【发布时间】：2020-11-23 20:36:30
【问题描述】：
我有一个带有.mov 容器的 ProRes422 文件：FINAL.mov。我想将音轨保存到一个新文件中（没有编码或任何东西，只需将其保存）。在 QuickTime 中有一个选项可以保存“仅音频”--
在 ffmpeg 中执行此操作的等效方法是什么？从基础研究来看，似乎是这样的：
$ ffmpeg \
-i FINAL.mov \
-vn # remove video? \
?? # keep audio \
MYAUDIO_FINAL.mov
$ ffmpeg -i 给出：
Guessed Channel Layout for Input Stream #0.1 : stereo
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'FINAL.mov':
Metadata:
major_brand : qt
minor_version : 537199360
compatible_brands: qt
creation_time : 2016-01-11T19:23:10.000000Z
com.apple.finalcutstudio.media.uuid: CE6F1278-8982-4B98-9E46-AE7C329436EF
com.apple.quicktime.player.movie.audio.gain: 1.000000
com.apple.quicktime.player.movie.audio.treble: 0.000000
com.apple.quicktime.player.movie.audio.bass: 0.000000
com.apple.quicktime.player.movie.audio.balance: 0.000000
com.apple.quicktime.player.movie.audio.pitchshift: 0.000000
com.apple.quicktime.player.movie.audio.mute:
com.apple.quicktime.player.movie.visual.brightness: 0.000000
com.apple.quicktime.player.movie.visual.color: 1.000000
com.apple.quicktime.player.movie.visual.tint: 0.000000
com.apple.quicktime.player.movie.visual.contrast: 1.000000
com.apple.quicktime.player.version: 7.6.6 (7.6.6)
com.apple.quicktime.version: 7.7.3 (2826.24) 0x7738000 (Mac OS X, 10.9.5, 13F34)
Duration: 00:01:59.58, start: 0.000000, bitrate: 154872 kb/s
Stream #0:0(eng): Video: prores (apch / 0x68637061), yuv422p10le(bt709, progressive), 1920x1080, 153307 kb/s, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 23976 tbn, 23976 tbc (default)
Metadata:
creation_time : 2016-01-11T19:23:10.000000Z
handler_name : Apple Alias Data Handler
encoder : Apple ProRes 422 (HQ)
Stream #0:1(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, stereo, s16, 1536 kb/s (default)
Metadata:
creation_time : 2016-01-11T19:23:10.000000Z
handler_name : Apple Alias Data Handler
还有一个带有 8 通道音频的文件：
Duration: 01:10:12.00, start: 0.000000, bitrate: 173231 kb/s
Stream #0:0(eng): Video: prores (apch / 0x68637061), yuv422p10le(bt709, progressive), 1920x1080, 164007 kb/s, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 24k tbn, 24k tbc (default)
Metadata:
handler_name : Apple Alias Data 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:
handler_name : Apple Alias Data Handler
Stream #0:2(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (FR), s32 (24 bit), 1152 kb/s (default)
Metadata:
handler_name : Apple Alias Data Handler
Stream #0:3(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, mono, s32 (24 bit), 1152 kb/s (default)
Metadata:
handler_name : Apple Alias Data Handler
Stream #0:4(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (LFE), s32 (24 bit), 1152 kb/s (default)
Metadata:
handler_name : Apple Alias Data Handler
Stream #0:5(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (BL), s32 (24 bit), 1152 kb/s (default)
Metadata:
handler_name : Apple Alias Data Handler
Stream #0:6(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (BR), s32 (24 bit), 1152 kb/s (default)
Metadata:
handler_name : Apple Alias Data Handler
Stream #0:7(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (DL), s32 (24 bit), 1152 kb/s (default)
Metadata:
handler_name : Apple Alias Data Handler
Stream #0:8(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels (DR), s32 (24 bit), 1152 kb/s (default)
Metadata:
handler_name : Apple Alias Data Handler
At least one output file must be specified
【问题讨论】：
-
@llogan 是的，它应该保持原样。换句话说，5.1 音轨应该保持 5.1（但 mov 不会自动这样做吗？）。
-
@llogan 我想我能从技术上回答这个问题的唯一方法是，如果音频再次“交换”到视频中，当完整的 mov 文件被 md5 编辑时，它应该具有相同的校验和。
-
@llogan 已更新...虽然会有各种文件输入，但都是
.mov。