[FFmpeg-devel] [PATCH] Get rid of SAMPLE_FMT_S24

Baptiste Coudurier baptiste.coudurier
Sun Nov 18 16:53:50 CET 2007

Michael Niedermayer a ?crit :
> On Sun, Nov 18, 2007 at 02:35:17PM +0100, Baptiste Coudurier wrote:
>> Hi
>> Andreas ?man a ?crit :
>>> hi,
>>> see $subj
>> Some codecs support 24 bit (alac, flac, aes3, dvd) samples, decoders 
>> should output what is stored, ideally, so I don't see why SAMPLE_FMT_S24 
>> should be dropped.
> there are no 24bit ints stored, what is stored are various vlc codes
> outputing them as 32bit is faster and more natural than 24bit
> also working with 32bit is a lot easier than 24bit, so few if any filters
> would support 24bit ...

There are 24 bits ints stored, in dvd pcm and aes 3 at least.

You are IMHO messing up sample format and stored format.
SAMPLE_FMT_S24 depicts the sample value range is using 24 bits.

I still don't see why SAMPLE_FMT_S24 should be dropped.

In contrary I think a better mechanism should be added, like 
WAVEFORMATEXTENSIBLE does, if you want to tell application that sample 
is on 24 bits but stored on 32 bits.

Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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