SDL_MixAudio

Use this function to mix audio data.

Syntax

void SDL_MixAudio(Uint8*       dst, 
                  const Uint8* src,
                  Uint32       len, 
                  int          volume)

Function Parameters

Code Examples

You can add your code example here

Remarks

This takes two audio buffers of len bytes each of the playing audio format and mixes them, performing addition, volume adjustment, and overflow clipping.

Note that this does not change hardware volume.

This is provided for convenience -- you can mix your own audio data.

Do not use this function for mixing together more than two streams of sample data. The output from repeated application of this function may be distorted by clipping, because there is no accumulator with greater range than the input (not to mention this being an inefficient way of doing it). Use mixing functions from SDL_mixer, OpenAL, or write your own mixer instead.

It is a common misconception that this function is required to write audiodata to an outputstream in the audio-callback like:

void audio_callback(void *udata, Uint8 *stream, int len)
{
    SDL_MixAudio(stream, audio_pos, len, SDL_MIX_MAXVOLUME);
}

Although this works, for a single channel it's just as good as writing the audiodata directly to stream; that is if you don't need the volume adjustment.

Related Functions

• SDL_MixAudioFormat