Using ffprobe to check audio-only files

问题:

Is there an ffprobe command I can run to see if an mov file that I have is audio-only or contains video as well? I have various mov files, some of which are audio dubs and some of which are full videos.

回答1:

You can output stream information in JSON or XML:

ffprobe -show_streams -print_format json input.mov

You'll get an array of streams with a codec_type attribute with values like audio, video etc.

回答2:

To output the codec_type

ffprobe -loglevel error -show_entries stream=codec_type -of default=nw=1 input.foo

Example result:

codec_type=video
codec_type=audio

If you have multiple audio or video streams the output will show multiple video or audio entries.

---

Same as above but output just the values

ffprobe -loglevel error -show_entries stream=codec_type -of default=nw=1=nk=1 input.foo

or:

ffprobe -loglevel error -show_entries stream=codec_type -of csv=p=0 input.foo

Example result:

video
audio

---

To include the stream index

ffprobe -loglevel error -show_entries stream=index,codec_type -of csv=p=0 input.foo

Example result:

0,video
1,audio

In this example the video is the first stream and the audio is the second stream which is the norm but not always the case.

---

Output nothing if there is no audio

ffprobe -loglevel error -select_streams a -show_entries stream=codec_type -of csv=p=0 input.foo

Example result for input with audio:

audio

If the input does not have audio then there will be no output (null output) which could be useful for scripted usage.

---

Other output formats

If you want different output formatting (json, ini, flat, csv, xml) see FFprobe Documentation: Writers.

回答3:

One quick way to do this is to check if the word 'Video' is in the output. Here's an example:

>>> cmd = shlex.split('%s -i %s' % (FFPROBE, video_path))
>>> p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
>>> output = p.communicate()[1]
>>> 'Video' in output
True

I tried this for a few different files and it seemed to work on the ones I tried, though I'm sure there's a much better solution.

回答4:

To find out programmatically if a video file has audio, use avformat_open_input() as shown here below - if audio_index is bigger or equal to zero, then the video file has audio.

if (avformat_open_input(&pFormatCtx, filename, nullptr, nullptr) != 0) {
    fprintf(stderr, "Couldn't open video file!\n");
    return -1;
}

if (avformat_find_stream_info(pFormatCtx, nullptr) < 0) {
    fprintf(stderr, "Couldn't find stream information!\n");
    return -1;
}

av_dump_format(pFormatCtx, 0, videoState->filename, 0);

for (i = 0; i < pFormatCtx->nb_streams; i++) {

    if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO && video_index < 0)
        video_index = i;

    if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_AUDIO && audio_index < 0)
        audio_index = i;
}