Repository: yt-dlp/yt-dlp
File: yt_dlp/extractor/tiktok.py (Python)

Code before:
                'filesize': int_or_none(addr.get('data_size')),
                'ext': 'mp4',
                'acodec': 'aac',
                'source_preference': -2 if 'aweme/v1' in url else -1,  # Downloads from API might get blocked
                **add_meta, **parsed_meta
            } for url in addr.get('url_list') or []]

        # Hack: Add direct video links first to prioritize them when removing duplicate formats
        formats = []
        if video_info.get('play_addr'):
            formats.extend(extract_addr(video_info['play_addr'], {
                'format_id': 'play_addr',
                'format_note': 'Direct video',
                'vcodec': 'h265' if traverse_obj(
                    video_info, 'is_bytevc1', 'is_h265') else 'h264',  # Always h264?
                'width': video_info.get('width'),
                'height': video_info.get('height'),
            }))
        if video_info.get('download_addr'):
            formats.extend(extract_addr(video_info['download_addr'], {
                'format_id': 'download_addr',
                'format_note': 'Download video%s' % (', watermarked' if video_info.get('has_watermark') else ''),
                'vcodec': 'h264',
                'width': video_info.get('width'),
                'height': video_info.get('height'),
                'preference': -2 if video_info.get('has_watermark') else -1,
            }))
        if video_info.get('play_addr_h264'):
            formats.extend(extract_addr(video_info['play_addr_h264'], {
                'format_id': 'play_addr_h264',
                'format_note': 'Direct video',
                'vcodec': 'h264',
            }))
        if video_info.get('play_addr_bytevc1'):
            formats.extend(extract_addr(video_info['play_addr_bytevc1'], {
                'format_id': 'play_addr_bytevc1',
                'format_note': 'Direct video',
                'vcodec': 'h265',
            }))

        for bitrate in video_info.get('bit_rate', []):
            if bitrate.get('play_addr'):
                formats.extend(extract_addr(bitrate['play_addr'], {
                    'format_id': bitrate.get('gear_name'),
                    'format_note': 'Playback video',
                    'tbr': try_get(bitrate, lambda x: x['bit_rate'] / 1000),
                    'vcodec': 'h265' if traverse_obj(
                        bitrate, 'is_bytevc1', 'is_h265') else 'h264',
                }))

        self._remove_duplicate_formats(formats)

Review comment (suggestion):
```
                    * preference Order number of this format. If this field is
                                 present and not None, the formats get sorted
                                 by this field, regardless of all other values.
```
Are you sure this is what you want? The priority of `preference` cannot be adjusted using `_sort_formats`. I believe this should in fact be `source_preference` here

Code after:
                'acodec': 'aac',
                'source_preference': -2 if 'aweme/v1' in url else -1,  # Downloads from API might get blocked
                **add_meta, **parsed_meta,
                'format_note': ' '.join(filter(None, (
                    add_meta.get('format_note'), '(API)' if 'aweme/v1' in url else '')))
            } for url in addr.get('url_list') or []]

        # Hack: Add direct video links first to prioritize them when removing duplicate formats
        formats = []
        if video_info.get('play_addr'):
            formats.extend(extract_addr(video_info['play_addr'], {
                'format_id': 'play_addr',
                'format_note': 'Direct video',
                'vcodec': 'h265' if traverse_obj(
                    video_info, 'is_bytevc1', 'is_h265') else 'h264',  # Always h264?
                'width': video_info.get('width'),
                'height': video_info.get('height'),
            }))
        if video_info.get('download_addr'):
            formats.extend(extract_addr(video_info['download_addr'], {
                'format_id': 'download_addr',
                'format_note': 'Download video%s' % (', watermarked' if video_info.get('has_watermark') else ''),
                'vcodec': 'h264',
                'width': video_info.get('width'),
                'height': video_info.get('height'),
                'preference': -2 if video_info.get('has_watermark') else -1,
            }))
        if video_info.get('play_addr_h264'):
            formats.extend(extract_addr(video_info['play_addr_h264'], {
                'format_id': 'play_addr_h264',
                'format_note': 'Direct video',
                'vcodec': 'h264',
            }))
        if video_info.get('play_addr_bytevc1'):
            formats.extend(extract_addr(video_info['play_addr_bytevc1'], {
                'format_id': 'play_addr_bytevc1',
                'format_note': 'Direct video',
                'vcodec': 'h265',
            }))

        for bitrate in video_info.get('bit_rate', []):
            if bitrate.get('play_addr'):
                formats.extend(extract_addr(bitrate['play_addr'], {
                    'format_id': bitrate.get('gear_name'),
                    'format_note': 'Playback video',
                    'tbr': try_get(bitrate, lambda x: x['bit_rate'] / 1000),
                    'vcodec': 'h265' if traverse_obj(
                        bitrate, 'is_bytevc1', 'is_h265') else 'h264',
                }))

        self._remove_duplicate_formats(formats)