File size: 6,609 Bytes
ee21b96
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
# Copyright 2022 The OFA-Sys Team.
# All rights reserved.
# This source code is licensed under the Apache 2.0 license
# found in the LICENSE file in the root directory.

from io import BytesIO

import logging
import warnings
import random
import functools

import torch
import base64
from torchvision import transforms
from torchvision.transforms import InterpolationMode
from torchvision.transforms import functional as F

from PIL import Image, ImageFile

from zhconv import convert
import unicodedata

from data import data_utils
from data.ofa_dataset import OFADataset

ImageFile.LOAD_TRUNCATED_IMAGES = True
ImageFile.MAX_IMAGE_PIXELS = None
Image.MAX_IMAGE_PIXELS = None

logger = logging.getLogger(__name__)
warnings.filterwarnings("ignore", "(Possibly )?corrupt EXIF data", UserWarning)

IMAGENET_DEFAULT_MEAN = (0.485, 0.456, 0.406)
IMAGENET_DEFAULT_STD = (0.229, 0.224, 0.225)


def collate(samples, pad_idx, eos_idx):
    if len(samples) == 0:
        return {}

    def merge(key):
        return data_utils.collate_tokens(
            [s[key] for s in samples],
            pad_idx,
            eos_idx=eos_idx,
        )

    id = np.array([s["id"] for s in samples])
    src_tokens = merge("source")
    src_lengths = torch.LongTensor([s["source"].ne(pad_idx).long().sum() for s in samples])

    patch_images = torch.stack([sample['patch_image'] for sample in samples], dim=0)
    patch_masks = torch.cat([sample['patch_mask'] for sample in samples])

    prev_output_tokens = None
    target = None
    if samples[0].get("target", None) is not None:
        target = merge("target")
        tgt_lengths = torch.LongTensor([s["target"].ne(pad_idx).long().sum() for s in samples])
        ntokens = tgt_lengths.sum().item()

        if samples[0].get("prev_output_tokens", None) is not None:
            prev_output_tokens = merge("prev_output_tokens")
    else:
        ntokens = src_lengths.sum().item()

    batch = {
        "id": id,
        "nsentences": len(samples),
        "ntokens": ntokens,
        "net_input": {
            "src_tokens": src_tokens,
            "src_lengths": src_lengths,
            "patch_images": patch_images,
            "patch_masks": patch_masks,
            "prev_output_tokens": prev_output_tokens
        },
        "target": target,
    }

    return batch


def ocr_resize(img, patch_image_size, is_document=False):
    img = img.convert("RGB")
    width, height = img.size

    if is_document:
        new_height, new_width = 64, 1920
    else:
        if width >= height:
            new_width = max(64, patch_image_size)
            new_height = max(64, int(patch_image_size * (height / width)))
            top = random.randint(0, patch_image_size - new_height)
            bottom = patch_image_size - new_height - top
            left, right = 0, 0
        else:
            new_height = max(64, patch_image_size)
            new_width = max(64, int(patch_image_size * (width / height)))
            left = random.randint(0, patch_image_size - new_width)
            right = patch_image_size - new_width - left
            top, bottom = 0, 0

    img_new = F.resize(
        img,
        [new_height, new_width],
        interpolation=InterpolationMode.BICUBIC,
    )

    if is_document:
        img_split = transforms.ToTensor()(img_new).chunk(4, dim=-1)
        img_new = transforms.ToPILImage()(torch.cat(img_split, dim=-2))
        new_width, new_height = img_new.size
        top = random.randint(0, patch_image_size - new_height)
        bottom = patch_image_size - new_height - top
        left, right = 0, 0

    img_new = F.pad(img_new, padding=[left, top, right, bottom], padding_mode="edge")
    assert img_new.size == (patch_image_size, patch_image_size)

    return img_new


class OcrDataset(OFADataset):
    def __init__(
        self,
        split,
        dataset,
        bpe,
        src_dict,
        tgt_dict=None,
        max_src_length=80,
        max_tgt_length=30,
        patch_image_size=224,
        imagenet_default_mean_and_std=False,
        is_document=False,
    ):
        super().__init__(split, dataset, bpe, src_dict, tgt_dict)
        self.max_src_length = max_src_length
        self.max_tgt_length = max_tgt_length
        self.patch_image_size = patch_image_size

        if imagenet_default_mean_and_std:
            mean = IMAGENET_DEFAULT_MEAN
            std = IMAGENET_DEFAULT_STD
        else:
            mean = [0.5, 0.5, 0.5]
            std = [0.5, 0.5, 0.5]

        self.patch_resize_transform = transforms.Compose(
            [
                lambda image: ocr_resize(
                    image, patch_image_size, is_document=is_document
                ),
                transforms.ToTensor(),
                transforms.Normalize(mean=mean, std=std),
            ]
        )

        self.bpe = bpe
        if type(bpe).__name__ == 'GPT2BPE':
            self.prompt = " what are the texts on the image?"
        elif type(bpe).__name__ == 'BertBPE':
            self.prompt = "图片上的文字是什么?"

    def __getitem__(self, index):
        uniq_id, image, caption = self.dataset[index]

        image = Image.open(BytesIO(base64.urlsafe_b64decode(image)))
        patch_image = self.patch_resize_transform(image)
        patch_mask = torch.tensor([True])

        caption = unicodedata.normalize("NFKC", convert(caption, "zh-hans"))
        if type(self.bpe).__name__ == 'GPT2BPE':
            caption_token_list = caption.lower().strip().split()
            tgt_caption = ' '.join(caption_token_list[:self.max_tgt_length])
        elif type(self.bpe).__name__ == 'BertBPE':
            tgt_caption = caption[: self.max_tgt_length].lower()
        src_item = self.encode_text(self.prompt)
        tgt_item = self.encode_text(" {}".format(tgt_caption))

        src_item = torch.cat([self.bos_item, src_item, self.eos_item])
        target_item = torch.cat([tgt_item, self.eos_item])
        prev_output_item = torch.cat([self.bos_item, tgt_item])

        example = {
            "id": uniq_id,
            "source": src_item,
            "patch_image": patch_image,
            "patch_mask": patch_mask,
            "target": target_item,
            "prev_output_tokens": prev_output_item,
        }
        return example

    def collater(self, samples, pad_to_length=None):
        """Merge a list of samples to form a mini-batch.
        Args:
            samples (List[dict]): samples to collate
        Returns:
            dict: a mini-batch containing the data required for the task
        """
        return collate(samples, pad_idx=self.pad, eos_idx=self.eos)