GNU/Linux |
CentOS 5.3 |
|
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 callback 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 members 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_AudioSpec(3) |