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/********************************************************************
* *
* THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
* USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
* GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
* IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
* *
* THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2007 *
* by the Xiph.Org Foundation http://www.xiph.org/ *
* *
********************************************************************
function: simple example decoder using vorbisfile
********************************************************************/
/* Takes a vorbis bitstream from stdin and writes raw stereo PCM to
stdout using vorbisfile. Using vorbisfile is much simpler than
dealing with libvorbis. */
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <vorbis/codec.h>
#include <vorbis/vorbisfile.h>
#ifdef _WIN32 /* We need the following two to set stdin/stdout to binary */
#include <io.h>
#include <fcntl.h>
#endif
char pcmout[4096]; /* take 4k out of the data segment, not the stack */
int main(){
OggVorbis_File vf;
int eof=0;
int current_section;
#ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */
/* Beware the evil ifdef. We avoid these where we can, but this one we
cannot. Don't add any more, you'll probably go to hell if you do. */
_setmode( _fileno( stdin ), _O_BINARY );
_setmode( _fileno( stdout ), _O_BINARY );
#endif
if(ov_open_callbacks(stdin, &vf, NULL, 0, OV_CALLBACKS_NOCLOSE) < 0) {
fprintf(stderr,"Input does not appear to be an Ogg bitstream.\n");
exit(1);
}
/* Throw the comments plus a few lines about the bitstream we're
decoding */
{
char **ptr=ov_comment(&vf,-1)->user_comments;
vorbis_info *vi=ov_info(&vf,-1);
while(*ptr){
fprintf(stderr,"%s\n",*ptr);
++ptr;
}
fprintf(stderr,"\nBitstream is %d channel, %ldHz\n",vi->channels,vi->rate);
fprintf(stderr,"\nDecoded length: %ld samples\n",
(long)ov_pcm_total(&vf,-1));
fprintf(stderr,"Encoded by: %s\n\n",ov_comment(&vf,-1)->vendor);
}
while(!eof){
long ret=ov_read(&vf,pcmout,sizeof(pcmout),0,2,1,¤t_section);
if (ret == 0) {
/* EOF */
eof=1;
} else if (ret < 0) {
if(ret==OV_EBADLINK){
fprintf(stderr,"Corrupt bitstream section! Exiting.\n");
exit(1);
}
/* some other error in the stream. Not a problem, just reporting it in
case we (the app) cares. In this case, we don't. */
} else {
/* we don't bother dealing with sample rate changes, etc, but
you'll have to*/
fwrite(pcmout,1,ret,stdout);
}
}
/* cleanup */
ov_clear(&vf);
fprintf(stderr,"Done.\n");
return(0);
}
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