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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <math.h>
#include <vorbis/vorbisenc.h>
#define READ_SZ 1024
signed char readbuffer[READ_SZ*4+44];
int main(int argc, char **argv)
{
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;
FILE *fin=NULL,*fout=NULL;
/* get input/output files from input */
if (argc != 3)
{
printf("%s [input] [output]\n",argv[0]);
exit(1);
}
fin = fopen(argv[1],"r");
if (fin == NULL)
{
printf("Cant open file %s\n", argv[1]);
exit(1);
}
fout = fopen(argv[2],"w");
if (fout == NULL)
{
printf("Cant open file %s\n", argv[2]);
exit(1);
}
/* encoding setup */
vorbis_info_init(&vi);
ret=vorbis_encode_init_vbr(&vi,2,44100,-.1);
if (ret)
{
printf("Cant setup encode mode\n");
exit(1);
}
/* add 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, fout);
fwrite(og.body, 1, og.body_len, fout);
}
}
while (!eos)
{
long i;
long bytes = fread(readbuffer, 1, READ_SZ*4, fin);
if (bytes == 0)
{
vorbis_analysis_wrote(&vd, 0);
} else
{
float **buffer = vorbis_analysis_buffer(&vd, READ_SZ);
/*do i need interleaver 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;
}
vorbis_analysis_wrote(&vd, bytes/4);
}
/* 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, fout);
fwrite(og.body, 1, og.body_len, fout);
/* 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;
}
}
}
}
ogg_stream_clear(&os);
vorbis_block_clear(&vb);
vorbis_dsp_clear(&vd);
vorbis_comment_clear(&vc);
vorbis_info_clear(&vi);
fclose(fout);
fclose(fin);
printf("Done\n");
return 0;
}
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