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 1.27 2001/09/19 01:17:00 cwolf 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 */
27 #include <vorbis/vorbisenc.h>
29 #ifdef _WIN32 /* We need the following two to set stdin/stdout to binary */
34 #if defined(macintosh) && defined(__MWERKS__)
35 #include <console.h> /* CodeWarrior's Mac "command-line" support */
39 signed char readbuffer[READ*4+44]; /* out of the data segment, not the stack */
42 ogg_stream_state os; /* take physical pages, weld into a logical
44 ogg_page og; /* one Ogg bitstream page. Vorbis packets are inside */
45 ogg_packet op; /* one raw packet of data for decode */
47 vorbis_info vi; /* struct that stores all the static vorbis bitstream
49 vorbis_comment vc; /* struct that stores all the user comments */
51 vorbis_dsp_state vd; /* central working state for the packet->PCM decoder */
52 vorbis_block vb; /* local working space for packet->PCM decode */
57 #if defined(macintosh) && defined(__MWERKS__)
60 argc = ccommand(&argv); /* get a "command line" from the Mac user */
61 /* this also lets the user set stdin and stdout */
64 /* we cheat on the WAV header; we just bypass 44 bytes and never
65 verify that it matches 16bit/stereo/44.1kHz. This is just an
66 example, after all. */
68 #ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */
69 /* Beware the evil ifdef. We avoid these where we can, but this one we
70 cannot. Don't add any more, you'll probably go to hell if you do. */
71 _setmode( _fileno( stdin ), _O_BINARY );
72 _setmode( _fileno( stdout ), _O_BINARY );
75 /* we cheat on the WAV header; we just bypass the header and never
76 verify that it matches 16bit/stereo/44.1kHz. This is just an
77 example, after all. */
80 for (i=0, founddata=0; i<30 && ! feof(stdin) && ! ferror(stdin); i++)
82 fread(readbuffer,1,2,stdin);
84 if ( ! strncmp(readbuffer, "da", 2) )
87 fread(readbuffer,1,6,stdin);
91 /********** Encode setup ************/
93 /* choose an encoding mode */
94 /* (mode 0: 44kHz stereo uncoupled, roughly 128kbps VBR) */
95 vorbis_info_init(&vi);
96 vorbis_encode_init(&vi,2,44100, -1, 128000, -1);
99 vorbis_comment_init(&vc);
100 vorbis_comment_add(&vc,"Track encoded by encoder_example.c");
102 /* set up the analysis state and auxiliary encoding storage */
103 vorbis_analysis_init(&vd,&vi);
104 vorbis_block_init(&vd,&vb);
106 /* set up our packet->stream encoder */
107 /* pick a random serial number; that way we can more likely build
108 chained streams just by concatenation */
110 ogg_stream_init(&os,rand());
112 /* Vorbis streams begin with three headers; the initial header (with
113 most of the codec setup parameters) which is mandated by the Ogg
114 bitstream spec. The second header holds any comment fields. The
115 third header holds the bitstream codebook. We merely need to
116 make the headers, then pass them to libvorbis one at a time;
117 libvorbis handles the additional Ogg bitstream constraints */
121 ogg_packet header_comm;
122 ogg_packet header_code;
124 vorbis_analysis_headerout(&vd,&vc,&header,&header_comm,&header_code);
125 ogg_stream_packetin(&os,&header); /* automatically placed in its own
127 ogg_stream_packetin(&os,&header_comm);
128 ogg_stream_packetin(&os,&header_code);
130 /* We don't have to write out here, but doing so makes streaming
131 * much easier, so we do, flushing ALL pages. This ensures the actual
132 * audio data will start on a new page
135 int result=ogg_stream_flush(&os,&og);
137 fwrite(og.header,1,og.header_len,stdout);
138 fwrite(og.body,1,og.body_len,stdout);
145 long bytes=fread(readbuffer,1,READ*4,stdin); /* stereo hardwired here */
148 /* end of file. this can be done implicitly in the mainline,
149 but it's easier to see here in non-clever fashion.
150 Tell the library we're at end of stream so that it can handle
151 the last frame and mark end of stream in the output properly */
152 vorbis_analysis_wrote(&vd,0);
157 /* expose the buffer to submit data */
158 float **buffer=vorbis_analysis_buffer(&vd,READ);
160 /* uninterleave samples */
161 for(i=0;i<bytes/4;i++){
162 buffer[0][i]=((readbuffer[i*4+1]<<8)|
163 (0x00ff&(int)readbuffer[i*4]))/32768.f;
164 buffer[1][i]=((readbuffer[i*4+3]<<8)|
165 (0x00ff&(int)readbuffer[i*4+2]))/32768.f;
168 /* tell the library how much we actually submitted */
169 vorbis_analysis_wrote(&vd,i);
172 /* vorbis does some data preanalysis, then divvies up blocks for
173 more involved (potentially parallel) processing. Get a single
174 block for encoding now */
175 while(vorbis_analysis_blockout(&vd,&vb)==1){
178 vorbis_analysis(&vb,&op);
180 /* weld the packet into the bitstream */
181 ogg_stream_packetin(&os,&op);
183 /* write out pages (if any) */
185 int result=ogg_stream_pageout(&os,&og);
187 fwrite(og.header,1,og.header_len,stdout);
188 fwrite(og.body,1,og.body_len,stdout);
190 /* this could be set above, but for illustrative purposes, I do
191 it here (to show that vorbis does know where the stream ends) */
193 if(ogg_page_eos(&og))eos=1;
199 /* clean up and exit. vorbis_info_clear() must be called last */
201 ogg_stream_clear(&os);
202 vorbis_block_clear(&vb);
203 vorbis_dsp_clear(&vd);
204 vorbis_comment_clear(&vc);
205 vorbis_info_clear(&vi);
207 /* ogg_page and ogg_packet structs always point to storage in
208 libvorbis. They're never freed or manipulated directly */
210 fprintf(stderr,"Done.\n");