initial commit

models/backbones/clip_vision_encoder.py

@@ -0,0 +1,83 @@
+import torch
+import torch.nn as nn
+
+from transformers import CLIPVisionModel, CLIPImageProcessor, CLIPVisionConfig
+
+
+class CLIPVisionEncoder(nn.Module):
+    def __init__(self, encoder_name="openai/clip-vit-large-patch14",  delay_load=False):
+        super().__init__()
+
+        self.is_loaded = False
+
+        self.vision_encoder_name = encoder_name
+        # self.select_layer = args.mm_vision_select_layer
+        # self.select_feature = getattr(args, 'mm_vision_select_feature', 'patch')
+        self.select_layer = -1
+        self.select_feature = "patch"
+        if not delay_load:
+            self.load_model()
+        else:
+            self.cfg_only = CLIPVisionConfig.from_pretrained(self.vision_encoder_name)
+
+    def load_model(self):
+        self.image_processor = CLIPImageProcessor.from_pretrained(self.vision_encoder_name)
+        self.vision_encoder = CLIPVisionModel.from_pretrained(self.vision_encoder_name)
+        self.vision_encoder.requires_grad_(False)
+
+        self.is_loaded = True
+
+    def feature_select(self, image_forward_outs):
+        image_features = image_forward_outs.hidden_states[self.select_layer]
+        if self.select_feature == 'patch':
+            image_features = image_features[:, :]
+        elif self.select_feature == 'cls_patch':
+            image_features = image_features
+        else:
+            raise ValueError(f'Unexpected select feature: {self.select_feature}')
+        return image_features
+
+    @torch.no_grad()
+    def forward(self, images):
+        if type(images) is list:
+            image_features = []
+            for image in images:
+                image_forward_out = self.vision_encoder(image.to(device=self.device, dtype=self.dtype).unsqueeze(0), output_hidden_states=True)
+                image_feature = self.feature_select(image_forward_out).to(image.dtype)
+                image_features.append(image_feature)
+        else:
+            image_forward_outs = self.vision_encoder(images.to(device=self.device, dtype=self.dtype), output_hidden_states=True)
+            image_features = self.feature_select(image_forward_outs).to(images.dtype)
+            # print("image feature shape", image_features.shape)
+            # print(type(image_forward_outs))
+            # print(type(image_forward_outs.shape))
+            # image_features = image_forward_outs.to(images.dtype)
+
+        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 self.vision_encoder.dtype
+
+    @property
+    def device(self):
+        return self.vision_encoder.device
+
+    @property
+    def config(self):
+        if self.is_loaded:
+            return self.vision_encoder.config
+        else:
+            return self.cfg_only
+
+    @property
+    def hidden_size(self):
+        return self.config.hidden_size
+
+    @property
+    def num_patches(self):
+        return (self.config.image_size // self.config.patch_size) ** 2