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Diffstat (limited to 'drivers/vorbis/mdct.c')
-rw-r--r-- | drivers/vorbis/mdct.c | 563 |
1 files changed, 0 insertions, 563 deletions
diff --git a/drivers/vorbis/mdct.c b/drivers/vorbis/mdct.c deleted file mode 100644 index 0816331805..0000000000 --- a/drivers/vorbis/mdct.c +++ /dev/null @@ -1,563 +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 1994-2009 * - * by the Xiph.Org Foundation http://www.xiph.org/ * - * * - ******************************************************************** - - function: normalized modified discrete cosine transform - power of two length transform only [64 <= n ] - last mod: $Id: mdct.c 16227 2009-07-08 06:58:46Z xiphmont $ - - Original algorithm adapted long ago from _The use of multirate filter - banks for coding of high quality digital audio_, by T. Sporer, - K. Brandenburg and B. Edler, collection of the European Signal - Processing Conference (EUSIPCO), Amsterdam, June 1992, Vol.1, pp - 211-214 - - The below code implements an algorithm that no longer looks much like - that presented in the paper, but the basic structure remains if you - dig deep enough to see it. - - This module DOES NOT INCLUDE code to generate/apply the window - function. Everybody has their own weird favorite including me... I - happen to like the properties of y=sin(.5PI*sin^2(x)), but others may - vehemently disagree. - - ********************************************************************/ - -/* this can also be run as an integer transform by uncommenting a - define in mdct.h; the integerization is a first pass and although - it's likely stable for Vorbis, the dynamic range is constrained and - roundoff isn't done (so it's noisy). Consider it functional, but - only a starting point. There's no point on a machine with an FPU */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <math.h> -#include "vorbis/codec.h" -#include "mdct.h" -#include "os.h" -#include "misc.h" - -/* build lookups for trig functions; also pre-figure scaling and - some window function algebra. */ - -void mdct_init(mdct_lookup *lookup,int n){ - int *bitrev=_ogg_malloc(sizeof(*bitrev)*(n/4)); - DATA_TYPE *T=_ogg_malloc(sizeof(*T)*(n+n/4)); - - int i; - int n2=n>>1; - int log2n=lookup->log2n=rint(log((float)n)/log(2.f)); - lookup->n=n; - lookup->trig=T; - lookup->bitrev=bitrev; - -/* trig lookups... */ - - for(i=0;i<n/4;i++){ - T[i*2]=FLOAT_CONV(cos((M_PI/n)*(4*i))); - T[i*2+1]=FLOAT_CONV(-sin((M_PI/n)*(4*i))); - T[n2+i*2]=FLOAT_CONV(cos((M_PI/(2*n))*(2*i+1))); - T[n2+i*2+1]=FLOAT_CONV(sin((M_PI/(2*n))*(2*i+1))); - } - for(i=0;i<n/8;i++){ - T[n+i*2]=FLOAT_CONV(cos((M_PI/n)*(4*i+2))*.5); - T[n+i*2+1]=FLOAT_CONV(-sin((M_PI/n)*(4*i+2))*.5); - } - - /* bitreverse lookup... */ - - { - int mask=(1<<(log2n-1))-1,i,j; - int msb=1<<(log2n-2); - for(i=0;i<n/8;i++){ - int acc=0; - for(j=0;msb>>j;j++) - if((msb>>j)&i)acc|=1<<j; - bitrev[i*2]=((~acc)&mask)-1; - bitrev[i*2+1]=acc; - - } - } - lookup->scale=FLOAT_CONV(4.f/n); -} - -/* 8 point butterfly (in place, 4 register) */ -STIN void mdct_butterfly_8(DATA_TYPE *x){ - REG_TYPE r0 = x[6] + x[2]; - REG_TYPE r1 = x[6] - x[2]; - REG_TYPE r2 = x[4] + x[0]; - REG_TYPE r3 = x[4] - x[0]; - - x[6] = r0 + r2; - x[4] = r0 - r2; - - r0 = x[5] - x[1]; - r2 = x[7] - x[3]; - x[0] = r1 + r0; - x[2] = r1 - r0; - - r0 = x[5] + x[1]; - r1 = x[7] + x[3]; - x[3] = r2 + r3; - x[1] = r2 - r3; - x[7] = r1 + r0; - x[5] = r1 - r0; - -} - -/* 16 point butterfly (in place, 4 register) */ -STIN void mdct_butterfly_16(DATA_TYPE *x){ - REG_TYPE r0 = x[1] - x[9]; - REG_TYPE r1 = x[0] - x[8]; - - x[8] += x[0]; - x[9] += x[1]; - x[0] = MULT_NORM((r0 + r1) * cPI2_8); - x[1] = MULT_NORM((r0 - r1) * cPI2_8); - - r0 = x[3] - x[11]; - r1 = x[10] - x[2]; - x[10] += x[2]; - x[11] += x[3]; - x[2] = r0; - x[3] = r1; - - r0 = x[12] - x[4]; - r1 = x[13] - x[5]; - x[12] += x[4]; - x[13] += x[5]; - x[4] = MULT_NORM((r0 - r1) * cPI2_8); - x[5] = MULT_NORM((r0 + r1) * cPI2_8); - - r0 = x[14] - x[6]; - r1 = x[15] - x[7]; - x[14] += x[6]; - x[15] += x[7]; - x[6] = r0; - x[7] = r1; - - mdct_butterfly_8(x); - mdct_butterfly_8(x+8); -} - -/* 32 point butterfly (in place, 4 register) */ -STIN void mdct_butterfly_32(DATA_TYPE *x){ - REG_TYPE r0 = x[30] - x[14]; - REG_TYPE r1 = x[31] - x[15]; - - x[30] += x[14]; - x[31] += x[15]; - x[14] = r0; - x[15] = r1; - - r0 = x[28] - x[12]; - r1 = x[29] - x[13]; - x[28] += x[12]; - x[29] += x[13]; - x[12] = MULT_NORM( r0 * cPI1_8 - r1 * cPI3_8 ); - x[13] = MULT_NORM( r0 * cPI3_8 + r1 * cPI1_8 ); - - r0 = x[26] - x[10]; - r1 = x[27] - x[11]; - x[26] += x[10]; - x[27] += x[11]; - x[10] = MULT_NORM(( r0 - r1 ) * cPI2_8); - x[11] = MULT_NORM(( r0 + r1 ) * cPI2_8); - - r0 = x[24] - x[8]; - r1 = x[25] - x[9]; - x[24] += x[8]; - x[25] += x[9]; - x[8] = MULT_NORM( r0 * cPI3_8 - r1 * cPI1_8 ); - x[9] = MULT_NORM( r1 * cPI3_8 + r0 * cPI1_8 ); - - r0 = x[22] - x[6]; - r1 = x[7] - x[23]; - x[22] += x[6]; - x[23] += x[7]; - x[6] = r1; - x[7] = r0; - - r0 = x[4] - x[20]; - r1 = x[5] - x[21]; - x[20] += x[4]; - x[21] += x[5]; - x[4] = MULT_NORM( r1 * cPI1_8 + r0 * cPI3_8 ); - x[5] = MULT_NORM( r1 * cPI3_8 - r0 * cPI1_8 ); - - r0 = x[2] - x[18]; - r1 = x[3] - x[19]; - x[18] += x[2]; - x[19] += x[3]; - x[2] = MULT_NORM(( r1 + r0 ) * cPI2_8); - x[3] = MULT_NORM(( r1 - r0 ) * cPI2_8); - - r0 = x[0] - x[16]; - r1 = x[1] - x[17]; - x[16] += x[0]; - x[17] += x[1]; - x[0] = MULT_NORM( r1 * cPI3_8 + r0 * cPI1_8 ); - x[1] = MULT_NORM( r1 * cPI1_8 - r0 * cPI3_8 ); - - mdct_butterfly_16(x); - mdct_butterfly_16(x+16); - -} - -/* N point first stage butterfly (in place, 2 register) */ -STIN void mdct_butterfly_first(DATA_TYPE *T, - DATA_TYPE *x, - int points){ - - DATA_TYPE *x1 = x + points - 8; - DATA_TYPE *x2 = x + (points>>1) - 8; - REG_TYPE r0; - REG_TYPE r1; - - do{ - - r0 = x1[6] - x2[6]; - r1 = x1[7] - x2[7]; - x1[6] += x2[6]; - x1[7] += x2[7]; - x2[6] = MULT_NORM(r1 * T[1] + r0 * T[0]); - x2[7] = MULT_NORM(r1 * T[0] - r0 * T[1]); - - r0 = x1[4] - x2[4]; - r1 = x1[5] - x2[5]; - x1[4] += x2[4]; - x1[5] += x2[5]; - x2[4] = MULT_NORM(r1 * T[5] + r0 * T[4]); - x2[5] = MULT_NORM(r1 * T[4] - r0 * T[5]); - - r0 = x1[2] - x2[2]; - r1 = x1[3] - x2[3]; - x1[2] += x2[2]; - x1[3] += x2[3]; - x2[2] = MULT_NORM(r1 * T[9] + r0 * T[8]); - x2[3] = MULT_NORM(r1 * T[8] - r0 * T[9]); - - r0 = x1[0] - x2[0]; - r1 = x1[1] - x2[1]; - x1[0] += x2[0]; - x1[1] += x2[1]; - x2[0] = MULT_NORM(r1 * T[13] + r0 * T[12]); - x2[1] = MULT_NORM(r1 * T[12] - r0 * T[13]); - - x1-=8; - x2-=8; - T+=16; - - }while(x2>=x); -} - -/* N/stage point generic N stage butterfly (in place, 2 register) */ -STIN void mdct_butterfly_generic(DATA_TYPE *T, - DATA_TYPE *x, - int points, - int trigint){ - - DATA_TYPE *x1 = x + points - 8; - DATA_TYPE *x2 = x + (points>>1) - 8; - REG_TYPE r0; - REG_TYPE r1; - - do{ - - r0 = x1[6] - x2[6]; - r1 = x1[7] - x2[7]; - x1[6] += x2[6]; - x1[7] += x2[7]; - x2[6] = MULT_NORM(r1 * T[1] + r0 * T[0]); - x2[7] = MULT_NORM(r1 * T[0] - r0 * T[1]); - - T+=trigint; - - r0 = x1[4] - x2[4]; - r1 = x1[5] - x2[5]; - x1[4] += x2[4]; - x1[5] += x2[5]; - x2[4] = MULT_NORM(r1 * T[1] + r0 * T[0]); - x2[5] = MULT_NORM(r1 * T[0] - r0 * T[1]); - - T+=trigint; - - r0 = x1[2] - x2[2]; - r1 = x1[3] - x2[3]; - x1[2] += x2[2]; - x1[3] += x2[3]; - x2[2] = MULT_NORM(r1 * T[1] + r0 * T[0]); - x2[3] = MULT_NORM(r1 * T[0] - r0 * T[1]); - - T+=trigint; - - r0 = x1[0] - x2[0]; - r1 = x1[1] - x2[1]; - x1[0] += x2[0]; - x1[1] += x2[1]; - x2[0] = MULT_NORM(r1 * T[1] + r0 * T[0]); - x2[1] = MULT_NORM(r1 * T[0] - r0 * T[1]); - - T+=trigint; - x1-=8; - x2-=8; - - }while(x2>=x); -} - -STIN void mdct_butterflies(mdct_lookup *init, - DATA_TYPE *x, - int points){ - - DATA_TYPE *T=init->trig; - int stages=init->log2n-5; - int i,j; - - if(--stages>0){ - mdct_butterfly_first(T,x,points); - } - - for(i=1;--stages>0;i++){ - for(j=0;j<(1<<i);j++) - mdct_butterfly_generic(T,x+(points>>i)*j,points>>i,4<<i); - } - - for(j=0;j<points;j+=32) - mdct_butterfly_32(x+j); - -} - -void mdct_clear(mdct_lookup *l){ - if(l){ - if(l->trig)_ogg_free(l->trig); - if(l->bitrev)_ogg_free(l->bitrev); - memset(l,0,sizeof(*l)); - } -} - -STIN void mdct_bitreverse(mdct_lookup *init, - DATA_TYPE *x){ - int n = init->n; - int *bit = init->bitrev; - DATA_TYPE *w0 = x; - DATA_TYPE *w1 = x = w0+(n>>1); - DATA_TYPE *T = init->trig+n; - - do{ - DATA_TYPE *x0 = x+bit[0]; - DATA_TYPE *x1 = x+bit[1]; - - REG_TYPE r0 = x0[1] - x1[1]; - REG_TYPE r1 = x0[0] + x1[0]; - REG_TYPE r2 = MULT_NORM(r1 * T[0] + r0 * T[1]); - REG_TYPE r3 = MULT_NORM(r1 * T[1] - r0 * T[0]); - - w1 -= 4; - - r0 = HALVE(x0[1] + x1[1]); - r1 = HALVE(x0[0] - x1[0]); - - w0[0] = r0 + r2; - w1[2] = r0 - r2; - w0[1] = r1 + r3; - w1[3] = r3 - r1; - - x0 = x+bit[2]; - x1 = x+bit[3]; - - r0 = x0[1] - x1[1]; - r1 = x0[0] + x1[0]; - r2 = MULT_NORM(r1 * T[2] + r0 * T[3]); - r3 = MULT_NORM(r1 * T[3] - r0 * T[2]); - - r0 = HALVE(x0[1] + x1[1]); - r1 = HALVE(x0[0] - x1[0]); - - w0[2] = r0 + r2; - w1[0] = r0 - r2; - w0[3] = r1 + r3; - w1[1] = r3 - r1; - - T += 4; - bit += 4; - w0 += 4; - - }while(w0<w1); -} - -void mdct_backward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out){ - int n=init->n; - int n2=n>>1; - int n4=n>>2; - - /* rotate */ - - DATA_TYPE *iX = in+n2-7; - DATA_TYPE *oX = out+n2+n4; - DATA_TYPE *T = init->trig+n4; - - do{ - oX -= 4; - oX[0] = MULT_NORM(-iX[2] * T[3] - iX[0] * T[2]); - oX[1] = MULT_NORM (iX[0] * T[3] - iX[2] * T[2]); - oX[2] = MULT_NORM(-iX[6] * T[1] - iX[4] * T[0]); - oX[3] = MULT_NORM (iX[4] * T[1] - iX[6] * T[0]); - iX -= 8; - T += 4; - }while(iX>=in); - - iX = in+n2-8; - oX = out+n2+n4; - T = init->trig+n4; - - do{ - T -= 4; - oX[0] = MULT_NORM (iX[4] * T[3] + iX[6] * T[2]); - oX[1] = MULT_NORM (iX[4] * T[2] - iX[6] * T[3]); - oX[2] = MULT_NORM (iX[0] * T[1] + iX[2] * T[0]); - oX[3] = MULT_NORM (iX[0] * T[0] - iX[2] * T[1]); - iX -= 8; - oX += 4; - }while(iX>=in); - - mdct_butterflies(init,out+n2,n2); - mdct_bitreverse(init,out); - - /* roatate + window */ - - { - DATA_TYPE *oX1=out+n2+n4; - DATA_TYPE *oX2=out+n2+n4; - DATA_TYPE *iX =out; - T =init->trig+n2; - - do{ - oX1-=4; - - oX1[3] = MULT_NORM (iX[0] * T[1] - iX[1] * T[0]); - oX2[0] = -MULT_NORM (iX[0] * T[0] + iX[1] * T[1]); - - oX1[2] = MULT_NORM (iX[2] * T[3] - iX[3] * T[2]); - oX2[1] = -MULT_NORM (iX[2] * T[2] + iX[3] * T[3]); - - oX1[1] = MULT_NORM (iX[4] * T[5] - iX[5] * T[4]); - oX2[2] = -MULT_NORM (iX[4] * T[4] + iX[5] * T[5]); - - oX1[0] = MULT_NORM (iX[6] * T[7] - iX[7] * T[6]); - oX2[3] = -MULT_NORM (iX[6] * T[6] + iX[7] * T[7]); - - oX2+=4; - iX += 8; - T += 8; - }while(iX<oX1); - - iX=out+n2+n4; - oX1=out+n4; - oX2=oX1; - - do{ - oX1-=4; - iX-=4; - - oX2[0] = -(oX1[3] = iX[3]); - oX2[1] = -(oX1[2] = iX[2]); - oX2[2] = -(oX1[1] = iX[1]); - oX2[3] = -(oX1[0] = iX[0]); - - oX2+=4; - }while(oX2<iX); - - iX=out+n2+n4; - oX1=out+n2+n4; - oX2=out+n2; - do{ - oX1-=4; - oX1[0]= iX[3]; - oX1[1]= iX[2]; - oX1[2]= iX[1]; - oX1[3]= iX[0]; - iX+=4; - }while(oX1>oX2); - } -} - -void mdct_forward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out){ - int n=init->n; - int n2=n>>1; - int n4=n>>2; - int n8=n>>3; - DATA_TYPE *w=alloca(n*sizeof(*w)); /* forward needs working space */ - DATA_TYPE *w2=w+n2; - - /* rotate */ - - /* window + rotate + step 1 */ - - REG_TYPE r0; - REG_TYPE r1; - DATA_TYPE *x0=in+n2+n4; - DATA_TYPE *x1=x0+1; - DATA_TYPE *T=init->trig+n2; - - int i=0; - - for(i=0;i<n8;i+=2){ - x0 -=4; - T-=2; - r0= x0[2] + x1[0]; - r1= x0[0] + x1[2]; - w2[i]= MULT_NORM(r1*T[1] + r0*T[0]); - w2[i+1]= MULT_NORM(r1*T[0] - r0*T[1]); - x1 +=4; - } - - x1=in+1; - - for(;i<n2-n8;i+=2){ - T-=2; - x0 -=4; - r0= x0[2] - x1[0]; - r1= x0[0] - x1[2]; - w2[i]= MULT_NORM(r1*T[1] + r0*T[0]); - w2[i+1]= MULT_NORM(r1*T[0] - r0*T[1]); - x1 +=4; - } - - x0=in+n; - - for(;i<n2;i+=2){ - T-=2; - x0 -=4; - r0= -x0[2] - x1[0]; - r1= -x0[0] - x1[2]; - w2[i]= MULT_NORM(r1*T[1] + r0*T[0]); - w2[i+1]= MULT_NORM(r1*T[0] - r0*T[1]); - x1 +=4; - } - - - mdct_butterflies(init,w+n2,n2); - mdct_bitreverse(init,w); - - /* roatate + window */ - - T=init->trig+n2; - x0=out+n2; - - for(i=0;i<n4;i++){ - x0--; - out[i] =MULT_NORM((w[0]*T[0]+w[1]*T[1])*init->scale); - x0[0] =MULT_NORM((w[0]*T[1]-w[1]*T[0])*init->scale); - w+=2; - T+=2; - } -} |