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-rw-r--r--tremor/floor0.c436
1 files changed, 436 insertions, 0 deletions
diff --git a/tremor/floor0.c b/tremor/floor0.c
new file mode 100644
index 0000000000..3ed57a561a
--- /dev/null
+++ b/tremor/floor0.c
@@ -0,0 +1,436 @@
+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggVorbis 'TREMOR' 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 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002 *
+ * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function: floor backend 0 implementation
+
+ ********************************************************************/
+
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include "ogg.h"
+#include "ivorbiscodec.h"
+#include "codec_internal.h"
+#include "registry.h"
+#include "codebook.h"
+#include "misc.h"
+#include "os.h"
+
+#define LSP_FRACBITS 14
+
+typedef struct {
+ long n;
+ int ln;
+ int m;
+ int *linearmap;
+
+ vorbis_info_floor0 *vi;
+ ogg_int32_t *lsp_look;
+
+} vorbis_look_floor0;
+
+/*************** LSP decode ********************/
+
+#include "lsp_lookup.h"
+
+/* interpolated 1./sqrt(p) where .5 <= a < 1. (.100000... to .111111...) in
+ 16.16 format
+ returns in m.8 format */
+
+static long ADJUST_SQRT2[2]={8192,5792};
+static inline ogg_int32_t vorbis_invsqlook_i(long a,long e){
+ long i=(a&0x7fff)>>(INVSQ_LOOKUP_I_SHIFT-1);
+ long d=a&INVSQ_LOOKUP_I_MASK; /* 0.10 */
+ long val=INVSQ_LOOKUP_I[i]- /* 1.16 */
+ ((INVSQ_LOOKUP_IDel[i]*d)>>INVSQ_LOOKUP_I_SHIFT); /* result 1.16 */
+ val*=ADJUST_SQRT2[e&1];
+ e=(e>>1)+21;
+ return(val>>e);
+}
+
+/* interpolated lookup based fromdB function, domain -140dB to 0dB only */
+/* a is in n.12 format */
+static inline ogg_int32_t vorbis_fromdBlook_i(long a){
+ int i=(-a)>>(12-FROMdB2_SHIFT);
+ if(i<0) return 0x7fffffff;
+ if(i>=(FROMdB_LOOKUP_SZ<<FROMdB_SHIFT))return 0;
+
+ return FROMdB_LOOKUP[i>>FROMdB_SHIFT] * FROMdB2_LOOKUP[i&FROMdB2_MASK];
+}
+
+/* interpolated lookup based cos function, domain 0 to PI only */
+/* a is in 0.16 format, where 0==0, 2^^16-1==PI, return 0.14 */
+static inline ogg_int32_t vorbis_coslook_i(long a){
+ int i=a>>COS_LOOKUP_I_SHIFT;
+ int d=a&COS_LOOKUP_I_MASK;
+ return COS_LOOKUP_I[i]- ((d*(COS_LOOKUP_I[i]-COS_LOOKUP_I[i+1]))>>
+ COS_LOOKUP_I_SHIFT);
+}
+
+/* interpolated lookup based cos function */
+/* a is in 0.16 format, where 0==0, 2^^16==PI, return .LSP_FRACBITS */
+static inline ogg_int32_t vorbis_coslook2_i(long a){
+ a=a&0x1ffff;
+
+ if(a>0x10000)a=0x20000-a;
+ {
+ int i=a>>COS_LOOKUP_I_SHIFT;
+ int d=a&COS_LOOKUP_I_MASK;
+ a=((COS_LOOKUP_I[i]<<COS_LOOKUP_I_SHIFT)-
+ d*(COS_LOOKUP_I[i]-COS_LOOKUP_I[i+1]))>>
+ (COS_LOOKUP_I_SHIFT-LSP_FRACBITS+14);
+ }
+
+ return(a);
+}
+
+static const int barklook[28]={
+ 0,100,200,301, 405,516,635,766,
+ 912,1077,1263,1476, 1720,2003,2333,2721,
+ 3184,3742,4428,5285, 6376,7791,9662,12181,
+ 15624,20397,27087,36554
+};
+
+/* used in init only; interpolate the long way */
+static inline ogg_int32_t toBARK(int n){
+ int i;
+ for(i=0;i<27;i++)
+ if(n>=barklook[i] && n<barklook[i+1])break;
+
+ if(i==27){
+ return 27<<15;
+ }else{
+ int gap=barklook[i+1]-barklook[i];
+ int del=n-barklook[i];
+
+ return((i<<15)+((del<<15)/gap));
+ }
+}
+
+static const unsigned char MLOOP_1[64]={
+ 0,10,11,11, 12,12,12,12, 13,13,13,13, 13,13,13,13,
+ 14,14,14,14, 14,14,14,14, 14,14,14,14, 14,14,14,14,
+ 15,15,15,15, 15,15,15,15, 15,15,15,15, 15,15,15,15,
+ 15,15,15,15, 15,15,15,15, 15,15,15,15, 15,15,15,15,
+};
+
+static const unsigned char MLOOP_2[64]={
+ 0,4,5,5, 6,6,6,6, 7,7,7,7, 7,7,7,7,
+ 8,8,8,8, 8,8,8,8, 8,8,8,8, 8,8,8,8,
+ 9,9,9,9, 9,9,9,9, 9,9,9,9, 9,9,9,9,
+ 9,9,9,9, 9,9,9,9, 9,9,9,9, 9,9,9,9,
+};
+
+static const unsigned char MLOOP_3[8]={0,1,2,2,3,3,3,3};
+
+void vorbis_lsp_to_curve(ogg_int32_t *curve,int *map,int n,int ln,
+ ogg_int32_t *lsp,int m,
+ ogg_int32_t amp,
+ ogg_int32_t ampoffset,
+ ogg_int32_t *icos){
+
+ /* 0 <= m < 256 */
+
+ /* set up for using all int later */
+ int i;
+ int ampoffseti=ampoffset*4096;
+ int ampi=amp;
+ ogg_int32_t *ilsp=(ogg_int32_t *)alloca(m*sizeof(*ilsp));
+ /* lsp is in 8.24, range 0 to PI; coslook wants it in .16 0 to 1*/
+ for(i=0;i<m;i++){
+#ifndef _LOW_ACCURACY_
+ ogg_int32_t val=MULT32(lsp[i],0x517cc2);
+#else
+ ogg_int32_t val=((lsp[i]>>10)*0x517d)>>14;
+#endif
+
+ /* safeguard against a malicious stream */
+ if(val<0 || (val>>COS_LOOKUP_I_SHIFT)>=COS_LOOKUP_I_SZ){
+ memset(curve,0,sizeof(*curve)*n);
+ return;
+ }
+
+ ilsp[i]=vorbis_coslook_i(val);
+ }
+
+ i=0;
+ while(i<n){
+ int j,k=map[i];
+ ogg_uint32_t pi=46341; /* 2**-.5 in 0.16 */
+ ogg_uint32_t qi=46341;
+ ogg_int32_t qexp=0,shift;
+ ogg_int32_t wi=icos[k];
+
+#ifdef _V_LSP_MATH_ASM
+ lsp_loop_asm(&qi,&pi,&qexp,ilsp,wi,m);
+
+ pi=((pi*pi)>>16);
+ qi=((qi*qi)>>16);
+
+ if(m&1){
+ qexp= qexp*2-28*((m+1)>>1)+m;
+ pi*=(1<<14)-((wi*wi)>>14);
+ qi+=pi>>14;
+ }else{
+ qexp= qexp*2-13*m;
+
+ pi*=(1<<14)-wi;
+ qi*=(1<<14)+wi;
+
+ qi=(qi+pi)>>14;
+ }
+
+ if(qi&0xffff0000){ /* checks for 1.xxxxxxxxxxxxxxxx */
+ qi>>=1; qexp++;
+ }else
+ lsp_norm_asm(&qi,&qexp);
+
+#else
+
+ qi*=labs(ilsp[0]-wi);
+ pi*=labs(ilsp[1]-wi);
+
+ for(j=3;j<m;j+=2){
+ if(!(shift=MLOOP_1[(pi|qi)>>25]))
+ if(!(shift=MLOOP_2[(pi|qi)>>19]))
+ shift=MLOOP_3[(pi|qi)>>16];
+ qi=(qi>>shift)*labs(ilsp[j-1]-wi);
+ pi=(pi>>shift)*labs(ilsp[j]-wi);
+ qexp+=shift;
+ }
+ if(!(shift=MLOOP_1[(pi|qi)>>25]))
+ if(!(shift=MLOOP_2[(pi|qi)>>19]))
+ shift=MLOOP_3[(pi|qi)>>16];
+
+ /* pi,qi normalized collectively, both tracked using qexp */
+
+ if(m&1){
+ /* odd order filter; slightly assymetric */
+ /* the last coefficient */
+ qi=(qi>>shift)*labs(ilsp[j-1]-wi);
+ pi=(pi>>shift)<<14;
+ qexp+=shift;
+
+ if(!(shift=MLOOP_1[(pi|qi)>>25]))
+ if(!(shift=MLOOP_2[(pi|qi)>>19]))
+ shift=MLOOP_3[(pi|qi)>>16];
+
+ pi>>=shift;
+ qi>>=shift;
+ qexp+=shift-14*((m+1)>>1);
+
+ pi=((pi*pi)>>16);
+ qi=((qi*qi)>>16);
+ qexp=qexp*2+m;
+
+ pi*=(1<<14)-((wi*wi)>>14);
+ qi+=pi>>14;
+
+ }else{
+ /* even order filter; still symmetric */
+
+ /* p*=p(1-w), q*=q(1+w), let normalization drift because it isn't
+ worth tracking step by step */
+
+ pi>>=shift;
+ qi>>=shift;
+ qexp+=shift-7*m;
+
+ pi=((pi*pi)>>16);
+ qi=((qi*qi)>>16);
+ qexp=qexp*2+m;
+
+ pi*=(1<<14)-wi;
+ qi*=(1<<14)+wi;
+ qi=(qi+pi)>>14;
+
+ }
+
+
+ /* we've let the normalization drift because it wasn't important;
+ however, for the lookup, things must be normalized again. We
+ need at most one right shift or a number of left shifts */
+
+ if(qi&0xffff0000){ /* checks for 1.xxxxxxxxxxxxxxxx */
+ qi>>=1; qexp++;
+ }else
+ while(qi && !(qi&0x8000)){ /* checks for 0.0xxxxxxxxxxxxxxx or less*/
+ qi<<=1; qexp--;
+ }
+
+#endif
+
+ amp=vorbis_fromdBlook_i(ampi* /* n.4 */
+ vorbis_invsqlook_i(qi,qexp)-
+ /* m.8, m+n<=8 */
+ ampoffseti); /* 8.12[0] */
+
+#ifdef _LOW_ACCURACY_
+ amp>>=9;
+#endif
+ curve[i]= MULT31_SHIFT15(curve[i],amp);
+ while(map[++i]==k) curve[i]= MULT31_SHIFT15(curve[i],amp);
+ }
+}
+
+/*************** vorbis decode glue ************/
+
+static void floor0_free_info(vorbis_info_floor *i){
+ vorbis_info_floor0 *info=(vorbis_info_floor0 *)i;
+ if(info){
+ memset(info,0,sizeof(*info));
+ _ogg_free(info);
+ }
+}
+
+static void floor0_free_look(vorbis_look_floor *i){
+ vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
+ if(look){
+
+ if(look->linearmap)_ogg_free(look->linearmap);
+ if(look->lsp_look)_ogg_free(look->lsp_look);
+ memset(look,0,sizeof(*look));
+ _ogg_free(look);
+ }
+}
+
+static vorbis_info_floor *floor0_unpack (vorbis_info *vi,oggpack_buffer *opb){
+ codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
+ int j;
+
+ vorbis_info_floor0 *info=(vorbis_info_floor0 *)_ogg_malloc(sizeof(*info));
+ info->order=oggpack_read(opb,8);
+ info->rate=oggpack_read(opb,16);
+ info->barkmap=oggpack_read(opb,16);
+ info->ampbits=oggpack_read(opb,6);
+ info->ampdB=oggpack_read(opb,8);
+ info->numbooks=oggpack_read(opb,4)+1;
+
+ if(info->order<1)goto err_out;
+ if(info->rate<1)goto err_out;
+ if(info->barkmap<1)goto err_out;
+ if(info->numbooks<1)goto err_out;
+
+ for(j=0;j<info->numbooks;j++){
+ info->books[j]=oggpack_read(opb,8);
+ if(info->books[j]<0 || info->books[j]>=ci->books)goto err_out;
+ }
+ return(info);
+
+ err_out:
+ floor0_free_info(info);
+ return(NULL);
+}
+
+/* initialize Bark scale and normalization lookups. We could do this
+ with static tables, but Vorbis allows a number of possible
+ combinations, so it's best to do it computationally.
+
+ The below is authoritative in terms of defining scale mapping.
+ Note that the scale depends on the sampling rate as well as the
+ linear block and mapping sizes */
+
+static vorbis_look_floor *floor0_look (vorbis_dsp_state *vd,vorbis_info_mode *mi,
+ vorbis_info_floor *i){
+ int j;
+ ogg_int32_t scale;
+ vorbis_info *vi=vd->vi;
+ codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
+ vorbis_info_floor0 *info=(vorbis_info_floor0 *)i;
+ vorbis_look_floor0 *look=(vorbis_look_floor0 *)_ogg_calloc(1,sizeof(*look));
+ look->m=info->order;
+ look->n=ci->blocksizes[mi->blockflag]/2;
+ look->ln=info->barkmap;
+ look->vi=info;
+
+ /* the mapping from a linear scale to a smaller bark scale is
+ straightforward. We do *not* make sure that the linear mapping
+ does not skip bark-scale bins; the decoder simply skips them and
+ the encoder may do what it wishes in filling them. They're
+ necessary in some mapping combinations to keep the scale spacing
+ accurate */
+ look->linearmap=(int *)_ogg_malloc((look->n+1)*sizeof(*look->linearmap));
+ for(j=0;j<look->n;j++){
+
+ int val=(look->ln*
+ ((toBARK(info->rate/2*j/look->n)<<11)/toBARK(info->rate/2)))>>11;
+
+ if(val>=look->ln)val=look->ln-1; /* guard against the approximation */
+ look->linearmap[j]=val;
+ }
+ look->linearmap[j]=-1;
+
+ look->lsp_look=(ogg_int32_t *)_ogg_malloc(look->ln*sizeof(*look->lsp_look));
+ for(j=0;j<look->ln;j++)
+ look->lsp_look[j]=vorbis_coslook2_i(0x10000*j/look->ln);
+
+ return look;
+}
+
+static void *floor0_inverse1(vorbis_block *vb,vorbis_look_floor *i){
+ vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
+ vorbis_info_floor0 *info=look->vi;
+ int j,k;
+
+ int ampraw=oggpack_read(&vb->opb,info->ampbits);
+ if(ampraw>0){ /* also handles the -1 out of data case */
+ long maxval=(1<<info->ampbits)-1;
+ int amp=((ampraw*info->ampdB)<<4)/maxval;
+ int booknum=oggpack_read(&vb->opb,_ilog(info->numbooks));
+
+ if(booknum!=-1 && booknum<info->numbooks){ /* be paranoid */
+ codec_setup_info *ci=(codec_setup_info *)vb->vd->vi->codec_setup;
+ codebook *b=ci->fullbooks+info->books[booknum];
+ ogg_int32_t last=0;
+ ogg_int32_t *lsp=(ogg_int32_t *)_vorbis_block_alloc(vb,sizeof(*lsp)*(look->m+1));
+
+ for(j=0;j<look->m;j+=b->dim)
+ if(vorbis_book_decodev_set(b,lsp+j,&vb->opb,b->dim,-24)==-1)goto eop;
+ for(j=0;j<look->m;){
+ for(k=0;k<b->dim;k++,j++)lsp[j]+=last;
+ last=lsp[j-1];
+ }
+
+ lsp[look->m]=amp;
+ return(lsp);
+ }
+ }
+ eop:
+ return(NULL);
+}
+
+static int floor0_inverse2(vorbis_block *vb,vorbis_look_floor *i,
+ void *memo,ogg_int32_t *out){
+ vorbis_look_floor0 *look=(vorbis_look_floor0 *)i;
+ vorbis_info_floor0 *info=look->vi;
+
+ if(memo){
+ ogg_int32_t *lsp=(ogg_int32_t *)memo;
+ ogg_int32_t amp=lsp[look->m];
+
+ /* take the coefficients back to a spectral envelope curve */
+ vorbis_lsp_to_curve(out,look->linearmap,look->n,look->ln,
+ lsp,look->m,amp,info->ampdB,look->lsp_look);
+ return(1);
+ }
+ memset(out,0,sizeof(*out)*look->n);
+ return(0);
+}
+
+/* export hooks */
+vorbis_func_floor floor0_exportbundle={
+ &floor0_unpack,&floor0_look,&floor0_free_info,
+ &floor0_free_look,&floor0_inverse1,&floor0_inverse2
+};
+
+