release/src/router/libvorbis/examples/vorbisfile_example.c

   1 /********************************************************************
   2  *                                                                  *
   3  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
   4  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
   5  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
   6  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
   7  *                                                                  *
   8  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2007             *
   9  * by the Xiph.Org Foundation http://www.xiph.org/                  *
  10  *                                                                  *
  11  ********************************************************************
  12
  13  function: simple example decoder using vorbisfile
  14  last mod: $Id: vorbisfile_example.c 16037 2009-05-26 21:10:58Z xiphmont $
  15
  16  ********************************************************************/
  17
  18 /* Takes a vorbis bitstream from stdin and writes raw stereo PCM to
  19    stdout using vorbisfile. Using vorbisfile is much simpler than
  20    dealing with libvorbis. */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <math.h>
  25 #include <vorbis/codec.h>
  26 #include <vorbis/vorbisfile.h>
  27
  28 #ifdef _WIN32 /* We need the following two to set stdin/stdout to binary */
  29 #include <io.h>
  30 #include <fcntl.h>
  31 #endif
  32
  33 char pcmout[4096]; /* take 4k out of the data segment, not the stack */
  34
  35 int main(){
  36   OggVorbis_File vf;
  37   int eof=0;
  38   int current_section;
  39
  40 #ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */
  41   /* Beware the evil ifdef. We avoid these where we can, but this one we
  42      cannot. Don't add any more, you'll probably go to hell if you do. */
  43   _setmode( _fileno( stdin ), _O_BINARY );
  44   _setmode( _fileno( stdout ), _O_BINARY );
  45 #endif
  46
  47   if(ov_open_callbacks(stdin, &vf, NULL, 0, OV_CALLBACKS_NOCLOSE) < 0) {
  48       fprintf(stderr,"Input does not appear to be an Ogg bitstream.\n");
  49       exit(1);
  50   }
  51
  52   /* Throw the comments plus a few lines about the bitstream we're
  53      decoding */
  54   {
  55     char **ptr=ov_comment(&vf,-1)->user_comments;
  56     vorbis_info *vi=ov_info(&vf,-1);
  57     while(*ptr){
  58       fprintf(stderr,"%s\n",*ptr);
  59       ++ptr;
  60     }
  61     fprintf(stderr,"\nBitstream is %d channel, %ldHz\n",vi->channels,vi->rate);
  62     fprintf(stderr,"\nDecoded length: %ld samples\n",
  63             (long)ov_pcm_total(&vf,-1));
  64     fprintf(stderr,"Encoded by: %s\n\n",ov_comment(&vf,-1)->vendor);
  65   }
  66
  67   while(!eof){
  68     long ret=ov_read(&vf,pcmout,sizeof(pcmout),0,2,1,&current_section);
  69     if (ret == 0) {
  70       /* EOF */
  71       eof=1;
  72     } else if (ret < 0) {
  73       /* error in the stream.  Not a problem, just reporting it in
  74          case we (the app) cares.  In this case, we don't. */
  75     } else {
  76       /* we don't bother dealing with sample rate changes, etc, but
  77          you'll have to*/
  78       fwrite(pcmout,1,ret,stdout);
  79     }
  80   }
  81
  82   /* cleanup */
  83   ov_clear(&vf);
  84
  85   fprintf(stderr,"Done.\n");
  86   return(0);
  87 }