_tokenization_spaces: Optional[bool] = None,243 **kwargs: str,244 ) -> str:245 return self.tokenizer.decode(246 token_ids=token_ids,247 skip_special_tokens=skip_special_tokens,248 clean_up_tokenization_spaces=clean_up_tokenization_spaces,249 **kwargs,250 )251 252 @property253 def model_input_names(self) -> List[str]:254 tokenizer_input_names = self.tokenizer.model_input_names255 image_processor_input_names = self.image_processor.model_input_names256 257 return list(dict.fromkeys(tokenizer_input_names + image_processor_input_names))258 