File size: 21,524 Bytes
c022250
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
# Copyright (c) Alibaba Cloud.
#
# This source code is licensed under the license found in the
# LICENSE file in the root directory of this source tree.

"""Tokenization classes for QWen."""

import base64
import logging
import os
import requests
import unicodedata
from typing import Collection, Dict, List, Set, Tuple, Union, Any, Callable, Optional

import tiktoken
import numpy as np
from PIL import Image
from PIL import ImageFont
from PIL import ImageDraw
from transformers import PreTrainedTokenizer, AddedToken
from transformers.utils import try_to_load_from_cache

import matplotlib.colors as mcolors
from matplotlib.font_manager import FontProperties

logger = logging.getLogger(__name__)


VOCAB_FILES_NAMES = {"vocab_file": "qwen.tiktoken", "ttf": "SimSun.ttf"}
FONT_PATH = try_to_load_from_cache("Qwen/Qwen-VL-Chat", "SimSun.ttf")
if FONT_PATH is None:
    if not os.path.exists("SimSun.ttf"):
        ttf = requests.get("https://qianwen-res.oss-cn-beijing.aliyuncs.com/Qwen-VL/assets/SimSun.ttf")
        open("SimSun.ttf", "wb").write(ttf.content)
    FONT_PATH = "SimSun.ttf"

PAT_STR = r"""(?i:'s|'t|'re|'ve|'m|'ll|'d)|[^\r\n\p{L}\p{N}]?\p{L}+|\p{N}| ?[^\s\p{L}\p{N}]+[\r\n]*|\s*[\r\n]+|\s+(?!\S)|\s+"""
ENDOFTEXT = "<|endoftext|>"
IMSTART = "<|im_start|>"
IMEND = "<|im_end|>"
# as the default behavior is changed to allow special tokens in
# regular texts, the surface forms of special tokens need to be
# as different as possible to minimize the impact
EXTRAS = tuple((f"<|extra_{i}|>" for i in range(205)))
SPECIAL_TOKENS = (
    ENDOFTEXT,
    IMSTART,
    IMEND,
) + EXTRAS
IMG_TOKEN_SPAN = 256


def _load_tiktoken_bpe(tiktoken_bpe_file: str) -> Dict[bytes, int]:
    with open(tiktoken_bpe_file, "rb") as f:
        contents = f.read()
    return {
        base64.b64decode(token): int(rank)
        for token, rank in (line.split() for line in contents.splitlines() if line)
    }

def _list_find(
    input_list: List[Any],
    candidates: Tuple[Any],
    start: int = 0,
):
    for i in range(start, len(input_list)):
        if input_list[i] in candidates:
            return i
    return -1

def _replace_closed_tag(
    input_tokens: List[Any],
    start_tags: Union[Any, Tuple[Any]],
    end_tags: Union[Any, Tuple[Any]],
    inclusive_replace_func: Callable,
    exclusive_replace_func: Callable = lambda x: x,
):
    if isinstance(start_tags, (str, int)):
        start_tags = (start_tags,)
    if isinstance(end_tags, (str, int)):
        end_tags = (end_tags,)
    assert len(start_tags) == len(end_tags)

    output_tokens = []
    end = 0
    while True:
        start = _list_find(input_tokens, start_tags, end)
        if start == -1:
            break
        output_tokens.extend(exclusive_replace_func(input_tokens[end : start]))
        tag_idx = start_tags.index(input_tokens[start])
        end = _list_find(input_tokens, (end_tags[tag_idx],), start)
        if end == -1:
            raise ValueError("Unclosed image token")
        output_tokens.extend(inclusive_replace_func(input_tokens[start : end + 1]))
        end += 1
    output_tokens.extend(exclusive_replace_func(input_tokens[end : ]))
    return output_tokens

class QWenTokenizer(PreTrainedTokenizer):
    """QWen tokenizer."""

    vocab_files_names = VOCAB_FILES_NAMES

    def __init__(
        self,
        vocab_file,
        errors="replace",
        image_start_tag='<img>',
        image_end_tag='</img>',
        image_pad_tag='<imgpad>',
        ref_start_tag='<ref>',
        ref_end_tag='</ref>',
        box_start_tag='<box>',
        box_end_tag='</box>',
        quad_start_tag='<quad>',
        quad_end_tag='</quad>',
        **kwargs,
    ):
        super().__init__(**kwargs)
        self.image_start_tag = image_start_tag
        self.image_end_tag = image_end_tag
        self.image_pad_tag = image_pad_tag
        self.ref_start_tag = ref_start_tag
        self.ref_end_tag = ref_end_tag
        self.box_start_tag = box_start_tag
        self.box_end_tag = box_end_tag
        self.quad_start_tag = quad_start_tag
        self.quad_end_tag = quad_end_tag
        self.IMAGE_ST = (
            ref_start_tag, ref_end_tag,
            box_start_tag, box_end_tag,
            quad_start_tag, quad_end_tag,
            image_start_tag, image_end_tag,
            image_pad_tag
        )

        self.errors = errors  # how to handle errors in decoding

        self.mergeable_ranks = _load_tiktoken_bpe(vocab_file)  # type: dict[bytes, int]
        self.special_tokens = {
            token: index
            for index, token in enumerate(
                SPECIAL_TOKENS + self.IMAGE_ST, start=len(self.mergeable_ranks)
            )
        }
        self.img_start_id = self.special_tokens[self.image_start_tag]
        self.img_end_id = self.special_tokens[self.image_end_tag]
        self.img_pad_id = self.special_tokens[self.image_pad_tag]
        self.ref_start_id = self.special_tokens[self.ref_start_tag]
        self.ref_end_id = self.special_tokens[self.ref_end_tag]
        self.box_start_id = self.special_tokens[self.box_start_tag]
        self.box_end_id = self.special_tokens[self.box_end_tag]
        self.quad_start_id = self.special_tokens[self.quad_start_tag]
        self.quad_end_id = self.special_tokens[self.quad_end_tag]

        enc = tiktoken.Encoding(
            "Qwen",
            pat_str=PAT_STR,
            mergeable_ranks=self.mergeable_ranks,
            special_tokens=self.special_tokens,
        )
        assert (
            len(self.mergeable_ranks) + len(self.special_tokens) == enc.n_vocab
        ), f"{len(self.mergeable_ranks) + len(self.special_tokens)} != {enc.n_vocab} in encoding"

        self.decoder = {
            v: k for k, v in self.mergeable_ranks.items()
        }  # type: dict[int, bytes|str]
        self.decoder.update({v: k for k, v in self.special_tokens.items()})

        self.tokenizer = enc  # type: tiktoken.Encoding

        self.eod_id = self.tokenizer.eot_token
        self.im_start_id = self.special_tokens[IMSTART]
        self.im_end_id = self.special_tokens[IMEND]

    def __getstate__(self):
        # for pickle lovers
        state = self.__dict__.copy()
        del state['tokenizer']
        return state

    def __setstate__(self, state):
        # tokenizer is not python native; don't pass it; rebuild it
        self.__dict__.update(state)
        enc = tiktoken.Encoding(
            "Qwen",
            pat_str=PAT_STR,
            mergeable_ranks=self.mergeable_ranks,
            special_tokens=self.special_tokens,
        )
        self.tokenizer = enc


    def __len__(self) -> int:
        return self.tokenizer.n_vocab

    def get_vocab(self) -> Dict[bytes, int]:
        return self.mergeable_ranks

    def convert_tokens_to_ids(
        self, tokens: Union[bytes, str, List[Union[bytes, str]]]
    ) -> List[int]:
        ids = []
        if isinstance(tokens, (str, bytes)):
            if tokens in self.special_tokens:
                return self.special_tokens[tokens]
            else:
                return self.mergeable_ranks.get(tokens)
        for token in tokens:
            if token in self.special_tokens:
                ids.append(self.special_tokens[token])
            else:
                ids.append(self.mergeable_ranks.get(token))
        return ids

    def _add_tokens(self, new_tokens: Union[List[str], List[AddedToken]], special_tokens: bool = False) -> int:
        if not special_tokens and new_tokens:
            raise ValueError('Adding regular tokens is not supported')
        for token in new_tokens:
            surface_form = token.content if isinstance(token, AddedToken) else token
            if surface_form not in SPECIAL_TOKENS + self.IMAGE_ST:
                raise ValueError('Adding unknown special tokens is not supported')
        return 0

    def save_vocabulary(self, save_directory: str, **kwargs) -> Tuple[str]:
        """
        Save only the vocabulary of the tokenizer (vocabulary).

        Returns:
            `Tuple(str)`: Paths to the files saved.
        """
        file_path = os.path.join(save_directory, "qwen.tiktoken")
        with open(file_path, "w", encoding="utf8") as w:
            for k, v in self.mergeable_ranks.items():
                line = base64.b64encode(k).decode("utf8") + " " + str(v) + "\n"
                w.write(line)
        return (file_path,)

    def tokenize(
        self,
        text: str,
        allowed_special: Union[Set, str] = "all",
        disallowed_special: Union[Collection, str] = (),
        **kwargs,
    ) -> List[Union[bytes, str]]:
        """
        Converts a string in a sequence of tokens.

        Args:
            text (`str`):
                The sequence to be encoded.
            allowed_special (`Literal["all"]` or `set`):
                The surface forms of the tokens to be encoded as special tokens in regular texts.
                Default to "all".
            disallowed_special (`Literal["all"]` or `Collection`):
                The surface forms of the tokens that should not be in regular texts and trigger errors.
                Default to an empty tuple.

            kwargs (additional keyword arguments, *optional*):
                Will be passed to the underlying model specific encode method.

        Returns:
            `List[bytes|str]`: The list of tokens.
        """
        tokens = []
        text = unicodedata.normalize("NFC", text)

        # this implementation takes a detour: text -> token id -> token surface forms
        for t in self.tokenizer.encode(
            text, allowed_special=allowed_special, disallowed_special=disallowed_special
        ):
            tokens.append(self.decoder[t])

        def _encode_imgurl(img_tokens):
            assert img_tokens[0] == self.image_start_tag and img_tokens[-1] == self.image_end_tag
            img_tokens = img_tokens[1:-1]
            img_url = b''.join(img_tokens)
            out_img_tokens = list(map(self.decoder.get, img_url))
            if len(out_img_tokens) > IMG_TOKEN_SPAN:
                raise ValueError("The content in {}..{} is too long".format(
                    self.image_start_tag, self.image_end_tag))
            out_img_tokens.extend([self.image_pad_tag] * (IMG_TOKEN_SPAN - len(out_img_tokens)))
            out_img_tokens = [self.image_start_tag] + out_img_tokens + [self.image_end_tag]
            return out_img_tokens

        return _replace_closed_tag(tokens, self.image_start_tag, self.image_end_tag, _encode_imgurl)

    def convert_tokens_to_string(self, tokens: List[Union[bytes, str]]) -> str:
        """
        Converts a sequence of tokens in a single string.
        """
        text = ""
        temp = b""
        for t in tokens:
            if isinstance(t, str):
                if temp:
                    text += temp.decode("utf-8", errors=self.errors)
                    temp = b""
                text += t
            elif isinstance(t, bytes):
                temp += t
            else:
                raise TypeError("token should only be of type types or str")
        if temp:
            text += temp.decode("utf-8", errors=self.errors)
        return text

    @property
    def vocab_size(self):
        return self.tokenizer.n_vocab

    def _convert_id_to_token(self, index: int) -> Union[bytes, str]:
        """Converts an id to a token, special tokens included"""
        if index in self.decoder:
            return self.decoder[index]
        raise ValueError("unknown ids")

    def _convert_token_to_id(self, token: Union[bytes, str]) -> int:
        """Converts a token to an id using the vocab, special tokens included"""
        if token in self.special_tokens:
            return self.special_tokens[token]
        if token in self.mergeable_ranks:
            return self.mergeable_ranks[token]
        raise ValueError("unknown token")

    def _tokenize(self, text: str, **kwargs):
        """
        Converts a string in a sequence of tokens (string), using the tokenizer. Split in words for word-based
        vocabulary or sub-words for sub-word-based vocabularies (BPE/SentencePieces/WordPieces).

        Do NOT take care of added tokens.
        """
        raise NotImplementedError

    def _decode(
        self,
        token_ids: Union[int, List[int]],
        skip_special_tokens: bool = False,
        errors: str = None,
        **kwargs,
    ) -> str:
        if isinstance(token_ids, int):
            token_ids = [token_ids]

        def _decode_imgurl(img_token_ids):
            assert img_token_ids[0] == self.img_start_id and img_token_ids[-1] == self.img_end_id
            img_token_ids = img_token_ids[1:-1]
            img_token_ids = img_token_ids[ : img_token_ids.index(self.img_pad_id)]
            img_url = bytes(img_token_ids).decode('utf-8')
            return [self.img_start_id] + self.tokenizer.encode(img_url) + [self.img_end_id]

        token_ids = _replace_closed_tag(token_ids, self.img_start_id, self.img_end_id, _decode_imgurl)

        if skip_special_tokens:
            token_ids = [i for i in token_ids if i < self.eod_id]
        return self.tokenizer.decode(token_ids, errors=errors or self.errors)

    def to_list_format(self, text: str):
        text = unicodedata.normalize("NFC", text)
        token_ids = self.tokenizer.encode(
            text, allowed_special=set(self.IMAGE_ST + (ENDOFTEXT,)))

        def _encode_vl_info(tokens):
            if len(tokens) == 0:
                return []
            if tokens[0] == self.img_start_id and tokens[-1] == self.img_end_id:
                key = 'image'
            elif tokens[0] == self.ref_start_id and tokens[-1] == self.ref_end_id:
                key = 'ref'
            elif tokens[0] == self.box_start_id and tokens[-1] == self.box_end_id:
                key = 'box'
            elif tokens[0] == self.quad_start_id and tokens[-1] == self.quad_end_id:
                key = 'quad'
            else:
                _tobytes = lambda x: x.encode('utf-8') if isinstance(x, str) else x
                return [{'text': b''.join(map(_tobytes, map(self.decoder.get, tokens))).decode('utf-8')}]
            _tobytes = lambda x: x.encode('utf-8') if isinstance(x, str) else x
            val = b''.join(map(_tobytes, map(self.decoder.get, tokens[1:-1]))).decode('utf-8')
            return [{key: val}]

        return _replace_closed_tag(
            token_ids,
            (self.img_start_id, self.ref_start_id, self.box_start_id, self.quad_start_id),
            (self.img_end_id, self.ref_end_id, self.box_end_id, self.quad_end_id),
            _encode_vl_info,
            _encode_vl_info,
        )

    def from_list_format(self, list_format: List[Dict]):
        text = ''
        num_images = 0
        for ele in list_format:
            if 'image' in ele:
                num_images += 1
                text += f'Picture {num_images}:'
                text += self.image_start_tag + ele['image'] + self.image_end_tag
                text += '\n'
            elif 'text' in ele:
                text += ele['text']
            elif 'box' in ele:
                if 'ref' in ele:
                    text += self.ref_start_tag + ele['ref'] + self.ref_end_tag
                for box in ele['box']:
                    text += self.box_start_tag + '(%d,%d),(%d,%d)' % (box[0], box[1], box[2], box[3]) + self.box_end_tag
            else:
                raise ValueError("Unsupport element: " + str(ele))
        return text

    def _fetch_latest_picture(self, response, history):
        if history is None:
            history = []
        _history = history + [(response, None)]
        for q, r in _history[::-1]:
            for ele in self.to_list_format(q)[::-1]:
                if 'image' in ele:
                    return ele['image']
        return None

    def _fetch_all_box_with_ref(self, text):
        list_format = self.to_list_format(text)
        output = []
        for i, ele in enumerate(list_format):
            if 'box' in ele:
                bbox = tuple(map(int, ele['box'].replace('(', '').replace(')', '').split(',')))
                assert len(bbox) == 4
                output.append({'box': bbox})
                if i > 0 and 'ref' in list_format[i-1]:
                    output[-1]['ref'] = list_format[i-1]['ref'].strip()
        return output

    def draw_bbox_on_latest_picture(
        self,
        response,
        history=None,
    ) -> Optional[Image.Image]:
        image = self._fetch_latest_picture(response, history)
        if image is None:
            return None
        if image.startswith("http://") or image.startswith("https://"):
            image = Image.open(requests.get(image, stream=True).raw).convert("RGB")
            h, w = image.height, image.width
        else:
            image = np.asarray(Image.open(image).convert("RGB"))
            h, w = image.shape[0], image.shape[1]
        visualizer = Visualizer(image)

        boxes = self._fetch_all_box_with_ref(response)
        if not boxes:
            return None
        color = random.choice([_ for _ in mcolors.TABLEAU_COLORS.keys()]) # init color
        for box in boxes:
            if 'ref' in box: # random new color for new refexps
                color = random.choice([_ for _ in mcolors.TABLEAU_COLORS.keys()])
            x1, y1, x2, y2 = box['box']
            x1, y1, x2, y2 = (int(x1 / 1000 * w), int(y1 / 1000 * h), int(x2 / 1000 * w), int(y2 / 1000 * h))
            visualizer.draw_box((x1, y1, x2, y2), alpha=1, edge_color=color)
            if 'ref' in box:
                visualizer.draw_text(box['ref'], (x1, y1), color=color, horizontal_alignment="left")
        return visualizer.output


import colorsys
import logging
import math
import numpy as np
import matplotlib as mpl
import matplotlib.colors as mplc
import matplotlib.figure as mplfigure
import torch
from matplotlib.backends.backend_agg import FigureCanvasAgg
from PIL import Image
import random

logger = logging.getLogger(__name__)


class VisImage:
    def __init__(self, img, scale=1.0):
        self.img = img
        self.scale = scale
        self.width, self.height = img.shape[1], img.shape[0]
        self._setup_figure(img)

    def _setup_figure(self, img):
        fig = mplfigure.Figure(frameon=False)
        self.dpi = fig.get_dpi()
        # add a small 1e-2 to avoid precision lost due to matplotlib's truncation
        # (https://github.com/matplotlib/matplotlib/issues/15363)
        fig.set_size_inches(
            (self.width * self.scale + 1e-2) / self.dpi,
            (self.height * self.scale + 1e-2) / self.dpi,
        )
        self.canvas = FigureCanvasAgg(fig)
        # self.canvas = mpl.backends.backend_cairo.FigureCanvasCairo(fig)
        ax = fig.add_axes([0.0, 0.0, 1.0, 1.0])
        ax.axis("off")
        self.fig = fig
        self.ax = ax
        self.reset_image(img)

    def reset_image(self, img):
        img = img.astype("uint8")
        self.ax.imshow(img, extent=(0, self.width, self.height, 0), interpolation="nearest")

    def save(self, filepath):
        self.fig.savefig(filepath)

    def get_image(self):
        canvas = self.canvas
        s, (width, height) = canvas.print_to_buffer()

        buffer = np.frombuffer(s, dtype="uint8")

        img_rgba = buffer.reshape(height, width, 4)
        rgb, alpha = np.split(img_rgba, [3], axis=2)
        return rgb.astype("uint8")


class Visualizer:
    def __init__(self, img_rgb, metadata=None, scale=1.0):
        self.img = np.asarray(img_rgb).clip(0, 255).astype(np.uint8)
        self.font_path = FONT_PATH
        self.output = VisImage(self.img, scale=scale)
        self.cpu_device = torch.device("cpu")

        # too small texts are useless, therefore clamp to 14
        self._default_font_size = max(
            np.sqrt(self.output.height * self.output.width) // 30, 15 // scale
        )

    def draw_text(
        self,
        text,
        position,
        *,
        font_size=None,
        color="g",
        horizontal_alignment="center",
        rotation=0,
    ):
        if not font_size:
            font_size = self._default_font_size

        # since the text background is dark, we don't want the text to be dark
        color = np.maximum(list(mplc.to_rgb(color)), 0.2)
        color[np.argmax(color)] = max(0.8, np.max(color))

        x, y = position
        self.output.ax.text(
            x,
            y,
            text,
            size=font_size * self.output.scale,
            fontproperties=FontProperties(fname=self.font_path),
            bbox={"facecolor": "black", "alpha": 0.8, "pad": 0.7, "edgecolor": "none"},
            verticalalignment="top",
            horizontalalignment=horizontal_alignment,
            color=color,
            zorder=10,
            rotation=rotation,
        )
        return self.output

    def draw_box(self, box_coord, alpha=0.5, edge_color="g", line_style="-"):
        
        x0, y0, x1, y1 = box_coord
        width = x1 - x0
        height = y1 - y0

        linewidth = max(self._default_font_size / 4, 1)

        self.output.ax.add_patch(
            mpl.patches.Rectangle(
                (x0, y0),
                width,
                height,
                fill=False,
                edgecolor=edge_color,
                linewidth=linewidth * self.output.scale,
                alpha=alpha,
                linestyle=line_style,
            )
        )
        return self.output

    def get_output(self):
        
        return self.output