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authorAki <please@ignore.pl>2021-09-29 22:52:49 +0200
committerAki <please@ignore.pl>2021-09-29 22:52:49 +0200
commit760f65d35df281b04d99843958623d99ab35dcaf (patch)
tree76f6f05695822256bbf8097fa0aa6b5d2a34369b /vorbis/examples/encoder_example.c
parentbdb934044a10bcccdea4ae5e9b067a2e764e0e7f (diff)
parent74f4b1bc3b627ba4c7e03498234d88cacdfbe97b (diff)
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Merge commit '74f4b1bc3b627ba4c7e03498234d88cacdfbe97b' as 'vorbis'
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+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2007 *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function: simple example encoder
+
+ ********************************************************************/
+
+/* takes a stereo 16bit 44.1kHz WAV file from stdin and encodes it into
+ a Vorbis bitstream */
+
+/* Note that this is POSIX, not ANSI, code */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <math.h>
+#include <vorbis/vorbisenc.h>
+
+#ifdef _WIN32 /* We need the following two to set stdin/stdout to binary */
+#include <io.h>
+#include <fcntl.h>
+#endif
+
+#if defined(__MACOS__) && defined(__MWERKS__)
+#include <console.h> /* CodeWarrior's Mac "command-line" support */
+#endif
+
+#define READ 1024
+signed char readbuffer[READ*4+44]; /* out of the data segment, not the stack */
+
+int main(){
+ ogg_stream_state os; /* take physical pages, weld into a logical
+ stream of packets */
+ ogg_page og; /* one Ogg bitstream page. Vorbis packets are inside */
+ ogg_packet op; /* one raw packet of data for decode */
+
+ vorbis_info vi; /* struct that stores all the static vorbis bitstream
+ settings */
+ vorbis_comment vc; /* struct that stores all the user comments */
+
+ vorbis_dsp_state vd; /* central working state for the packet->PCM decoder */
+ vorbis_block vb; /* local working space for packet->PCM decode */
+
+ int eos=0,ret;
+ int i, founddata;
+
+#if defined(macintosh) && defined(__MWERKS__)
+ int argc = 0;
+ char **argv = NULL;
+ argc = ccommand(&argv); /* get a "command line" from the Mac user */
+ /* this also lets the user set stdin and stdout */
+#endif
+
+ /* we cheat on the WAV header; we just bypass 44 bytes (simplest WAV
+ header is 44 bytes) and assume that the data is 44.1khz, stereo, 16 bit
+ little endian pcm samples. This is just an example, after all. */
+
+#ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */
+ /* if we were reading/writing a file, it would also need to in
+ binary mode, eg, fopen("file.wav","wb"); */
+ /* Beware the evil ifdef. We avoid these where we can, but this one we
+ cannot. Don't add any more, you'll probably go to hell if you do. */
+ _setmode( _fileno( stdin ), _O_BINARY );
+ _setmode( _fileno( stdout ), _O_BINARY );
+#endif
+
+
+ /* we cheat on the WAV header; we just bypass the header and never
+ verify that it matches 16bit/stereo/44.1kHz. This is just an
+ example, after all. */
+
+ readbuffer[0] = '\0';
+ for (i=0, founddata=0; i<30 && ! feof(stdin) && ! ferror(stdin); i++)
+ {
+ fread(readbuffer,1,2,stdin);
+
+ if ( ! strncmp((char*)readbuffer, "da", 2) ){
+ founddata = 1;
+ fread(readbuffer,1,6,stdin);
+ break;
+ }
+ }
+
+ /********** Encode setup ************/
+
+ vorbis_info_init(&vi);
+
+ /* choose an encoding mode. A few possibilities commented out, one
+ actually used: */
+
+ /*********************************************************************
+ Encoding using a VBR quality mode. The usable range is -.1
+ (lowest quality, smallest file) to 1. (highest quality, largest file).
+ Example quality mode .4: 44kHz stereo coupled, roughly 128kbps VBR
+
+ ret = vorbis_encode_init_vbr(&vi,2,44100,.4);
+
+ ---------------------------------------------------------------------
+
+ Encoding using an average bitrate mode (ABR).
+ example: 44kHz stereo coupled, average 128kbps VBR
+
+ ret = vorbis_encode_init(&vi,2,44100,-1,128000,-1);
+
+ ---------------------------------------------------------------------
+
+ Encode using a quality mode, but select that quality mode by asking for
+ an approximate bitrate. This is not ABR, it is true VBR, but selected
+ using the bitrate interface, and then turning bitrate management off:
+
+ ret = ( vorbis_encode_setup_managed(&vi,2,44100,-1,128000,-1) ||
+ vorbis_encode_ctl(&vi,OV_ECTL_RATEMANAGE2_SET,NULL) ||
+ vorbis_encode_setup_init(&vi));
+
+ *********************************************************************/
+
+ ret=vorbis_encode_init_vbr(&vi,2,44100,0.1);
+
+ /* do not continue if setup failed; this can happen if we ask for a
+ mode that libVorbis does not support (eg, too low a bitrate, etc,
+ will return 'OV_EIMPL') */
+
+ if(ret)exit(1);
+
+ /* add a comment */
+ vorbis_comment_init(&vc);
+ vorbis_comment_add_tag(&vc,"ENCODER","encoder_example.c");
+
+ /* set up the analysis state and auxiliary encoding storage */
+ vorbis_analysis_init(&vd,&vi);
+ vorbis_block_init(&vd,&vb);
+
+ /* set up our packet->stream encoder */
+ /* pick a random serial number; that way we can more likely build
+ chained streams just by concatenation */
+ srand(time(NULL));
+ ogg_stream_init(&os,rand());
+
+ /* Vorbis streams begin with three headers; the initial header (with
+ most of the codec setup parameters) which is mandated by the Ogg
+ bitstream spec. The second header holds any comment fields. The
+ third header holds the bitstream codebook. We merely need to
+ make the headers, then pass them to libvorbis one at a time;
+ libvorbis handles the additional Ogg bitstream constraints */
+
+ {
+ ogg_packet header;
+ ogg_packet header_comm;
+ ogg_packet header_code;
+
+ vorbis_analysis_headerout(&vd,&vc,&header,&header_comm,&header_code);
+ ogg_stream_packetin(&os,&header); /* automatically placed in its own
+ page */
+ ogg_stream_packetin(&os,&header_comm);
+ ogg_stream_packetin(&os,&header_code);
+
+ /* This ensures the actual
+ * audio data will start on a new page, as per spec
+ */
+ while(!eos){
+ int result=ogg_stream_flush(&os,&og);
+ if(result==0)break;
+ fwrite(og.header,1,og.header_len,stdout);
+ fwrite(og.body,1,og.body_len,stdout);
+ }
+
+ }
+
+ while(!eos){
+ long i;
+ long bytes=fread(readbuffer,1,READ*4,stdin); /* stereo hardwired here */
+
+ if(bytes==0){
+ /* end of file. this can be done implicitly in the mainline,
+ but it's easier to see here in non-clever fashion.
+ Tell the library we're at end of stream so that it can handle
+ the last frame and mark end of stream in the output properly */
+ vorbis_analysis_wrote(&vd,0);
+
+ }else{
+ /* data to encode */
+
+ /* expose the buffer to submit data */
+ float **buffer=vorbis_analysis_buffer(&vd,READ);
+
+ /* uninterleave samples */
+ for(i=0;i<bytes/4;i++){
+ buffer[0][i]=((readbuffer[i*4+1]<<8)|
+ (0x00ff&(int)readbuffer[i*4]))/32768.f;
+ buffer[1][i]=((readbuffer[i*4+3]<<8)|
+ (0x00ff&(int)readbuffer[i*4+2]))/32768.f;
+ }
+
+ /* tell the library how much we actually submitted */
+ vorbis_analysis_wrote(&vd,i);
+ }
+
+ /* vorbis does some data preanalysis, then divvies up blocks for
+ more involved (potentially parallel) processing. Get a single
+ block for encoding now */
+ while(vorbis_analysis_blockout(&vd,&vb)==1){
+
+ /* analysis, assume we want to use bitrate management */
+ vorbis_analysis(&vb,NULL);
+ vorbis_bitrate_addblock(&vb);
+
+ while(vorbis_bitrate_flushpacket(&vd,&op)){
+
+ /* weld the packet into the bitstream */
+ ogg_stream_packetin(&os,&op);
+
+ /* write out pages (if any) */
+ while(!eos){
+ int result=ogg_stream_pageout(&os,&og);
+ if(result==0)break;
+ fwrite(og.header,1,og.header_len,stdout);
+ fwrite(og.body,1,og.body_len,stdout);
+
+ /* this could be set above, but for illustrative purposes, I do
+ it here (to show that vorbis does know where the stream ends) */
+
+ if(ogg_page_eos(&og))eos=1;
+ }
+ }
+ }
+ }
+
+ /* clean up and exit. vorbis_info_clear() must be called last */
+
+ ogg_stream_clear(&os);
+ vorbis_block_clear(&vb);
+ vorbis_dsp_clear(&vd);
+ vorbis_comment_clear(&vc);
+ vorbis_info_clear(&vi);
+
+ /* ogg_page and ogg_packet structs always point to storage in
+ libvorbis. They're never freed or manipulated directly */
+
+ fprintf(stderr,"Done.\n");
+ return(0);
+}