cannam@86: /********************************************************************
cannam@86:  *                                                                  *
cannam@86:  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
cannam@86:  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
cannam@86:  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
cannam@86:  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
cannam@86:  *                                                                  *
cannam@86:  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
cannam@86:  * by the Xiph.Org Foundation http://www.xiph.org/                  *
cannam@86:  *                                                                  *
cannam@86:  ********************************************************************
cannam@86: 
cannam@86:  function: floor backend 0 implementation
cannam@86:  last mod: $Id: floor0.c 18184 2012-02-03 20:55:12Z xiphmont $
cannam@86: 
cannam@86:  ********************************************************************/
cannam@86: 
cannam@86: #include <stdlib.h>
cannam@86: #include <string.h>
cannam@86: #include <math.h>
cannam@86: #include <ogg/ogg.h>
cannam@86: #include "vorbis/codec.h"
cannam@86: #include "codec_internal.h"
cannam@86: #include "registry.h"
cannam@86: #include "lpc.h"
cannam@86: #include "lsp.h"
cannam@86: #include "codebook.h"
cannam@86: #include "scales.h"
cannam@86: #include "misc.h"
cannam@86: #include "os.h"
cannam@86: 
cannam@86: #include "misc.h"
cannam@86: #include <stdio.h>
cannam@86: 
cannam@86: typedef struct {
cannam@86:   int ln;
cannam@86:   int  m;
cannam@86:   int **linearmap;
cannam@86:   int  n[2];
cannam@86: 
cannam@86:   vorbis_info_floor0 *vi;
cannam@86: 
cannam@86:   long bits;
cannam@86:   long frames;
cannam@86: } vorbis_look_floor0;
cannam@86: 
cannam@86: 
cannam@86: /***********************************************/
cannam@86: 
cannam@86: static void floor0_free_info(vorbis_info_floor *i){
cannam@86:   vorbis_info_floor0 *info=(vorbis_info_floor0 *)i;
cannam@86:   if(info){
cannam@86:     memset(info,0,sizeof(*info));
cannam@86:     _ogg_free(info);
cannam@86:   }
cannam@86: }
cannam@86: 
cannam@86: static void floor0_free_look(vorbis_look_floor *i){
cannam@86:   vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
cannam@86:   if(look){
cannam@86: 
cannam@86:     if(look->linearmap){
cannam@86: 
cannam@86:       if(look->linearmap[0])_ogg_free(look->linearmap[0]);
cannam@86:       if(look->linearmap[1])_ogg_free(look->linearmap[1]);
cannam@86: 
cannam@86:       _ogg_free(look->linearmap);
cannam@86:     }
cannam@86:     memset(look,0,sizeof(*look));
cannam@86:     _ogg_free(look);
cannam@86:   }
cannam@86: }
cannam@86: 
cannam@86: static vorbis_info_floor *floor0_unpack (vorbis_info *vi,oggpack_buffer *opb){
cannam@86:   codec_setup_info     *ci=vi->codec_setup;
cannam@86:   int j;
cannam@86: 
cannam@86:   vorbis_info_floor0 *info=_ogg_malloc(sizeof(*info));
cannam@86:   info->order=oggpack_read(opb,8);
cannam@86:   info->rate=oggpack_read(opb,16);
cannam@86:   info->barkmap=oggpack_read(opb,16);
cannam@86:   info->ampbits=oggpack_read(opb,6);
cannam@86:   info->ampdB=oggpack_read(opb,8);
cannam@86:   info->numbooks=oggpack_read(opb,4)+1;
cannam@86: 
cannam@86:   if(info->order<1)goto err_out;
cannam@86:   if(info->rate<1)goto err_out;
cannam@86:   if(info->barkmap<1)goto err_out;
cannam@86:   if(info->numbooks<1)goto err_out;
cannam@86: 
cannam@86:   for(j=0;j<info->numbooks;j++){
cannam@86:     info->books[j]=oggpack_read(opb,8);
cannam@86:     if(info->books[j]<0 || info->books[j]>=ci->books)goto err_out;
cannam@86:     if(ci->book_param[info->books[j]]->maptype==0)goto err_out;
cannam@86:     if(ci->book_param[info->books[j]]->dim<1)goto err_out;
cannam@86:   }
cannam@86:   return(info);
cannam@86: 
cannam@86:  err_out:
cannam@86:   floor0_free_info(info);
cannam@86:   return(NULL);
cannam@86: }
cannam@86: 
cannam@86: /* initialize Bark scale and normalization lookups.  We could do this
cannam@86:    with static tables, but Vorbis allows a number of possible
cannam@86:    combinations, so it's best to do it computationally.
cannam@86: 
cannam@86:    The below is authoritative in terms of defining scale mapping.
cannam@86:    Note that the scale depends on the sampling rate as well as the
cannam@86:    linear block and mapping sizes */
cannam@86: 
cannam@86: static void floor0_map_lazy_init(vorbis_block      *vb,
cannam@86:                                  vorbis_info_floor *infoX,
cannam@86:                                  vorbis_look_floor0 *look){
cannam@86:   if(!look->linearmap[vb->W]){
cannam@86:     vorbis_dsp_state   *vd=vb->vd;
cannam@86:     vorbis_info        *vi=vd->vi;
cannam@86:     codec_setup_info   *ci=vi->codec_setup;
cannam@86:     vorbis_info_floor0 *info=(vorbis_info_floor0 *)infoX;
cannam@86:     int W=vb->W;
cannam@86:     int n=ci->blocksizes[W]/2,j;
cannam@86: 
cannam@86:     /* we choose a scaling constant so that:
cannam@86:        floor(bark(rate/2-1)*C)=mapped-1
cannam@86:      floor(bark(rate/2)*C)=mapped */
cannam@86:     float scale=look->ln/toBARK(info->rate/2.f);
cannam@86: 
cannam@86:     /* the mapping from a linear scale to a smaller bark scale is
cannam@86:        straightforward.  We do *not* make sure that the linear mapping
cannam@86:        does not skip bark-scale bins; the decoder simply skips them and
cannam@86:        the encoder may do what it wishes in filling them.  They're
cannam@86:        necessary in some mapping combinations to keep the scale spacing
cannam@86:        accurate */
cannam@86:     look->linearmap[W]=_ogg_malloc((n+1)*sizeof(**look->linearmap));
cannam@86:     for(j=0;j<n;j++){
cannam@86:       int val=floor( toBARK((info->rate/2.f)/n*j)
cannam@86:                      *scale); /* bark numbers represent band edges */
cannam@86:       if(val>=look->ln)val=look->ln-1; /* guard against the approximation */
cannam@86:       look->linearmap[W][j]=val;
cannam@86:     }
cannam@86:     look->linearmap[W][j]=-1;
cannam@86:     look->n[W]=n;
cannam@86:   }
cannam@86: }
cannam@86: 
cannam@86: static vorbis_look_floor *floor0_look(vorbis_dsp_state *vd,
cannam@86:                                       vorbis_info_floor *i){
cannam@86:   vorbis_info_floor0 *info=(vorbis_info_floor0 *)i;
cannam@86:   vorbis_look_floor0 *look=_ogg_calloc(1,sizeof(*look));
cannam@86:   look->m=info->order;
cannam@86:   look->ln=info->barkmap;
cannam@86:   look->vi=info;
cannam@86: 
cannam@86:   look->linearmap=_ogg_calloc(2,sizeof(*look->linearmap));
cannam@86: 
cannam@86:   return look;
cannam@86: }
cannam@86: 
cannam@86: static void *floor0_inverse1(vorbis_block *vb,vorbis_look_floor *i){
cannam@86:   vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
cannam@86:   vorbis_info_floor0 *info=look->vi;
cannam@86:   int j,k;
cannam@86: 
cannam@86:   int ampraw=oggpack_read(&vb->opb,info->ampbits);
cannam@86:   if(ampraw>0){ /* also handles the -1 out of data case */
cannam@86:     long maxval=(1<<info->ampbits)-1;
cannam@86:     float amp=(float)ampraw/maxval*info->ampdB;
cannam@86:     int booknum=oggpack_read(&vb->opb,_ilog(info->numbooks));
cannam@86: 
cannam@86:     if(booknum!=-1 && booknum<info->numbooks){ /* be paranoid */
cannam@86:       codec_setup_info  *ci=vb->vd->vi->codec_setup;
cannam@86:       codebook *b=ci->fullbooks+info->books[booknum];
cannam@86:       float last=0.f;
cannam@86: 
cannam@86:       /* the additional b->dim is a guard against any possible stack
cannam@86:          smash; b->dim is provably more than we can overflow the
cannam@86:          vector */
cannam@86:       float *lsp=_vorbis_block_alloc(vb,sizeof(*lsp)*(look->m+b->dim+1));
cannam@86: 
cannam@86:       if(vorbis_book_decodev_set(b,lsp,&vb->opb,look->m)==-1)goto eop;
cannam@86:       for(j=0;j<look->m;){
cannam@86:         for(k=0;j<look->m && k<b->dim;k++,j++)lsp[j]+=last;
cannam@86:         last=lsp[j-1];
cannam@86:       }
cannam@86: 
cannam@86:       lsp[look->m]=amp;
cannam@86:       return(lsp);
cannam@86:     }
cannam@86:   }
cannam@86:  eop:
cannam@86:   return(NULL);
cannam@86: }
cannam@86: 
cannam@86: static int floor0_inverse2(vorbis_block *vb,vorbis_look_floor *i,
cannam@86:                            void *memo,float *out){
cannam@86:   vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
cannam@86:   vorbis_info_floor0 *info=look->vi;
cannam@86: 
cannam@86:   floor0_map_lazy_init(vb,info,look);
cannam@86: 
cannam@86:   if(memo){
cannam@86:     float *lsp=(float *)memo;
cannam@86:     float amp=lsp[look->m];
cannam@86: 
cannam@86:     /* take the coefficients back to a spectral envelope curve */
cannam@86:     vorbis_lsp_to_curve(out,
cannam@86:                         look->linearmap[vb->W],
cannam@86:                         look->n[vb->W],
cannam@86:                         look->ln,
cannam@86:                         lsp,look->m,amp,(float)info->ampdB);
cannam@86:     return(1);
cannam@86:   }
cannam@86:   memset(out,0,sizeof(*out)*look->n[vb->W]);
cannam@86:   return(0);
cannam@86: }
cannam@86: 
cannam@86: /* export hooks */
cannam@86: const vorbis_func_floor floor0_exportbundle={
cannam@86:   NULL,&floor0_unpack,&floor0_look,&floor0_free_info,
cannam@86:   &floor0_free_look,&floor0_inverse1,&floor0_inverse2
cannam@86: };