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 1.30 2001/12/19 01:08:13 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 );
76 /* we cheat on the WAV header; we just bypass the header and never
77 verify that it matches 16bit/stereo/44.1kHz. This is just an
78 example, after all. */
81 for (i=0, founddata=0; i<30 && ! feof(stdin) && ! ferror(stdin); i++)
83 fread(readbuffer,1,2,stdin);
85 if ( ! strncmp(readbuffer, "da", 2) )
88 fread(readbuffer,1,6,stdin);
93 /********** Encode setup ************/
95 /* choose an encoding mode */
96 /* (mode 0: 44kHz stereo uncoupled, roughly 128kbps VBR) */
97 vorbis_info_init(&vi);
99 vorbis_encode_init_vbr(&vi,2,44100,.4);
102 vorbis_comment_init(&vc);
103 vorbis_comment_add(&vc,"ENCODER=encoder_example.c");
105 /* set up the analysis state and auxiliary encoding storage */
106 vorbis_analysis_init(&vd,&vi);
107 vorbis_block_init(&vd,&vb);
109 /* set up our packet->stream encoder */
110 /* pick a random serial number; that way we can more likely build
111 chained streams just by concatenation */
113 ogg_stream_init(&os,rand());
115 /* Vorbis streams begin with three headers; the initial header (with
116 most of the codec setup parameters) which is mandated by the Ogg
117 bitstream spec. The second header holds any comment fields. The
118 third header holds the bitstream codebook. We merely need to
119 make the headers, then pass them to libvorbis one at a time;
120 libvorbis handles the additional Ogg bitstream constraints */
124 ogg_packet header_comm;
125 ogg_packet header_code;
127 vorbis_analysis_headerout(&vd,&vc,&header,&header_comm,&header_code);
128 ogg_stream_packetin(&os,&header); /* automatically placed in its own
130 ogg_stream_packetin(&os,&header_comm);
131 ogg_stream_packetin(&os,&header_code);
133 /* We don't have to write out here, but doing so makes streaming
134 * much easier, so we do, flushing ALL pages. This ensures the actual
135 * audio data will start on a new page
138 int result=ogg_stream_flush(&os,&og);
140 fwrite(og.header,1,og.header_len,stdout);
141 fwrite(og.body,1,og.body_len,stdout);
148 long bytes=fread(readbuffer,1,READ*4,stdin); /* stereo hardwired here */
151 /* end of file. this can be done implicitly in the mainline,
152 but it's easier to see here in non-clever fashion.
153 Tell the library we're at end of stream so that it can handle
154 the last frame and mark end of stream in the output properly */
155 vorbis_analysis_wrote(&vd,0);
160 /* expose the buffer to submit data */
161 float **buffer=vorbis_analysis_buffer(&vd,READ);
163 /* uninterleave samples */
164 for(i=0;i<bytes/4;i++){
165 buffer[0][i]=((readbuffer[i*4+1]<<8)|
166 (0x00ff&(int)readbuffer[i*4]))/32768.f;
167 buffer[1][i]=((readbuffer[i*4+3]<<8)|
168 (0x00ff&(int)readbuffer[i*4+2]))/32768.f;
171 /* tell the library how much we actually submitted */
172 vorbis_analysis_wrote(&vd,i);
175 /* vorbis does some data preanalysis, then divvies up blocks for
176 more involved (potentially parallel) processing. Get a single
177 block for encoding now */
178 while(vorbis_analysis_blockout(&vd,&vb)==1){
180 /* analysis, assume we want to use bitrate management */
181 vorbis_analysis(&vb,NULL);
182 vorbis_bitrate_addblock(&vb);
184 while(vorbis_bitrate_flushpacket(&vd,&op)){
186 /* weld the packet into the bitstream */
187 ogg_stream_packetin(&os,&op);
189 /* write out pages (if any) */
191 int result=ogg_stream_pageout(&os,&og);
193 fwrite(og.header,1,og.header_len,stdout);
194 fwrite(og.body,1,og.body_len,stdout);
196 /* this could be set above, but for illustrative purposes, I do
197 it here (to show that vorbis does know where the stream ends) */
199 if(ogg_page_eos(&og))eos=1;
205 /* clean up and exit. vorbis_info_clear() must be called last */
207 ogg_stream_clear(&os);
208 vorbis_block_clear(&vb);
209 vorbis_dsp_clear(&vd);
210 vorbis_comment_clear(&vc);
211 vorbis_info_clear(&vi);
213 /* ogg_page and ogg_packet structs always point to storage in
214 libvorbis. They're never freed or manipulated directly */
216 fprintf(stderr,"Done.\n");