Reply by ryujin_ssdt November 1, 20072007-11-01
Look at ffmpeg source code, there are at least 5 different ADPCM
implementations to choose from including the CCITT G.726.



>dbell wrote: > >> What I am looking for is the algorithm description including data >> packing format for >> >> WAVE_FORMAT_MEDIASPACE_ADPCM (0x0012) > >All I can offer you is good luck as that is one of the many ADPCM >algorithms I have never seen documentation or code for. > >However, if you have a PCM -> WAVE_FORMAT_MEDIASPACE_ADPCM encoder >and a WAVE_FORMAT_MEDIASPACE_ADPCM -> PCM decoder then reverse >engineering the decoder is usually pretty easy. I'd even offer to >do it for you for a fee :-). > >Erik >-- >----------------------------------------------------------------- >Erik de Castro Lopo >----------------------------------------------------------------- >C++: The power, elegance and simplicity of a hand grenade. >
Reply by Erik de Castro Lopo October 30, 20072007-10-30
dbell wrote:

> What I am looking for is the algorithm description including data > packing format for > > WAVE_FORMAT_MEDIASPACE_ADPCM (0x0012)
All I can offer you is good luck as that is one of the many ADPCM algorithms I have never seen documentation or code for. However, if you have a PCM -> WAVE_FORMAT_MEDIASPACE_ADPCM encoder and a WAVE_FORMAT_MEDIASPACE_ADPCM -> PCM decoder then reverse engineering the decoder is usually pretty easy. I'd even offer to do it for you for a fee :-). Erik -- ----------------------------------------------------------------- Erik de Castro Lopo ----------------------------------------------------------------- C++: The power, elegance and simplicity of a hand grenade.
Reply by dbell October 29, 20072007-10-29
Hi Erik,

What I am looking for is the algorithm description including data
packing format for

WAVE_FORMAT_MEDIASPACE_ADPCM (0x0012)

Any guidance would be appreciated.

Thanks,

Dirk


On Oct 29, 6:11 pm, Erik de Castro Lopo <er...@mega-nerd.com> wrote:
> dbell wrote: > > Hello Everybody, > > > Does anyone know where to find a detailed algorithm description for > > Wav file compatible ADPCM? > > ADPCM is a class of algorithms, not a particular algorithm, > > There are at least 20 different ADPCM algorithms which can > be used in a WAV file container. Which one in particular do > you mean? > > Erik > -- > ----------------------------------------------------------------- > Erik de Castro Lopo > -----------------------------------------------------------------http://en.wikipedia.org/wiki/Why_I_Am_Not_a_Christianhttp://en.wikipedia.org/wiki/Why_I_Am_Not_a_Muslimhttp://en.wikipedia.org/wiki/Strong_atheism
Reply by Erik de Castro Lopo October 29, 20072007-10-29
dbell wrote:

> Hello Everybody, > > Does anyone know where to find a detailed algorithm description for > Wav file compatible ADPCM?
ADPCM is a class of algorithms, not a particular algorithm, There are at least 20 different ADPCM algorithms which can be used in a WAV file container. Which one in particular do you mean? Erik -- ----------------------------------------------------------------- Erik de Castro Lopo ----------------------------------------------------------------- http://en.wikipedia.org/wiki/Why_I_Am_Not_a_Christian http://en.wikipedia.org/wiki/Why_I_Am_Not_a_Muslim http://en.wikipedia.org/wiki/Strong_atheism
Reply by dbell October 29, 20072007-10-29
Hello Everybody,

Does anyone know where to find a detailed algorithm description for
Wav file compatible ADPCM?

Thanks,

Dirk