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I try to play a mov-file with the following stream informations:

Video:
Codec: Apple ProRes
Resolution: 1280x736
Fps: 50
Audio:
Codec: PCM S24 LE
Sampling rate: 48000 Hz
Bits per sample: 24
Bitrate: 12288 kB/s

The problem is that VLC plays the video, but no audio. How can I enable that?

If sudo aplay -l was meant:

    **** List of PLAYBACK Hardware Devices ****
Home directory not accessible: Permission denied
card 0: PCH [HDA Intel PCH], device 0: ALC269VB Analog [ALC269VB Analog]
  Subdevices: 0/1
  Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 1: ALC269VB Digital [ALC269VB Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

When trying the command shown in the answer:

avconv -i $myfile.mov -c:a flac -c:v copy $myfile.mkv

I get 

avconv version 9.18-6:9.18-0ubuntu0.14.04.1+fdkaac, Copyright (c) 2000-2014 the Libav developers
  built on Apr 10 2015 23:18:58 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/media/roland/Hitachi/Capture0000.mov':
  Metadata:
    creation_time   : 2000-01-20 15:56:31
  Duration: 00:48:31.32, start: 0.000000, bitrate: 102914 kb/s
    Stream #0.0(eng): Data: tmcd / 0x64636D74
    Metadata:
      creation_time   : 2000-01-20 15:56:31
    Stream #0.1(eng): Video: prores, yuv422p10le, 1280x720, 84447 kb/s, PAR 1:1 DAR 16:9, 50 fps, 50 tbr, 5k tbn
    Metadata:
      creation_time   : 2000-01-20 15:56:31
    Stream #0.2(eng): Audio: pcm_s24le, 48000 Hz, 16 channels, s32, 18432 kb/s
    Metadata:
      creation_time   : 2000-01-20 15:56:31
[abuffer @ 0x14f2b60] Invalid channel layout 0x0.
Error opening filters!
arc_lupus
  • 202

1 Answers1

3

My guess is that PCM S24 LE 48kHz/24Bit is so uncommon that VLC doesn't expect nor support it in a media file yet. PCM is also very inefficient, lossless codecs like FLAC provide the same quality. Using libav/ffmpeg you can copy the video and convert the audio stream to FLAC, which should give you working audio playback:

avconv -i $myfile.mov -c:a flac -c:v copy $myfile.mkv

I have seen (L)PCM 24Bit audio on concert Blurays before, audio actually does play but has a very loud signal on top of the actual audio stream – which could be a format parsing error.

I chose the MKV container as an output format here because it has no format restrictions that I know of and is very extendable, pairing MOV or MP4 with FLAC may not work.

One last note, who ever made this file should check if that is really the desired result. 50fps is fine and may indicate that this is PAL or some other non-NTSC content, but 1280x736 is 16 pixels above 720p (1280x720), which may be fine with the codec or encoder but not optimal or even incompatible with typical playback devices.

The third stream was unexpected (and you didn't say that you pull raw material from what appears to be a camera), we can probably map to just include video and audio in the output and leave out what appears to be time code data.

avconv -i $myfile.mov -map 0:1 -c:v copy -map 0:2 -c:a flac $myfile.mkv

A similar question on SuperUser: ffmpeg stripping out third stream not working and also related How drop an audio stream using avconv?

It's probably also relevant to note that we have a site for video production.

Community
  • 1
LiveWireBT
  • 28,763
  • Thanks, but how is the new size of the file? The same size, smaller, bigger? – arc_lupus Dec 06 '15 at 15:50
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    @arc_lupus PCM is uncompressed, FLAC is lossless compression. If no modification is made to sampling rate or bit depth then FLAC is typically 1/2 to 3/4 smaller. FLAC may however not support 24Bit and switch to 32Bit. I just converted a 578 MB PCM S24 BE stream to 32Bit FLAC and the result was still 100 MB smaller. – LiveWireBT Dec 06 '15 at 16:02
  • When testing the command shown above, I get the output I added in the OP... – arc_lupus Dec 06 '15 at 20:47
  • @arc_lupus Thanks I edited my answer, but please also include the actual command you ran next time. Hope this solves your problem now. – LiveWireBT Dec 06 '15 at 21:58
  • Well, I did not know that before I ran the command... – arc_lupus Dec 06 '15 at 22:22