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Diffstat (limited to 'examples/decoder_example.c')
| -rw-r--r-- | examples/decoder_example.c | 307 |
1 files changed, 0 insertions, 307 deletions
diff --git a/examples/decoder_example.c b/examples/decoder_example.c deleted file mode 100644 index e246bd24..00000000 --- a/examples/decoder_example.c +++ /dev/null @@ -1,307 +0,0 @@ -/******************************************************************** - * * - * 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 1994-2001 * - * by the XIPHOPHORUS Company http://www.xiph.org/ * - * * - ******************************************************************** - - function: simple example decoder - last mod: $Id: decoder_example.c,v 1.25 2002/01/22 08:06:05 xiphmont Exp $ - - ********************************************************************/ - -/* Takes a vorbis bitstream from stdin and writes raw stereo PCM to - stdout. Decodes simple and chained OggVorbis files from beginning - to end. Vorbisfile.a is somewhat more complex than the code below. */ - -/* Note that this is POSIX, not ANSI code */ - -#include <stdio.h> -#include <stdlib.h> -#include <math.h> -#include <vorbis/codec.h> - -#ifdef _WIN32 /* We need the following two to set stdin/stdout to binary */ -#include <io.h> -#include <fcntl.h> -#endif - -#if defined(macintosh) && defined(__MWERKS__) -#include <console.h> /* CodeWarrior's Mac "command-line" support */ -#endif - -ogg_int16_t convbuffer[4096]; /* take 8k out of the data segment, not the stack */ -int convsize=4096; - -extern void _VDBG_dump(void); - -int main(){ - ogg_sync_state oy; /* sync and verify incoming physical bitstream */ - 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 bitstream user comments */ - vorbis_dsp_state vd; /* central working state for the packet->PCM decoder */ - vorbis_block vb; /* local working space for packet->PCM decode */ - - char *buffer; - int bytes; - -#ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */ - /* 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 - -#if defined(macintosh) && defined(__MWERKS__) - { - int argc; - char **argv; - argc=ccommand(&argv); /* get a "command line" from the Mac user */ - /* this also lets the user set stdin and stdout */ - } -#endif - - /********** Decode setup ************/ - - ogg_sync_init(&oy); /* Now we can read pages */ - - while(1){ /* we repeat if the bitstream is chained */ - int eos=0; - int i; - - /* grab some data at the head of the stream. We want the first page - (which is guaranteed to be small and only contain the Vorbis - stream initial header) We need the first page to get the stream - serialno. */ - - /* submit a 4k block to libvorbis' Ogg layer */ - buffer=ogg_sync_buffer(&oy,4096); - bytes=fread(buffer,1,4096,stdin); - ogg_sync_wrote(&oy,bytes); - - /* Get the first page. */ - if(ogg_sync_pageout(&oy,&og)!=1){ - /* have we simply run out of data? If so, we're done. */ - if(bytes<4096)break; - - /* error case. Must not be Vorbis data */ - fprintf(stderr,"Input does not appear to be an Ogg bitstream.\n"); - exit(1); - } - - /* Get the serial number and set up the rest of decode. */ - /* serialno first; use it to set up a logical stream */ - ogg_stream_init(&os,ogg_page_serialno(&og)); - - /* extract the initial header from the first page and verify that the - Ogg bitstream is in fact Vorbis data */ - - /* I handle the initial header first instead of just having the code - read all three Vorbis headers at once because reading the initial - header is an easy way to identify a Vorbis bitstream and it's - useful to see that functionality seperated out. */ - - vorbis_info_init(&vi); - vorbis_comment_init(&vc); - if(ogg_stream_pagein(&os,&og)<0){ - /* error; stream version mismatch perhaps */ - fprintf(stderr,"Error reading first page of Ogg bitstream data.\n"); - exit(1); - } - - if(ogg_stream_packetout(&os,&op)!=1){ - /* no page? must not be vorbis */ - fprintf(stderr,"Error reading initial header packet.\n"); - exit(1); - } - - if(vorbis_synthesis_headerin(&vi,&vc,&op)<0){ - /* error case; not a vorbis header */ - fprintf(stderr,"This Ogg bitstream does not contain Vorbis " - "audio data.\n"); - exit(1); - } - - /* At this point, we're sure we're Vorbis. We've set up the logical - (Ogg) bitstream decoder. Get the comment and codebook headers and - set up the Vorbis decoder */ - - /* The next two packets in order are the comment and codebook headers. - They're likely large and may span multiple pages. Thus we reead - and submit data until we get our two pacakets, watching that no - pages are missing. If a page is missing, error out; losing a - header page is the only place where missing data is fatal. */ - - i=0; - while(i<2){ - while(i<2){ - int result=ogg_sync_pageout(&oy,&og); - if(result==0)break; /* Need more data */ - /* Don't complain about missing or corrupt data yet. We'll - catch it at the packet output phase */ - if(result==1){ - ogg_stream_pagein(&os,&og); /* we can ignore any errors here - as they'll also become apparent - at packetout */ - while(i<2){ - result=ogg_stream_packetout(&os,&op); - if(result==0)break; - if(result<0){ - /* Uh oh; data at some point was corrupted or missing! - We can't tolerate that in a header. Die. */ - fprintf(stderr,"Corrupt secondary header. Exiting.\n"); - exit(1); - } - vorbis_synthesis_headerin(&vi,&vc,&op); - i++; - } - } - } - /* no harm in not checking before adding more */ - buffer=ogg_sync_buffer(&oy,4096); - bytes=fread(buffer,1,4096,stdin); - if(bytes==0 && i<2){ - fprintf(stderr,"End of file before finding all Vorbis headers!\n"); - exit(1); - } - ogg_sync_wrote(&oy,bytes); - } - - /* Throw the comments plus a few lines about the bitstream we're - decoding */ - { - char **ptr=vc.user_comments; - while(*ptr){ - fprintf(stderr,"%s\n",*ptr); - ++ptr; - } - fprintf(stderr,"\nBitstream is %d channel, %ldHz\n",vi.channels,vi.rate); - fprintf(stderr,"Encoded by: %s\n\n",vc.vendor); - } - - convsize=4096/vi.channels; - - /* OK, got and parsed all three headers. Initialize the Vorbis - packet->PCM decoder. */ - vorbis_synthesis_init(&vd,&vi); /* central decode state */ - vorbis_block_init(&vd,&vb); /* local state for most of the decode - so multiple block decodes can - proceed in parallel. We could init - multiple vorbis_block structures - for vd here */ - - /* The rest is just a straight decode loop until end of stream */ - while(!eos){ - while(!eos){ - int result=ogg_sync_pageout(&oy,&og); - if(result==0)break; /* need more data */ - if(result<0){ /* missing or corrupt data at this page position */ - fprintf(stderr,"Corrupt or missing data in bitstream; " - "continuing...\n"); - }else{ - ogg_stream_pagein(&os,&og); /* can safely ignore errors at - this point */ - while(1){ - result=ogg_stream_packetout(&os,&op); - - if(result==0)break; /* need more data */ - if(result<0){ /* missing or corrupt data at this page position */ - /* no reason to complain; already complained above */ - }else{ - /* we have a packet. Decode it */ - float **pcm; - int samples; - - if(vorbis_synthesis(&vb,&op)==0) /* test for success! */ - vorbis_synthesis_blockin(&vd,&vb); - /* - - **pcm is a multichannel float vector. In stereo, for - example, pcm[0] is left, and pcm[1] is right. samples is - the size of each channel. Convert the float values - (-1.<=range<=1.) to whatever PCM format and write it out */ - - while((samples=vorbis_synthesis_pcmout(&vd,&pcm))>0){ - int j; - int clipflag=0; - int bout=(samples<convsize?samples:convsize); - - /* convert floats to 16 bit signed ints (host order) and - interleave */ - for(i=0;i<vi.channels;i++){ - ogg_int16_t *ptr=convbuffer+i; - float *mono=pcm[i]; - for(j=0;j<bout;j++){ -#if 1 - int val=mono[j]*32767.f; -#else /* optional dither */ - int val=mono[j]*32767.f+drand48()-0.5f; -#endif - /* might as well guard against clipping */ - if(val>32767){ - val=32767; - clipflag=1; - } - if(val<-32768){ - val=-32768; - clipflag=1; - } - *ptr=val; - ptr+=vi.channels; - } - } - - if(clipflag) - fprintf(stderr,"Clipping in frame %ld\n",(long)(vd.sequence)); - - - fwrite(convbuffer,2*vi.channels,bout,stdout); - - vorbis_synthesis_read(&vd,bout); /* tell libvorbis how - many samples we - actually consumed */ - } - } - } - if(ogg_page_eos(&og))eos=1; - } - } - if(!eos){ - buffer=ogg_sync_buffer(&oy,4096); - bytes=fread(buffer,1,4096,stdin); - ogg_sync_wrote(&oy,bytes); - if(bytes==0)eos=1; - } - } - - /* clean up this logical bitstream; before exit we see if we're - followed by another [chained] */ - - ogg_stream_clear(&os); - - /* ogg_page and ogg_packet structs always point to storage in - libvorbis. They're never freed or manipulated directly */ - - vorbis_block_clear(&vb); - vorbis_dsp_clear(&vd); - vorbis_comment_clear(&vc); - vorbis_info_clear(&vi); /* must be called last */ - } - - /* OK, clean up the framer */ - ogg_sync_clear(&oy); - - fprintf(stderr,"Done.\n"); - return(0); -} |