Chris@1: /******************************************************************** Chris@1: * * Chris@1: * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * Chris@1: * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * Chris@1: * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * Chris@1: * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * Chris@1: * * Chris@1: * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 * Chris@1: * by the Xiph.Org Foundation http://www.xiph.org/ * Chris@1: * * Chris@1: ******************************************************************** Chris@1: Chris@1: function: single-block PCM synthesis Chris@1: last mod: $Id: synthesis.c 17474 2010-09-30 03:41:41Z gmaxwell $ Chris@1: Chris@1: ********************************************************************/ Chris@1: Chris@1: #include Chris@1: #include Chris@1: #include "vorbis/codec.h" Chris@1: #include "codec_internal.h" Chris@1: #include "registry.h" Chris@1: #include "misc.h" Chris@1: #include "os.h" Chris@1: Chris@1: int vorbis_synthesis(vorbis_block *vb,ogg_packet *op){ Chris@1: vorbis_dsp_state *vd= vb ? vb->vd : 0; Chris@1: private_state *b= vd ? vd->backend_state : 0; Chris@1: vorbis_info *vi= vd ? vd->vi : 0; Chris@1: codec_setup_info *ci= vi ? vi->codec_setup : 0; Chris@1: oggpack_buffer *opb=vb ? &vb->opb : 0; Chris@1: int type,mode,i; Chris@1: Chris@1: if (!vd || !b || !vi || !ci || !opb) { Chris@1: return OV_EBADPACKET; Chris@1: } Chris@1: Chris@1: /* first things first. Make sure decode is ready */ Chris@1: _vorbis_block_ripcord(vb); Chris@1: oggpack_readinit(opb,op->packet,op->bytes); Chris@1: Chris@1: /* Check the packet type */ Chris@1: if(oggpack_read(opb,1)!=0){ Chris@1: /* Oops. This is not an audio data packet */ Chris@1: return(OV_ENOTAUDIO); Chris@1: } Chris@1: Chris@1: /* read our mode and pre/post windowsize */ Chris@1: mode=oggpack_read(opb,b->modebits); Chris@1: if(mode==-1){ Chris@1: return(OV_EBADPACKET); Chris@1: } Chris@1: Chris@1: vb->mode=mode; Chris@1: if(!ci->mode_param[mode]){ Chris@1: return(OV_EBADPACKET); Chris@1: } Chris@1: Chris@1: vb->W=ci->mode_param[mode]->blockflag; Chris@1: if(vb->W){ Chris@1: Chris@1: /* this doesn;t get mapped through mode selection as it's used Chris@1: only for window selection */ Chris@1: vb->lW=oggpack_read(opb,1); Chris@1: vb->nW=oggpack_read(opb,1); Chris@1: if(vb->nW==-1){ Chris@1: return(OV_EBADPACKET); Chris@1: } Chris@1: }else{ Chris@1: vb->lW=0; Chris@1: vb->nW=0; Chris@1: } Chris@1: Chris@1: /* more setup */ Chris@1: vb->granulepos=op->granulepos; Chris@1: vb->sequence=op->packetno; Chris@1: vb->eofflag=op->e_o_s; Chris@1: Chris@1: /* alloc pcm passback storage */ Chris@1: vb->pcmend=ci->blocksizes[vb->W]; Chris@1: vb->pcm=_vorbis_block_alloc(vb,sizeof(*vb->pcm)*vi->channels); Chris@1: for(i=0;ichannels;i++) Chris@1: vb->pcm[i]=_vorbis_block_alloc(vb,vb->pcmend*sizeof(*vb->pcm[i])); Chris@1: Chris@1: /* unpack_header enforces range checking */ Chris@1: type=ci->map_type[ci->mode_param[mode]->mapping]; Chris@1: Chris@1: return(_mapping_P[type]->inverse(vb,ci->map_param[ci->mode_param[mode]-> Chris@1: mapping])); Chris@1: } Chris@1: Chris@1: /* used to track pcm position without actually performing decode. Chris@1: Useful for sequential 'fast forward' */ Chris@1: int vorbis_synthesis_trackonly(vorbis_block *vb,ogg_packet *op){ Chris@1: vorbis_dsp_state *vd=vb->vd; Chris@1: private_state *b=vd->backend_state; Chris@1: vorbis_info *vi=vd->vi; Chris@1: codec_setup_info *ci=vi->codec_setup; Chris@1: oggpack_buffer *opb=&vb->opb; Chris@1: int mode; Chris@1: Chris@1: /* first things first. Make sure decode is ready */ Chris@1: _vorbis_block_ripcord(vb); Chris@1: oggpack_readinit(opb,op->packet,op->bytes); Chris@1: Chris@1: /* Check the packet type */ Chris@1: if(oggpack_read(opb,1)!=0){ Chris@1: /* Oops. This is not an audio data packet */ Chris@1: return(OV_ENOTAUDIO); Chris@1: } Chris@1: Chris@1: /* read our mode and pre/post windowsize */ Chris@1: mode=oggpack_read(opb,b->modebits); Chris@1: if(mode==-1)return(OV_EBADPACKET); Chris@1: Chris@1: vb->mode=mode; Chris@1: if(!ci->mode_param[mode]){ Chris@1: return(OV_EBADPACKET); Chris@1: } Chris@1: Chris@1: vb->W=ci->mode_param[mode]->blockflag; Chris@1: if(vb->W){ Chris@1: vb->lW=oggpack_read(opb,1); Chris@1: vb->nW=oggpack_read(opb,1); Chris@1: if(vb->nW==-1) return(OV_EBADPACKET); Chris@1: }else{ Chris@1: vb->lW=0; Chris@1: vb->nW=0; Chris@1: } Chris@1: Chris@1: /* more setup */ Chris@1: vb->granulepos=op->granulepos; Chris@1: vb->sequence=op->packetno; Chris@1: vb->eofflag=op->e_o_s; Chris@1: Chris@1: /* no pcm */ Chris@1: vb->pcmend=0; Chris@1: vb->pcm=NULL; Chris@1: Chris@1: return(0); Chris@1: } Chris@1: Chris@1: long vorbis_packet_blocksize(vorbis_info *vi,ogg_packet *op){ Chris@1: codec_setup_info *ci=vi->codec_setup; Chris@1: oggpack_buffer opb; Chris@1: int mode; Chris@1: Chris@1: oggpack_readinit(&opb,op->packet,op->bytes); Chris@1: Chris@1: /* Check the packet type */ Chris@1: if(oggpack_read(&opb,1)!=0){ Chris@1: /* Oops. This is not an audio data packet */ Chris@1: return(OV_ENOTAUDIO); Chris@1: } Chris@1: Chris@1: { Chris@1: int modebits=0; Chris@1: int v=ci->modes; Chris@1: while(v>1){ Chris@1: modebits++; Chris@1: v>>=1; Chris@1: } Chris@1: Chris@1: /* read our mode and pre/post windowsize */ Chris@1: mode=oggpack_read(&opb,modebits); Chris@1: } Chris@1: if(mode==-1)return(OV_EBADPACKET); Chris@1: return(ci->blocksizes[ci->mode_param[mode]->blockflag]); Chris@1: } Chris@1: Chris@1: int vorbis_synthesis_halfrate(vorbis_info *vi,int flag){ Chris@1: /* set / clear half-sample-rate mode */ Chris@1: codec_setup_info *ci=vi->codec_setup; Chris@1: Chris@1: /* right now, our MDCT can't handle < 64 sample windows. */ Chris@1: if(ci->blocksizes[0]<=64 && flag)return -1; Chris@1: ci->halfrate_flag=(flag?1:0); Chris@1: return 0; Chris@1: } Chris@1: Chris@1: int vorbis_synthesis_halfrate_p(vorbis_info *vi){ Chris@1: codec_setup_info *ci=vi->codec_setup; Chris@1: return ci->halfrate_flag; Chris@1: }