8 bit rate conversion replacement for the wretched SDL one

SDL Development
1

Hello,

I am looking for an audio conversion replacement for wretched SDL 8 bit conversion.

While SDL is great this has become a problem as we need to convert 11025hz mono channels to be mixed to a master sample rate using SDL_mixer. The default rate conversion sounds horrible at this time.

While sox can do the conversion the libst it’s supposed to become is not mature yet and this should be a resonably simple conversion (though not as simple as SDL’s) and we’re
willing to preconvert this prior to feeding it to SDL/SDL_mixer.

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2

Hello,

I am looking for an audio conversion replacement for wretched SDL 8 bit
conversion.

(The main problem with SDL’s conversion is that it’s a bit messy to get
around the buffer size restrictions in there…)

While SDL is great this has become a problem as we need to convert
11025hz mono channels to be mixed to a master sample rate using
SDL_mixer. The default rate conversion sounds horrible at this time.

While sox can do the conversion the libst it’s supposed to become is
not mature yet and this should be a resonably simple conversion (though
not as simple as SDL’s) and we’re willing to preconvert this prior to
feeding it to SDL/SDL_mixer.

Well, what kind of quality do you need?

You’ll find a very primitive nearest-sample resampler in the sound engine
of Kobo Deluxe, and it doesn’t sound all that bad when converting the 8
kHz stereo 8 bit sfx to 44.1 or 48 kHz - but it’s very low quality
compared to anything you’d find in a serious music/audio application.

Linear interpolation is easy to do and sounds quite a bit better in most
cases - will probably do for games in general.

//David Olofson — Programmer, Reologica Instruments AB

.- M A I A -------------------------------------------------.
| Multimedia Application Integration Architecture |
| A Free/Open Source Plugin API for Professional Multimedia |
----------------------------> http://www.linuxdj.com/maia -' .- David Olofson -------------------------------------------. | Audio Hacker - Open Source Advocate - Singer - Songwriter |-------------------------------------> http://olofson.net -'On Sunday 09 December 2001 08:06, J. Caldwell wrote: