File size: 5,291 Bytes
2c924d3
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
# Copyright (c) OpenMMLab. All rights reserved.
import os
import os.path as osp
import subprocess
import tempfile

from annotator.uniformer.mmcv.utils import requires_executable


@requires_executable('ffmpeg')
def convert_video(in_file,
                  out_file,
                  print_cmd=False,
                  pre_options='',
                  **kwargs):
    """Convert a video with ffmpeg.

    This provides a general api to ffmpeg, the executed command is::

        `ffmpeg -y <pre_options> -i <in_file> <options> <out_file>`

    Options(kwargs) are mapped to ffmpeg commands with the following rules:

    - key=val: "-key val"
    - key=True: "-key"
    - key=False: ""

    Args:
        in_file (str): Input video filename.
        out_file (str): Output video filename.
        pre_options (str): Options appears before "-i <in_file>".
        print_cmd (bool): Whether to print the final ffmpeg command.
    """
    options = []
    for k, v in kwargs.items():
        if isinstance(v, bool):
            if v:
                options.append(f'-{k}')
        elif k == 'log_level':
            assert v in [
                'quiet', 'panic', 'fatal', 'error', 'warning', 'info',
                'verbose', 'debug', 'trace'
            ]
            options.append(f'-loglevel {v}')
        else:
            options.append(f'-{k} {v}')
    cmd = f'ffmpeg -y {pre_options} -i {in_file} {" ".join(options)} ' \
          f'{out_file}'
    if print_cmd:
        print(cmd)
    subprocess.call(cmd, shell=True)


@requires_executable('ffmpeg')
def resize_video(in_file,
                 out_file,
                 size=None,
                 ratio=None,
                 keep_ar=False,
                 log_level='info',
                 print_cmd=False):
    """Resize a video.

    Args:
        in_file (str): Input video filename.
        out_file (str): Output video filename.
        size (tuple): Expected size (w, h), eg, (320, 240) or (320, -1).
        ratio (tuple or float): Expected resize ratio, (2, 0.5) means
            (w*2, h*0.5).
        keep_ar (bool): Whether to keep original aspect ratio.
        log_level (str): Logging level of ffmpeg.
        print_cmd (bool): Whether to print the final ffmpeg command.
    """
    if size is None and ratio is None:
        raise ValueError('expected size or ratio must be specified')
    if size is not None and ratio is not None:
        raise ValueError('size and ratio cannot be specified at the same time')
    options = {'log_level': log_level}
    if size:
        if not keep_ar:
            options['vf'] = f'scale={size[0]}:{size[1]}'
        else:
            options['vf'] = f'scale=w={size[0]}:h={size[1]}:' \
                            'force_original_aspect_ratio=decrease'
    else:
        if not isinstance(ratio, tuple):
            ratio = (ratio, ratio)
        options['vf'] = f'scale="trunc(iw*{ratio[0]}):trunc(ih*{ratio[1]})"'
    convert_video(in_file, out_file, print_cmd, **options)


@requires_executable('ffmpeg')
def cut_video(in_file,
              out_file,
              start=None,
              end=None,
              vcodec=None,
              acodec=None,
              log_level='info',
              print_cmd=False):
    """Cut a clip from a video.

    Args:
        in_file (str): Input video filename.
        out_file (str): Output video filename.
        start (None or float): Start time (in seconds).
        end (None or float): End time (in seconds).
        vcodec (None or str): Output video codec, None for unchanged.
        acodec (None or str): Output audio codec, None for unchanged.
        log_level (str): Logging level of ffmpeg.
        print_cmd (bool): Whether to print the final ffmpeg command.
    """
    options = {'log_level': log_level}
    if vcodec is None:
        options['vcodec'] = 'copy'
    if acodec is None:
        options['acodec'] = 'copy'
    if start:
        options['ss'] = start
    else:
        start = 0
    if end:
        options['t'] = end - start
    convert_video(in_file, out_file, print_cmd, **options)


@requires_executable('ffmpeg')
def concat_video(video_list,
                 out_file,
                 vcodec=None,
                 acodec=None,
                 log_level='info',
                 print_cmd=False):
    """Concatenate multiple videos into a single one.

    Args:
        video_list (list): A list of video filenames
        out_file (str): Output video filename
        vcodec (None or str): Output video codec, None for unchanged
        acodec (None or str): Output audio codec, None for unchanged
        log_level (str): Logging level of ffmpeg.
        print_cmd (bool): Whether to print the final ffmpeg command.
    """
    tmp_filehandler, tmp_filename = tempfile.mkstemp(suffix='.txt', text=True)
    with open(tmp_filename, 'w') as f:
        for filename in video_list:
            f.write(f'file {osp.abspath(filename)}\n')
    options = {'log_level': log_level}
    if vcodec is None:
        options['vcodec'] = 'copy'
    if acodec is None:
        options['acodec'] = 'copy'
    convert_video(
        tmp_filename,
        out_file,
        print_cmd,
        pre_options='-f concat -safe 0',
        **options)
    os.close(tmp_filehandler)
    os.remove(tmp_filename)