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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 (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

DESCRIPTION
       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.

SEE ALSO
       SDL_OpenAudio, SDL_LoadWAV

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