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SDL_AudioSpec(3)	       SDL API Reference	      SDL_AudioSpec(3)


SDL_AudioSpec - Audio Specification Structure


typedef struct{ int freq; Uint16 format; Uint8 channels; Uint8 silence; Uint16 samples; Uint32 size; void (*callback)(void *userdata, Uint8 *stream, int len); void *userdata; } SDL_AudioSpec;


freq Audio frequency in samples per second format Audio data format channels Number of channels: 1 mono, 2 stereo silence Audio buffer silence value (calculated) samples Audio buffer size in samples size Audio buffer size in bytes (calculated) callback(..) Callback function for filling the audio buffer userdata Pointer the user data which is passed to the call- back function


The SDL_AudioSpec structure is used to describe the format of some audio data. This structure is used by SDL_OpenAudio and SDL_LoadWAV. While all fields are used by SDL_OpenAudio only freq, format, samples and channels are used by SDL_LoadWAV. We will detail these common mem- bers here. freq The number of samples sent to the sound device every second. Common values are 11025, 22050 and 44100. The higher the better. format Specifies the size and type of each sample element AUDIO_U8 AUDIO_S8 AUDIO_U16 or AUDIO_U16LSB AUDIO_S16 or AUDIO_S16LSB AUDIO_U16MSB AUDIO_S16MSB AUDIO_U16SYS AUDIO_S16SYS channels The number of seperate sound channels. 1 is mono (single channel), 2 is stereo (dual channel). samples When used with SDL_OpenAudio this refers to the size of the audio buffer in samples. A sample a chunk of audio data of the size specified in format mulitplied by the number of channels. When the SDL_AudioSpec is used with SDL_LoadWAV samples is set to 4096.


SDL_OpenAudio, SDL_LoadWAV SDL Tue 11 Sep 2001, 22:58 SDL_AudioSpec(3)

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