File size: 6,804 Bytes
e19aac6
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
# This file is modified from https://github.com/haotian-liu/LLaVA/

from abc import abstractmethod

import torch
import torch.nn as nn
from accelerate.hooks import add_hook_to_module
from transformers import AutoConfig, PreTrainedModel
from transformers.image_processing_utils import BaseImageProcessor
from transformers.integrations.deepspeed import is_deepspeed_zero3_enabled


class VisionTower(nn.Module):
    def __init__(self, vision_tower, args, delay_load=False):
        super().__init__()

        self.is_loaded = False

        self.vision_tower_name = vision_tower
        self.select_layer = getattr(args, "mm_vision_select_layer", -2)
        self.select_feature = getattr(args, "mm_vision_select_feature", "patch")

        self.cfg_only = None

    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[:, 1:]
        elif self.select_feature == "cls_patch":
            image_features = image_features
        else:
            raise ValueError(f"Unexpected select feature: {self.select_feature}")
        return image_features

    def _maybe_resize_pos_embeds(
        self,
        model: PreTrainedModel,
        image_processor: BaseImageProcessor,
        resolution: int = -1,
        interpolate_mode: str = "linear",
    ):
        if resolution in [model.config.image_size, -1]:
            return
        print(f"Resizing vision model's position embeddings to support higher vision resolution: from {model.config.image_size} to {resolution} ...")
        embeddings = model.vision_model.embeddings
        patch_size = embeddings.patch_size
        num_new_tokens = int((resolution // patch_size) ** 2)

        old_embeddings = embeddings.position_embedding
        match interpolate_mode:
            case "linear":
                ## Step 1: Calculate the corresponding patch ID (pid) in the current resolution (M patches) based on the target resolution (N patches). Formula: pid = pid / N * M
                ## Step 2:  Obtain new embeddings by interpolating between the embeddings of the two nearest calculated patch IDs. Formula: new_embeds = (pid - floor(pid)) * embeds[ceil(pid)] + (ceil(pid) - pid) * embeds[floor(pid)]
                import torch
                import torch.nn as nn

                if is_deepspeed_zero3_enabled():
                    import deepspeed

                    with deepspeed.zero.GatheredParameters([old_embeddings.weight], modifier_rank=None):
                        old_num_tokens, old_embedding_dim = old_embeddings.weight.size()
                else:
                    old_num_tokens, old_embedding_dim = old_embeddings.weight.size()
                new_embeddings = nn.Embedding(
                    num_new_tokens,
                    old_embedding_dim,
                    dtype=old_embeddings.weight.dtype,
                    device=old_embeddings.weight.device,
                )
                mapped_indices = (
                    torch.arange(num_new_tokens).to(old_embeddings.weight.device)
                    / (num_new_tokens - 1)
                    * (old_num_tokens - 1)
                )
                floor_indices = torch.clamp(mapped_indices.floor().long(), min=0, max=old_num_tokens - 1)
                ceil_indices = torch.clamp(mapped_indices.ceil().long(), min=0, max=old_num_tokens - 1)
                if is_deepspeed_zero3_enabled():
                    params = [old_embeddings.weight, new_embeddings.weight]
                    with deepspeed.zero.GatheredParameters(params, modifier_rank=0):
                        interpolated_embeds = (mapped_indices - floor_indices)[:, None] * old_embeddings.weight.data[
                            ceil_indices, :
                        ] + (ceil_indices - mapped_indices)[:, None] * old_embeddings.weight.data[floor_indices, :]
                else:
                    interpolated_embeds = (mapped_indices - floor_indices)[:, None] * old_embeddings.weight.data[
                        ceil_indices, :
                    ] + (ceil_indices - mapped_indices)[:, None] * old_embeddings.weight.data[floor_indices, :]
                new_embeddings.weight.data = interpolated_embeds
            case _:
                raise NotImplementedError

        if hasattr(old_embeddings, "_hf_hook"):
            hook = old_embeddings._hf_hook
            add_hook_to_module(new_embeddings, hook)
        new_embeddings.requires_grad_(old_embeddings.weight.requires_grad)
        ## update vision encoder's configurations
        model.config.image_size = resolution
        if hasattr(image_processor, "crop_size"):
            # CLIP vision tower
            image_processor.crop_size = resolution
        else:
            # SIGLIP vision tower
            assert hasattr(image_processor, "size")
            image_processor.size = {"height": resolution, "width": resolution}
        ## TODO define a '_reinitialize' method for VisionTower
        embeddings.position_embedding = new_embeddings
        embeddings.image_size = resolution
        embeddings.num_patches = embeddings.num_positions = num_new_tokens
        embeddings.position_ids = (
            torch.arange(embeddings.num_positions).expand((1, -1)).to(old_embeddings.weight.device)
        )

    def forward(self, images, **kwargs):
        if type(images) is list:
            image_features = []
            for image in images:
                image_forward_out = self.vision_tower(
                    image.to(device=self.device, dtype=self.dtype).unsqueeze(0),
                    output_hidden_states=True, **kwargs,
                )
                image_feature = self.feature_select(image_forward_out).to(image.dtype)
                image_features.append(image_feature)
        else:
            image_forward_outs = self.vision_tower(
                images.to(device=self.device, dtype=self.dtype),
                output_hidden_states=True, **kwargs,
            )
            image_features = self.feature_select(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_tower.dtype

    @property
    def device(self):
        return self.vision_tower.device

    @property
    def config(self):
        if self.is_loaded:
            return self.vision_tower.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