1 /********************************************************************
3 * THIS FILE IS PART OF THE Ogg Vorbis SOFTWARE CODEC SOURCE CODE. *
4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
5 * THE GNU PUBLIC LICENSE 2, WHICH IS INCLUDED WITH THIS SOURCE. *
6 * PLEASE READ THESE TERMS DISTRIBUTING. *
8 * THE OggSQUISH SOURCE CODE IS (C) COPYRIGHT 1994-2000 *
9 * by Monty <monty@xiph.org> and The XIPHOPHORUS Company *
10 * http://www.xiph.org/ *
12 ********************************************************************
14 function: simple example encoder
15 last mod: $Id: encoder_example.c,v 1.13 2000/08/15 14:01:02 xiphmont Exp $
17 ********************************************************************/
19 /* takes a stereo 16bit 44.1kHz WAV file from stdin and encodes it into
22 /* Note that this is POSIX, not ANSI, code */
28 #include "vorbis/mode_C.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 */
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 );
76 fread(readbuffer,1,44,stdin);
78 /********** Encode setup ************/
80 /* choose an encoding mode */
81 /* (mode 0: 44kHz stereo uncoupled, roughly 128kbps VBR) */
85 vorbis_comment_init(&vc);
86 vorbis_comment_add(&vc,"Track encoded by encoder_example.c");
88 /* set up the analysis state and auxiliary encoding storage */
89 vorbis_analysis_init(&vd,vi);
90 vorbis_block_init(&vd,&vb);
92 /* set up our packet->stream encoder */
93 /* pick a random serial number; that way we can more likely build
94 chained streams just by concatenation */
96 ogg_stream_init(&os,rand());
98 /* Vorbis streams begin with three headers; the initial header (with
99 most of the codec setup parameters) which is mandated by the Ogg
100 bitstream spec. The second header holds any comment fields. The
101 third header holds the bitstream codebook. We merely need to
102 make the headers, then pass them to libvorbis one at a time;
103 libvorbis handles the additional Ogg bitstream constraints */
107 ogg_packet header_comm;
108 ogg_packet header_code;
110 vorbis_analysis_headerout(&vd,&vc,&header,&header_comm,&header_code);
111 ogg_stream_packetin(&os,&header); /* automatically placed in its own
113 ogg_stream_packetin(&os,&header_comm);
114 ogg_stream_packetin(&os,&header_code);
116 /* no need to write out here. We'll get to that in the main loop */
121 long bytes=fread(readbuffer,1,READ*4,stdin); /* stereo hardwired here */
124 /* end of file. this can be done implicitly in the mainline,
125 but it's easier to see here in non-clever fashion.
126 Tell the library we're at end of stream so that it can handle
127 the last frame and mark end of stream in the output properly */
128 vorbis_analysis_wrote(&vd,0);
133 /* expose the buffer to submit data */
134 double **buffer=vorbis_analysis_buffer(&vd,READ);
136 /* uninterleave samples */
137 for(i=0;i<bytes/4;i++){
138 buffer[0][i]=((readbuffer[i*4+1]<<8)|
139 (0x00ff&(int)readbuffer[i*4]))/32768.;
140 buffer[1][i]=((readbuffer[i*4+3]<<8)|
141 (0x00ff&(int)readbuffer[i*4+2]))/32768.;
144 /* tell the library how much we actually submitted */
145 vorbis_analysis_wrote(&vd,i);
148 /* vorbis does some data preanalysis, then divvies up blocks for
149 more involved (potentially parallel) processing. Get a single
150 block for encoding now */
151 while(vorbis_analysis_blockout(&vd,&vb)==1){
154 vorbis_analysis(&vb,&op);
156 /* weld the packet into the bitstream */
157 ogg_stream_packetin(&os,&op);
159 /* write out pages (if any) */
161 int result=ogg_stream_pageout(&os,&og);
163 fwrite(og.header,1,og.header_len,stdout);
164 fwrite(og.body,1,og.body_len,stdout);
166 /* this could be set above, but for illustrative purposes, I do
167 it here (to show that vorbis does know where the stream ends) */
169 if(ogg_page_eos(&og))eos=1;
175 /* clean up and exit. vorbis_info_clear() must be called last */
177 ogg_stream_clear(&os);
178 vorbis_block_clear(&vb);
179 vorbis_dsp_clear(&vd);
181 /* ogg_page and ogg_packet structs always point to storage in
182 libvorbis. They're never freed or manipulated directly */
184 fprintf(stderr,"Done.\n");