sdl_loadwav(3) [opensolaris man page]

SDL_LoadWAV(3)							 SDL API Reference						    SDL_LoadWAV(3)

NAME

       SDL_LoadWAV - Load a WAVE file

SYNOPSIS

       #include "SDL.h"

       SDL_AudioSpec *SDL_LoadWAV(const char *file, SDL_AudioSpec *spec, Uint8 **audio_buf, Uint32 *audio_len);

DESCRIPTION

       SDL_LoadWAV This function loads a WAVE file into memory.

       If  this function succeeds, it returns the given SDL_AudioSpec, filled with the audio data format of the wave data, and sets audio_buf to a
       malloc'd buffer containing the audio data, and sets audio_len to the length of that audio buffer, in bytes. You need to free the audio buf-
       fer with SDL_FreeWAV when you are done with it.

       This  function  returns	NULL and sets the SDL error message if the wave file cannot be opened, uses an unknown data format, or is corrupt.
       Currently raw, MS-ADPCM and IMA-ADPCM WAVE files are supported.

EXAMPLE

       SDL_AudioSpec wav_spec;
       Uint32 wav_length;
       Uint8 *wav_buffer;

       /* Load the WAV */
       if( SDL_LoadWAV("test.wav", &wav_spec, &wav_buffer, &wav_length) == NULL ){
	 fprintf(stderr, "Could not open test.wav: %s
       ", SDL_GetError());
	 exit(-1);
       }
       .
       .
       .
       /* Do stuff with the WAV */
       .
       .
       /* Free It */
       SDL_FreeWAV(wav_buffer);

SEE ALSO

       SDL_AudioSpec, SDL_OpenAudio, SDL_FreeWAV

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

SDL_ConvertAudio(3)						 SDL API Reference					       SDL_ConvertAudio(3)

NAME

       SDL_ConvertAudio- Convert audio data to a desired audio format.

SYNOPSIS

       #include "SDL.h"

       int SDL_ConvertAudio(SDL_AudioCVT *cvt);

DESCRIPTION

       SDL_ConvertAudio takes one parameter, cvt, which was previously initilized. Initilizing a SDL_AudioCVT is a two step process. First of all,
       the structure must be passed to SDL_BuildAudioCVT along with source and destination format parameters. Secondly, the cvt->buf and  cvt->len
       fields  must  be setup. cvt->buf should point to the audio data and cvt->len should be set to the length of the audio data in bytes. Remem-
       ber, the length of the buffer pointed to by buf show be len*len_mult bytes in length.

       Once the SDL_AudioCVTstructure is initilized then we can pass it to SDL_ConvertAudio, which will convert  the  audio  data  pointer  to	by
       cvt->buf. If SDL_ConvertAudio returned 0 then the conversion was completed successfully, otherwise -1 is returned.

       If  the	conversion  completed  successfully then the converted audio data can be read from cvt->buf. The amount of valid, converted, audio
       data in the buffer is equal to cvt->len*cvt->len_ratio.

EXAMPLES

       /* Converting some WAV data to hardware format */
       void my_audio_callback(void *userdata, Uint8 *stream, int len);

       SDL_AudioSpec *desired, *obtained;
       SDL_AudioSpec wav_spec;
       SDL_AudioCVT  wav_cvt;
       Uint32 wav_len;
       Uint8 *wav_buf;
       int ret;

       /* Allocated audio specs */
       desired=(SDL_AudioSpec *)malloc(sizeof(SDL_AudioSpec));
       obtained=(SDL_AudioSpec *)malloc(sizeof(SDL_AudioSpec));

       /* Set desired format */
       desired->freq=22050;
       desired->format=AUDIO_S16LSB;
       desired->samples=8192;
       desired->callback=my_audio_callback;
       desired->userdata=NULL;

       /* Open the audio device */
       if ( SDL_OpenAudio(desired, obtained) < 0 ){
	 fprintf(stderr, "Couldn't open audio: %s
       ", SDL_GetError());
	 exit(-1);
       }

       free(desired);

       /* Load the test.wav */
       if( SDL_LoadWAV("test.wav", &wav_spec, &wav_buf, &wav_len) == NULL ){
	 fprintf(stderr, "Could not open test.wav: %s
       ", SDL_GetError());
	 SDL_CloseAudio();
	 free(obtained);
	 exit(-1);
       }

       /* Build AudioCVT */
       ret = SDL_BuildAudioCVT(&wav_cvt,
			       wav_spec.format, wav_spec.channels, wav_spec.freq,
			       obtained->format, obtained->channels, obtained->freq);

       /* Check that the convert was built */
       if(ret==-1){
	 fprintf(stderr, "Couldn't build converter!
       ");
	 SDL_CloseAudio();
	 free(obtained);
	 SDL_FreeWAV(wav_buf);
       }

       /* Setup for conversion */
       wav_cvt.buf=(Uint8 *)malloc(wav_len*wav_cvt.len_mult);
       wav_cvt.len=wav_len;
       memcpy(wav_cvt.buf, wav_buf, wav_len);

       /* We can delete to original WAV data now */
       SDL_FreeWAV(wav_buf);

       /* And now we're ready to convert */
       SDL_ConvertAudio(&wav_cvt);

       /* do whatever */
       .
       .
       .
       .

SEE ALSO

       SDL_BuildAudioCVT, SDL_AudioCVT

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