SDL_AudioSpec(3) SDL API Reference SDL_AudioSpec(3)NAME
SDL_AudioSpec- Audio Specification Structure
STRUCTURE DEFINITION
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;
STRUCTURE DATA
freq Audio frequency in samples per second
format Audio data format
channels Number of channels: 1 mono, 2 stereo
silence Audio buffer silence value (calcu-
lated)
samples Audio buffer size in samples
size Audio buffer size in bytes (calcu-
lated)
callback(..) Callback function for filling the
audio buffer
userdata Pointer the user data which is passed
to the callback function
DESCRIPTION
The SDL_AudioSpec structure is used to describe the format
of some audio data. This structure is used by SDL_OpenAu-
dio and SDL_LoadWAV. While all fields are used by SDL_Ope-
nAudio only freq, format, samples and channels are used by
SDL_LoadWAV. We will detail these common members here.
freq The number of samples sent to the
sound device every second. Common val-
ues 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.
SEE ALSO
SDL_OpenAudio, SDL_LoadWAV
SDL Tue 11 Sep 2001, 22:58 SDL_AudioSpec(3)