cannam@86: /********************************************************************
cannam@86:  *                                                                  *
cannam@86:  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
cannam@86:  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
cannam@86:  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
cannam@86:  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
cannam@86:  *                                                                  *
cannam@86:  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2007             *
cannam@86:  * by the Xiph.Org Foundation http://www.xiph.org/                  *
cannam@86:  *                                                                  *
cannam@86:  ********************************************************************
cannam@86: 
cannam@86:  function: simple example encoder
cannam@86:  last mod: $Id: encoder_example.c 16946 2010-03-03 16:12:40Z xiphmont $
cannam@86: 
cannam@86:  ********************************************************************/
cannam@86: 
cannam@86: /* takes a stereo 16bit 44.1kHz WAV file from stdin and encodes it into
cannam@86:    a Vorbis bitstream */
cannam@86: 
cannam@86: /* Note that this is POSIX, not ANSI, code */
cannam@86: 
cannam@86: #include <stdio.h>
cannam@86: #include <stdlib.h>
cannam@86: #include <string.h>
cannam@86: #include <time.h>
cannam@86: #include <math.h>
cannam@86: #include <vorbis/vorbisenc.h>
cannam@86: 
cannam@86: #ifdef _WIN32 /* We need the following two to set stdin/stdout to binary */
cannam@86: #include <io.h>
cannam@86: #include <fcntl.h>
cannam@86: #endif
cannam@86: 
cannam@86: #if defined(__MACOS__) && defined(__MWERKS__)
cannam@86: #include <console.h>      /* CodeWarrior's Mac "command-line" support */
cannam@86: #endif
cannam@86: 
cannam@86: #define READ 1024
cannam@86: signed char readbuffer[READ*4+44]; /* out of the data segment, not the stack */
cannam@86: 
cannam@86: int main(){
cannam@86:   ogg_stream_state os; /* take physical pages, weld into a logical
cannam@86:                           stream of packets */
cannam@86:   ogg_page         og; /* one Ogg bitstream page.  Vorbis packets are inside */
cannam@86:   ogg_packet       op; /* one raw packet of data for decode */
cannam@86: 
cannam@86:   vorbis_info      vi; /* struct that stores all the static vorbis bitstream
cannam@86:                           settings */
cannam@86:   vorbis_comment   vc; /* struct that stores all the user comments */
cannam@86: 
cannam@86:   vorbis_dsp_state vd; /* central working state for the packet->PCM decoder */
cannam@86:   vorbis_block     vb; /* local working space for packet->PCM decode */
cannam@86: 
cannam@86:   int eos=0,ret;
cannam@86:   int i, founddata;
cannam@86: 
cannam@86: #if defined(macintosh) && defined(__MWERKS__)
cannam@86:   int argc = 0;
cannam@86:   char **argv = NULL;
cannam@86:   argc = ccommand(&argv); /* get a "command line" from the Mac user */
cannam@86:                           /* this also lets the user set stdin and stdout */
cannam@86: #endif
cannam@86: 
cannam@86:   /* we cheat on the WAV header; we just bypass 44 bytes (simplest WAV
cannam@86:      header is 44 bytes) and assume that the data is 44.1khz, stereo, 16 bit
cannam@86:      little endian pcm samples. This is just an example, after all. */
cannam@86: 
cannam@86: #ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */
cannam@86:   /* if we were reading/writing a file, it would also need to in
cannam@86:      binary mode, eg, fopen("file.wav","wb"); */
cannam@86:   /* Beware the evil ifdef. We avoid these where we can, but this one we
cannam@86:      cannot. Don't add any more, you'll probably go to hell if you do. */
cannam@86:   _setmode( _fileno( stdin ), _O_BINARY );
cannam@86:   _setmode( _fileno( stdout ), _O_BINARY );
cannam@86: #endif
cannam@86: 
cannam@86: 
cannam@86:   /* we cheat on the WAV header; we just bypass the header and never
cannam@86:      verify that it matches 16bit/stereo/44.1kHz.  This is just an
cannam@86:      example, after all. */
cannam@86: 
cannam@86:   readbuffer[0] = '\0';
cannam@86:   for (i=0, founddata=0; i<30 && ! feof(stdin) && ! ferror(stdin); i++)
cannam@86:   {
cannam@86:     fread(readbuffer,1,2,stdin);
cannam@86: 
cannam@86:     if ( ! strncmp((char*)readbuffer, "da", 2) ){
cannam@86:       founddata = 1;
cannam@86:       fread(readbuffer,1,6,stdin);
cannam@86:       break;
cannam@86:     }
cannam@86:   }
cannam@86: 
cannam@86:   /********** Encode setup ************/
cannam@86: 
cannam@86:   vorbis_info_init(&vi);
cannam@86: 
cannam@86:   /* choose an encoding mode.  A few possibilities commented out, one
cannam@86:      actually used: */
cannam@86: 
cannam@86:   /*********************************************************************
cannam@86:    Encoding using a VBR quality mode.  The usable range is -.1
cannam@86:    (lowest quality, smallest file) to 1. (highest quality, largest file).
cannam@86:    Example quality mode .4: 44kHz stereo coupled, roughly 128kbps VBR
cannam@86: 
cannam@86:    ret = vorbis_encode_init_vbr(&vi,2,44100,.4);
cannam@86: 
cannam@86:    ---------------------------------------------------------------------
cannam@86: 
cannam@86:    Encoding using an average bitrate mode (ABR).
cannam@86:    example: 44kHz stereo coupled, average 128kbps VBR
cannam@86: 
cannam@86:    ret = vorbis_encode_init(&vi,2,44100,-1,128000,-1);
cannam@86: 
cannam@86:    ---------------------------------------------------------------------
cannam@86: 
cannam@86:    Encode using a quality mode, but select that quality mode by asking for
cannam@86:    an approximate bitrate.  This is not ABR, it is true VBR, but selected
cannam@86:    using the bitrate interface, and then turning bitrate management off:
cannam@86: 
cannam@86:    ret = ( vorbis_encode_setup_managed(&vi,2,44100,-1,128000,-1) ||
cannam@86:            vorbis_encode_ctl(&vi,OV_ECTL_RATEMANAGE2_SET,NULL) ||
cannam@86:            vorbis_encode_setup_init(&vi));
cannam@86: 
cannam@86:    *********************************************************************/
cannam@86: 
cannam@86:   ret=vorbis_encode_init_vbr(&vi,2,44100,0.1);
cannam@86: 
cannam@86:   /* do not continue if setup failed; this can happen if we ask for a
cannam@86:      mode that libVorbis does not support (eg, too low a bitrate, etc,
cannam@86:      will return 'OV_EIMPL') */
cannam@86: 
cannam@86:   if(ret)exit(1);
cannam@86: 
cannam@86:   /* add a comment */
cannam@86:   vorbis_comment_init(&vc);
cannam@86:   vorbis_comment_add_tag(&vc,"ENCODER","encoder_example.c");
cannam@86: 
cannam@86:   /* set up the analysis state and auxiliary encoding storage */
cannam@86:   vorbis_analysis_init(&vd,&vi);
cannam@86:   vorbis_block_init(&vd,&vb);
cannam@86: 
cannam@86:   /* set up our packet->stream encoder */
cannam@86:   /* pick a random serial number; that way we can more likely build
cannam@86:      chained streams just by concatenation */
cannam@86:   srand(time(NULL));
cannam@86:   ogg_stream_init(&os,rand());
cannam@86: 
cannam@86:   /* Vorbis streams begin with three headers; the initial header (with
cannam@86:      most of the codec setup parameters) which is mandated by the Ogg
cannam@86:      bitstream spec.  The second header holds any comment fields.  The
cannam@86:      third header holds the bitstream codebook.  We merely need to
cannam@86:      make the headers, then pass them to libvorbis one at a time;
cannam@86:      libvorbis handles the additional Ogg bitstream constraints */
cannam@86: 
cannam@86:   {
cannam@86:     ogg_packet header;
cannam@86:     ogg_packet header_comm;
cannam@86:     ogg_packet header_code;
cannam@86: 
cannam@86:     vorbis_analysis_headerout(&vd,&vc,&header,&header_comm,&header_code);
cannam@86:     ogg_stream_packetin(&os,&header); /* automatically placed in its own
cannam@86:                                          page */
cannam@86:     ogg_stream_packetin(&os,&header_comm);
cannam@86:     ogg_stream_packetin(&os,&header_code);
cannam@86: 
cannam@86:     /* This ensures the actual
cannam@86:      * audio data will start on a new page, as per spec
cannam@86:      */
cannam@86:     while(!eos){
cannam@86:       int result=ogg_stream_flush(&os,&og);
cannam@86:       if(result==0)break;
cannam@86:       fwrite(og.header,1,og.header_len,stdout);
cannam@86:       fwrite(og.body,1,og.body_len,stdout);
cannam@86:     }
cannam@86: 
cannam@86:   }
cannam@86: 
cannam@86:   while(!eos){
cannam@86:     long i;
cannam@86:     long bytes=fread(readbuffer,1,READ*4,stdin); /* stereo hardwired here */
cannam@86: 
cannam@86:     if(bytes==0){
cannam@86:       /* end of file.  this can be done implicitly in the mainline,
cannam@86:          but it's easier to see here in non-clever fashion.
cannam@86:          Tell the library we're at end of stream so that it can handle
cannam@86:          the last frame and mark end of stream in the output properly */
cannam@86:       vorbis_analysis_wrote(&vd,0);
cannam@86: 
cannam@86:     }else{
cannam@86:       /* data to encode */
cannam@86: 
cannam@86:       /* expose the buffer to submit data */
cannam@86:       float **buffer=vorbis_analysis_buffer(&vd,READ);
cannam@86: 
cannam@86:       /* uninterleave samples */
cannam@86:       for(i=0;i<bytes/4;i++){
cannam@86:         buffer[0][i]=((readbuffer[i*4+1]<<8)|
cannam@86:                       (0x00ff&(int)readbuffer[i*4]))/32768.f;
cannam@86:         buffer[1][i]=((readbuffer[i*4+3]<<8)|
cannam@86:                       (0x00ff&(int)readbuffer[i*4+2]))/32768.f;
cannam@86:       }
cannam@86: 
cannam@86:       /* tell the library how much we actually submitted */
cannam@86:       vorbis_analysis_wrote(&vd,i);
cannam@86:     }
cannam@86: 
cannam@86:     /* vorbis does some data preanalysis, then divvies up blocks for
cannam@86:        more involved (potentially parallel) processing.  Get a single
cannam@86:        block for encoding now */
cannam@86:     while(vorbis_analysis_blockout(&vd,&vb)==1){
cannam@86: 
cannam@86:       /* analysis, assume we want to use bitrate management */
cannam@86:       vorbis_analysis(&vb,NULL);
cannam@86:       vorbis_bitrate_addblock(&vb);
cannam@86: 
cannam@86:       while(vorbis_bitrate_flushpacket(&vd,&op)){
cannam@86: 
cannam@86:         /* weld the packet into the bitstream */
cannam@86:         ogg_stream_packetin(&os,&op);
cannam@86: 
cannam@86:         /* write out pages (if any) */
cannam@86:         while(!eos){
cannam@86:           int result=ogg_stream_pageout(&os,&og);
cannam@86:           if(result==0)break;
cannam@86:           fwrite(og.header,1,og.header_len,stdout);
cannam@86:           fwrite(og.body,1,og.body_len,stdout);
cannam@86: 
cannam@86:           /* this could be set above, but for illustrative purposes, I do
cannam@86:              it here (to show that vorbis does know where the stream ends) */
cannam@86: 
cannam@86:           if(ogg_page_eos(&og))eos=1;
cannam@86:         }
cannam@86:       }
cannam@86:     }
cannam@86:   }
cannam@86: 
cannam@86:   /* clean up and exit.  vorbis_info_clear() must be called last */
cannam@86: 
cannam@86:   ogg_stream_clear(&os);
cannam@86:   vorbis_block_clear(&vb);
cannam@86:   vorbis_dsp_clear(&vd);
cannam@86:   vorbis_comment_clear(&vc);
cannam@86:   vorbis_info_clear(&vi);
cannam@86: 
cannam@86:   /* ogg_page and ogg_packet structs always point to storage in
cannam@86:      libvorbis.  They're never freed or manipulated directly */
cannam@86: 
cannam@86:   fprintf(stderr,"Done.\n");
cannam@86:   return(0);
cannam@86: }