[FFmpeg-devel] Matroska and PCM variants, error in encoding?
pb at das-werkstatt.com
Tue Aug 4 09:45:59 CEST 2015
On 08/03/2015 01:50 PM, Ronald S. Bultje wrote:
> Just different offsets and ranges. Unsigned, n bits (e.g. u8) is in the
> range [0,2^^n> (e.g. for u8, the range is [0,255] or [0,256>), where
> silence is 2^^n-1, e.g. 0x80 (128) for u8. Signed is in the range
> [-2^^n-1,2^^n-1> (e.g. s16, the most typical variant, is [-32768,32767].
> Float is in the range [-1.0, 1.0]. In both cases, 0, is silence.
> We have various formats so we can represent exactly what's in a file or
> output by any one particular decoder without having to convert the internal
> representation into some intermediate format.
Thanks for that detailed explanation.
I've never used DPCM with FFmpeg, but after Andreas' question I looked
it up, and found some documentation, and wanted to clear things up.
Am I correct with the following conclusion:
- acodec "pcm_*" is always linear PCM 
- DPCM would be prefixed with "adpcm_*" (and some exceptions, like
"interplay_dpcm", etc )
Thanks in advance,
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