ffmpeg - 从具有单声道和缩混的文件中提取具有 5.1 音频的 PRORES 视频

Question

我正在尝试从具有以下音轨布局的 Prores 中提取只有 5.1 音频的 prores 视频。如何使用 FFmpeg 库来做到这一点？
我无法从下面的 ffmpeg 库规范中找出要使用的命令
https://trac.ffmpeg.org/wiki/AudioChannelManipulation#a2monostereo
所需的输出 PRORES 包含以下轨道布局

轨道 0 - 视频(src 流 #0:0)

轨道 1 - FL (src Stream #0:1)

轨道 2 - FR (src Stream #0:2)

轨道 3 - FC (src Stream #0:3)

轨道 4 - LFE (src Stream #0:4)

轨道 5 - BL (src Stream #0:5)

轨道 6 - BR (src Stream #0:6)

轨道 7 - tmcd (src Stream #0:8)

以下是源视频/音频轨道布局

Stream #0:0(eng): Video: prores (HQ) (apch / 0x68637061), yuv422p10le(tv, bt709, progressive), 1920x1080, 171944 kb/s, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 23976 tbn, 23976 tbc (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Video Media Handler
      encoder         : Apple ProRes 422 HQ
    Stream #0:1(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (FL), s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Sound Media Handler
    Stream #0:2(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (FR), s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Sound Media Handler
    Stream #0:3(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, mono, s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Sound Media Handler
    Stream #0:4(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (LFE), s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Sound Media Handler
    Stream #0:5(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (BL), s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Sound Media Handler
    Stream #0:6(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (BR), s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Sound Media Handler
    Stream #0:7(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, downmix, s32 (24 bit), 2304 kb/s (default)
    Metadata:
      creation_time   : 2019-05-21T01:26:51.000000Z
      handler_name    : Apple Sound Media Handler
    Stream #0:8(eng): Data: none (tmcd / 0x64636D74) (default)
    Metadata:
      creation_time   : 2020-03-17T19:58:52.000000Z
      handler_name    : Time Code Media Handler
      reel_name       :
      timecode        : 00:00:00:00

Answer 1

使用 channelmap筛选:

ffmpeg -i input.mov -filter_complex "[0:a:0]channelmap=channel_layout=FL[FL];[0:a:1]channelmap=channel_layout=FR[FR];[0:a:2]channelmap=channel_layout=FC[FC];[0:a:3]channelmap=channel_layout=LFE[LFE];[0:a:4]channelmap=channel_layout=BL[BL];[0:a:5]channelmap=channel_layout=BR[BR]" -map 0:v -map "[FL]" -map "[FR]" -map "[FC]" -map "[LFE]" -map "[BL]" -map "[BR]" -map d -c copy -c:a pcm_s24le output.mov