[RFC] Extended Audio Converters

Hi,

I extended the AudioCvt function in respect to sample rate conversion.
This should improve sound quality. Please regard it as a design draft

  • which compiles - but obiously didn’t work.
    There is one major function missing: setupVarFilter, which fills the
    filter coefficients depending on the conversion ratio.
    I didn’t know about many application, which utilize the AudioCvt,
    so please tell me if i miss a design goal (is 4channel audio relevant?)
    or if you consider the additional sound quality important/intresting.

Frank

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I extended the AudioCvt function in respect to sample rate conversion.
This should improve sound quality. Please regard it as a design draft

  • which compiles - but obiously didn’t work.
    There is one major function missing: setupVarFilter, which fills the
    filter coefficients depending on the conversion ratio.
    I didn’t know about many application, which utilize the AudioCvt,
    so please tell me if i miss a design goal (is 4channel audio relevant?)
    or if you consider the additional sound quality important/intresting.

I believe that there are some places internal to SDL that are hardcoded to
expect 1 (mono) or 2 (stereo) channels, and most of its audio output
targets wouldn’t know what to do with > 2 channels.

I am interested in seeing better sample rate conversion, since SDL_sound
(http://icculus.org/SDL_sound/) can make heavy use of it in certain
circumstances.

–ryan.