1 /********************************************************************
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. *
8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 *
9 * by the XIPHOPHORUS Company http://www.xiph.org/ *
11 ********************************************************************
13 function: simple example encoder
14 last mod: $Id: encoder_example.c,v 1.40 2002/03/29 07:10:38 xiphmont Exp $
16 ********************************************************************/
18 /* takes a stereo 16bit 44.1kHz WAV file from stdin and encodes it into
21 /* Note that this is POSIX, not ANSI, code */
28 #include <vorbis/vorbisenc.h>
30 #ifdef _WIN32 /* We need the following two to set stdin/stdout to binary */
35 #if defined(macintosh) && defined(__MWERKS__)
36 #include <console.h> /* CodeWarrior's Mac "command-line" support */
40 signed char readbuffer[READ*4+44]; /* out of the data segment, not the stack */
43 ogg_stream_state os; /* take physical pages, weld into a logical
45 ogg_page og; /* one Ogg bitstream page. Vorbis packets are inside */
46 ogg_packet op; /* one raw packet of data for decode */
48 vorbis_info vi; /* struct that stores all the static vorbis bitstream
50 vorbis_comment vc; /* struct that stores all the user comments */
52 vorbis_dsp_state vd; /* central working state for the packet->PCM decoder */
53 vorbis_block vb; /* local working space for packet->PCM decode */
58 #if defined(macintosh) && defined(__MWERKS__)
61 argc = ccommand(&argv); /* get a "command line" from the Mac user */
62 /* this also lets the user set stdin and stdout */
65 /* we cheat on the WAV header; we just bypass 44 bytes and never
66 verify that it matches 16bit/stereo/44.1kHz. This is just an
67 example, after all. */
69 #ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */
70 /* Beware the evil ifdef. We avoid these where we can, but this one we
71 cannot. Don't add any more, you'll probably go to hell if you do. */
72 _setmode( _fileno( stdin ), _O_BINARY );
73 _setmode( _fileno( stdout ), _O_BINARY );
77 /* we cheat on the WAV header; we just bypass the header and never
78 verify that it matches 16bit/stereo/44.1kHz. This is just an
79 example, after all. */
82 for (i=0, founddata=0; i<30 && ! feof(stdin) && ! ferror(stdin); i++)
84 fread(readbuffer,1,2,stdin);
86 if ( ! strncmp(readbuffer, "da", 2) )
89 fread(readbuffer,1,6,stdin);
94 /********** Encode setup ************/
96 /* choose an encoding mode */
97 /* (quality mode .4: 44kHz stereo coupled, roughly 128kbps VBR) */
98 vorbis_info_init(&vi);
100 vorbis_encode_init_vbr(&vi,2,44100,.4);
103 vorbis_comment_init(&vc);
104 vorbis_comment_add_tag(&vc,"ENCODER","encoder_example.c");
106 /* set up the analysis state and auxiliary encoding storage */
107 vorbis_analysis_init(&vd,&vi);
108 vorbis_block_init(&vd,&vb);
110 /* set up our packet->stream encoder */
111 /* pick a random serial number; that way we can more likely build
112 chained streams just by concatenation */
114 ogg_stream_init(&os,rand());
116 /* Vorbis streams begin with three headers; the initial header (with
117 most of the codec setup parameters) which is mandated by the Ogg
118 bitstream spec. The second header holds any comment fields. The
119 third header holds the bitstream codebook. We merely need to
120 make the headers, then pass them to libvorbis one at a time;
121 libvorbis handles the additional Ogg bitstream constraints */
125 ogg_packet header_comm;
126 ogg_packet header_code;
128 vorbis_analysis_headerout(&vd,&vc,&header,&header_comm,&header_code);
129 ogg_stream_packetin(&os,&header); /* automatically placed in its own
131 ogg_stream_packetin(&os,&header_comm);
132 ogg_stream_packetin(&os,&header_code);
134 /* We don't have to write out here, but doing so makes streaming
135 * much easier, so we do, flushing ALL pages. This ensures the actual
136 * audio data will start on a new page
139 int result=ogg_stream_flush(&os,&og);
141 fwrite(og.header,1,og.header_len,stdout);
142 fwrite(og.body,1,og.body_len,stdout);
149 long bytes=fread(readbuffer,1,READ*4,stdin); /* stereo hardwired here */
152 /* end of file. this can be done implicitly in the mainline,
153 but it's easier to see here in non-clever fashion.
154 Tell the library we're at end of stream so that it can handle
155 the last frame and mark end of stream in the output properly */
156 vorbis_analysis_wrote(&vd,0);
161 /* expose the buffer to submit data */
162 float **buffer=vorbis_analysis_buffer(&vd,READ);
164 /* uninterleave samples */
165 for(i=0;i<bytes/4;i++){
166 buffer[0][i]=((readbuffer[i*4+1]<<8)|
167 (0x00ff&(int)readbuffer[i*4]))/32768.f;
168 buffer[1][i]=((readbuffer[i*4+3]<<8)|
169 (0x00ff&(int)readbuffer[i*4+2]))/32768.f;
172 /* tell the library how much we actually submitted */
173 vorbis_analysis_wrote(&vd,i);
176 /* vorbis does some data preanalysis, then divvies up blocks for
177 more involved (potentially parallel) processing. Get a single
178 block for encoding now */
179 while(vorbis_analysis_blockout(&vd,&vb)==1){
181 /* analysis, assume we want to use bitrate management */
182 vorbis_analysis(&vb,NULL);
183 vorbis_bitrate_addblock(&vb);
185 while(vorbis_bitrate_flushpacket(&vd,&op)){
187 /* weld the packet into the bitstream */
188 ogg_stream_packetin(&os,&op);
190 /* write out pages (if any) */
192 int result=ogg_stream_pageout(&os,&og);
194 fwrite(og.header,1,og.header_len,stdout);
195 fwrite(og.body,1,og.body_len,stdout);
197 /* this could be set above, but for illustrative purposes, I do
198 it here (to show that vorbis does know where the stream ends) */
200 if(ogg_page_eos(&og))eos=1;
206 /* clean up and exit. vorbis_info_clear() must be called last */
208 ogg_stream_clear(&os);
209 vorbis_block_clear(&vb);
210 vorbis_dsp_clear(&vd);
211 vorbis_comment_clear(&vc);
212 vorbis_info_clear(&vi);
214 /* ogg_page and ogg_packet structs always point to storage in
215 libvorbis. They're never freed or manipulated directly */
217 fprintf(stderr,"Done.\n");