[FFmpeg-devel] Matroska and PCM variants, error in encoding?
Paul B Mahol
onemda at gmail.com
Mon Aug 3 13:44:25 CEST 2015
On 8/3/15, Romeyke, Andreas <Andreas.Romeyke at slub-dresden.de> wrote:
> Dear FFMPEG-developer,
> in case of digital preservation I want to convert/normalize videos to files
> with Matroska-Container, FFV1 video- and wave-PCM audiocodec.
> I am using this commandline:
> ffmpeg -i inputvideo.webm -c:v ffv1 -level 3 -g 1 -coder 1 -context 1
> -slices 16 -slicecrc 1 -report -c:a pcm_s32le -y outputvideo.mkv
> This line works fine, but with "-c:a pcm_u24le" I got the error message:
> "[matroska @ 0x1a0adc0] No wav codec tag found for codec pcm_u32le"
> Could you explain me, what was going wrong?
Matroska does not support such audio codec.
> And secondly, could you explain the difference between the various
> PCM-encodings? My assumpation was, that
> * the unsigned variant are "linear PCM", because there are only positive
> quantization levels
> * the signed variant are "linear differential PCM"
> * and the float variants are A/u - weighted PCM?
> Or I am totally wrong with this interpretation? Please, could you link me
> to an explanation?
There is no point to use unsigned PCM use signed codec you will not
> Thanks in advance
> Mit freundlichen Gru:ssen
> With best regards,
> Andreas Romeyke
> project member "long-term preservation"
> Saxon State- and University Library Dresden (SLUB)
> Department 2 (IT), Division 2.3 (network and data security)
> Zellescher Weg 18 | 01069 Dresden
> phone: +49 351 4677 216
> E-Mail: Andreas.Romeyke at slub-dresden.de
> http://www.slub-dresden.de/ | @slubdresden
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
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