diff options
author | Monty <xiphmont@xiph.org> | 2003-04-19 06:31:30 +0000 |
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committer | Monty <xiphmont@xiph.org> | 2003-04-19 06:31:30 +0000 |
commit | 5a6c26ad884f852dde1c17bb88a83e7e51f07fb2 (patch) | |
tree | 105faeab17c1575af8db63c1198a3ea65536341b | |
parent | 63f97e0602c6bb8aaa22e5706869f282113ec0b9 (diff) | |
download | tremor-5a6c26ad884f852dde1c17bb88a83e7e51f07fb2.tar.gz |
Memory reduction work: completely in-place mdct; requires no
additional working space.
git-svn-id: https://svn.xiph.org/branches/lowmem-branch/Tremor@4618 0101bb08-14d6-0310-b084-bc0e0c8e3800
-rw-r--r-- | mdct.c | 276 |
1 files changed, 101 insertions, 175 deletions
@@ -13,7 +13,7 @@ function: normalized modified discrete cosine transform power of two length transform only [64 <= n ] - last mod: $Id: mdct.c,v 1.9 2002/10/16 09:17:39 xiphmont Exp $ + last mod: $Id: mdct.c,v 1.9.6.1 2003/04/19 06:31:30 xiphmont Exp $ Original algorithm adapted long ago from _The use of multirate filter banks for coding of high quality digital audio_, by T. Sporer, @@ -38,18 +38,17 @@ #include "mdct.h" #include "mdct_lookup.h" - /* 8 point butterfly (in place) */ STIN void mdct_butterfly_8(DATA_TYPE *x){ - REG_TYPE r0 = x[4] + x[0]; - REG_TYPE r1 = x[4] - x[0]; - REG_TYPE r2 = x[5] + x[1]; - REG_TYPE r3 = x[5] - x[1]; - REG_TYPE r4 = x[6] + x[2]; - REG_TYPE r5 = x[6] - x[2]; - REG_TYPE r6 = x[7] + x[3]; - REG_TYPE r7 = x[7] - x[3]; + REG_TYPE r0 = x[0] + x[1]; + REG_TYPE r1 = x[0] - x[1]; + REG_TYPE r2 = x[2] + x[3]; + REG_TYPE r3 = x[2] - x[3]; + REG_TYPE r4 = x[4] + x[5]; + REG_TYPE r5 = x[4] - x[5]; + REG_TYPE r6 = x[6] + x[7]; + REG_TYPE r7 = x[6] - x[7]; x[0] = r5 + r3; x[1] = r7 - r1; @@ -64,29 +63,25 @@ STIN void mdct_butterfly_8(DATA_TYPE *x){ /* 16 point butterfly (in place, 4 register) */ STIN void mdct_butterfly_16(DATA_TYPE *x){ - - REG_TYPE r0, r1; - - r0 = x[ 0] - x[ 8]; x[ 8] += x[ 0]; - r1 = x[ 1] - x[ 9]; x[ 9] += x[ 1]; - x[ 0] = MULT31((r0 + r1) , cPI2_8); - x[ 1] = MULT31((r1 - r0) , cPI2_8); - MB(); - - r0 = x[10] - x[ 2]; x[10] += x[ 2]; - r1 = x[ 3] - x[11]; x[11] += x[ 3]; - x[ 2] = r1; x[ 3] = r0; - MB(); - - r0 = x[12] - x[ 4]; x[12] += x[ 4]; - r1 = x[13] - x[ 5]; x[13] += x[ 5]; - x[ 4] = MULT31((r0 - r1) , cPI2_8); - x[ 5] = MULT31((r0 + r1) , cPI2_8); + + REG_TYPE r0, r1, r2, r3; + + r0 = x[ 8] - x[ 9]; x[ 8] += x[ 9]; + r1 = x[10] - x[11]; x[10] += x[11]; + r2 = x[ 1] - x[ 0]; x[ 9] = x[ 1] + x[0]; + r3 = x[ 3] - x[ 2]; x[11] = x[ 3] + x[2]; + x[ 0] = MULT31((r0 - r1) , cPI2_8); + x[ 1] = MULT31((r2 + r3) , cPI2_8); + x[ 2] = MULT31((r0 + r1) , cPI2_8); + x[ 3] = MULT31((r3 - r2) , cPI2_8); MB(); - r0 = x[14] - x[ 6]; x[14] += x[ 6]; - r1 = x[15] - x[ 7]; x[15] += x[ 7]; - x[ 6] = r0; x[ 7] = r1; + r2 = x[12] - x[13]; x[12] += x[13]; + r3 = x[14] - x[15]; x[14] += x[15]; + r0 = x[ 4] - x[ 5]; x[13] = x[ 5] + x[ 4]; + r1 = x[ 7] - x[ 6]; x[15] = x[ 7] + x[ 6]; + x[ 4] = r2; x[ 5] = r1; + x[ 6] = r3; x[ 7] = r0; MB(); mdct_butterfly_8(x); @@ -96,48 +91,40 @@ STIN void mdct_butterfly_16(DATA_TYPE *x){ /* 32 point butterfly (in place, 4 register) */ STIN void mdct_butterfly_32(DATA_TYPE *x){ - REG_TYPE r0, r1; - - r0 = x[30] - x[14]; x[30] += x[14]; - r1 = x[31] - x[15]; x[31] += x[15]; - x[14] = r0; x[15] = r1; - MB(); - - r0 = x[28] - x[12]; x[28] += x[12]; - r1 = x[29] - x[13]; x[29] += x[13]; - XNPROD31( r0, r1, cPI1_8, cPI3_8, &x[12], &x[13] ); - MB(); - - r0 = x[26] - x[10]; x[26] += x[10]; - r1 = x[27] - x[11]; x[27] += x[11]; - x[10] = MULT31((r0 - r1) , cPI2_8); - x[11] = MULT31((r0 + r1) , cPI2_8); - MB(); - - r0 = x[24] - x[ 8]; x[24] += x[ 8]; - r1 = x[25] - x[ 9]; x[25] += x[ 9]; - XNPROD31( r0, r1, cPI3_8, cPI1_8, &x[ 8], &x[ 9] ); - MB(); + REG_TYPE r0, r1, r2, r3; - r0 = x[22] - x[ 6]; x[22] += x[ 6]; - r1 = x[ 7] - x[23]; x[23] += x[ 7]; - x[ 6] = r1; x[ 7] = r0; + r0 = x[16] - x[17]; x[16] += x[17]; + r1 = x[18] - x[19]; x[18] += x[19]; + r2 = x[ 1] - x[ 0]; x[17] = x[ 1] + x[ 0]; + r3 = x[ 3] - x[ 2]; x[19] = x[ 3] + x[ 2]; + XNPROD31( r0, r1, cPI3_8, cPI1_8, &x[ 0], &x[ 2] ); + XPROD31 ( r2, r3, cPI1_8, cPI3_8, &x[ 1], &x[ 3] ); MB(); - r0 = x[ 4] - x[20]; x[20] += x[ 4]; - r1 = x[ 5] - x[21]; x[21] += x[ 5]; - XPROD31 ( r0, r1, cPI3_8, cPI1_8, &x[ 4], &x[ 5] ); + r0 = x[20] - x[21]; x[20] += x[21]; + r1 = x[22] - x[23]; x[22] += x[23]; + r2 = x[ 5] - x[ 4]; x[21] = x[ 5] + x[ 4]; + r3 = x[ 7] - x[ 6]; x[23] = x[ 7] + x[ 6]; + x[ 4] = MULT31((r0 - r1) , cPI2_8); + x[ 5] = MULT31((r3 + r2) , cPI2_8); + x[ 6] = MULT31((r0 + r1) , cPI2_8); + x[ 7] = MULT31((r3 - r2) , cPI2_8); MB(); - r0 = x[ 2] - x[18]; x[18] += x[ 2]; - r1 = x[ 3] - x[19]; x[19] += x[ 3]; - x[ 2] = MULT31((r1 + r0) , cPI2_8); - x[ 3] = MULT31((r1 - r0) , cPI2_8); + r0 = x[24] - x[25]; x[24] += x[25]; + r1 = x[26] - x[27]; x[26] += x[27]; + r2 = x[ 9] - x[ 8]; x[25] = x[ 9] + x[ 8]; + r3 = x[11] - x[10]; x[27] = x[11] + x[10]; + XNPROD31( r0, r1, cPI1_8, cPI3_8, &x[ 8], &x[10] ); + XPROD31 ( r2, r3, cPI3_8, cPI1_8, &x[ 9], &x[11] ); MB(); - r0 = x[ 0] - x[16]; x[16] += x[ 0]; - r1 = x[ 1] - x[17]; x[17] += x[ 1]; - XPROD31 ( r0, r1, cPI1_8, cPI3_8, &x[ 0], &x[ 1] ); + r0 = x[28] - x[29]; x[28] += x[29]; + r1 = x[30] - x[31]; x[30] += x[31]; + r2 = x[12] - x[13]; x[29] = x[13] + x[12]; + r3 = x[15] - x[14]; x[31] = x[15] + x[14]; + x[12] = r0; x[13] = r3; + x[14] = r1; x[15] = r2; MB(); mdct_butterfly_16(x); @@ -147,87 +134,30 @@ STIN void mdct_butterfly_32(DATA_TYPE *x){ /* N/stage point generic N stage butterfly (in place, 2 register) */ STIN void mdct_butterfly_generic(DATA_TYPE *x,int points,int step){ - LOOKUP_T *T = sincos_lookup0; - DATA_TYPE *x1 = x + points - 8; - DATA_TYPE *x2 = x + (points>>1) - 8; - REG_TYPE r0; - REG_TYPE r1; + LOOKUP_T *T = sincos_lookup0; + DATA_TYPE *x1 = x + points - 4; + DATA_TYPE *x2 = x + (points>>1) - 4; + REG_TYPE r0, r1, r2, r3; do{ - r0 = x1[6] - x2[6]; x1[6] += x2[6]; - r1 = x2[7] - x1[7]; x1[7] += x2[7]; - XPROD31( r1, r0, T[0], T[1], &x2[6], &x2[7] ); T+=step; - - r0 = x1[4] - x2[4]; x1[4] += x2[4]; - r1 = x2[5] - x1[5]; x1[5] += x2[5]; - XPROD31( r1, r0, T[0], T[1], &x2[4], &x2[5] ); T+=step; - - r0 = x1[2] - x2[2]; x1[2] += x2[2]; - r1 = x2[3] - x1[3]; x1[3] += x2[3]; - XPROD31( r1, r0, T[0], T[1], &x2[2], &x2[3] ); T+=step; - - r0 = x1[0] - x2[0]; x1[0] += x2[0]; - r1 = x2[1] - x1[1]; x1[1] += x2[1]; - XPROD31( r1, r0, T[0], T[1], &x2[0], &x2[1] ); T+=step; - - x1-=8; x2-=8; + r0 = x1[0] - x1[1]; x1[0] += x1[1]; + r1 = x1[3] - x1[2]; x1[2] += x1[3]; + r2 = x2[1] - x2[0]; x1[1] = x2[1] + x2[0]; + r3 = x2[3] - x2[2]; x1[3] = x2[3] + x2[2]; + XPROD31( r1, r0, T[0], T[1], &x2[0], &x2[2] ); + XPROD31( r2, r3, T[0], T[1], &x2[1], &x2[3] ); T+=step; + x1-=4; + x2-=4; }while(T<sincos_lookup0+1024); do{ - r0 = x1[6] - x2[6]; x1[6] += x2[6]; - r1 = x1[7] - x2[7]; x1[7] += x2[7]; - XNPROD31( r0, r1, T[0], T[1], &x2[6], &x2[7] ); T-=step; - - r0 = x1[4] - x2[4]; x1[4] += x2[4]; - r1 = x1[5] - x2[5]; x1[5] += x2[5]; - XNPROD31( r0, r1, T[0], T[1], &x2[4], &x2[5] ); T-=step; - - r0 = x1[2] - x2[2]; x1[2] += x2[2]; - r1 = x1[3] - x2[3]; x1[3] += x2[3]; - XNPROD31( r0, r1, T[0], T[1], &x2[2], &x2[3] ); T-=step; - - r0 = x1[0] - x2[0]; x1[0] += x2[0]; - r1 = x1[1] - x2[1]; x1[1] += x2[1]; - XNPROD31( r0, r1, T[0], T[1], &x2[0], &x2[1] ); T-=step; - - x1-=8; x2-=8; - }while(T>sincos_lookup0); - do{ - r0 = x2[6] - x1[6]; x1[6] += x2[6]; - r1 = x2[7] - x1[7]; x1[7] += x2[7]; - XPROD31( r0, r1, T[0], T[1], &x2[6], &x2[7] ); T+=step; - - r0 = x2[4] - x1[4]; x1[4] += x2[4]; - r1 = x2[5] - x1[5]; x1[5] += x2[5]; - XPROD31( r0, r1, T[0], T[1], &x2[4], &x2[5] ); T+=step; - - r0 = x2[2] - x1[2]; x1[2] += x2[2]; - r1 = x2[3] - x1[3]; x1[3] += x2[3]; - XPROD31( r0, r1, T[0], T[1], &x2[2], &x2[3] ); T+=step; - - r0 = x2[0] - x1[0]; x1[0] += x2[0]; - r1 = x2[1] - x1[1]; x1[1] += x2[1]; - XPROD31( r0, r1, T[0], T[1], &x2[0], &x2[1] ); T+=step; - - x1-=8; x2-=8; - }while(T<sincos_lookup0+1024); - do{ - r0 = x1[6] - x2[6]; x1[6] += x2[6]; - r1 = x2[7] - x1[7]; x1[7] += x2[7]; - XNPROD31( r1, r0, T[0], T[1], &x2[6], &x2[7] ); T-=step; - - r0 = x1[4] - x2[4]; x1[4] += x2[4]; - r1 = x2[5] - x1[5]; x1[5] += x2[5]; - XNPROD31( r1, r0, T[0], T[1], &x2[4], &x2[5] ); T-=step; - - r0 = x1[2] - x2[2]; x1[2] += x2[2]; - r1 = x2[3] - x1[3]; x1[3] += x2[3]; - XNPROD31( r1, r0, T[0], T[1], &x2[2], &x2[3] ); T-=step; - - r0 = x1[0] - x2[0]; x1[0] += x2[0]; - r1 = x2[1] - x1[1]; x1[1] += x2[1]; - XNPROD31( r1, r0, T[0], T[1], &x2[0], &x2[1] ); T-=step; - - x1-=8; x2-=8; + r0 = x1[0] - x1[1]; x1[0] += x1[1]; + r1 = x1[2] - x1[3]; x1[2] += x1[3]; + r2 = x2[0] - x2[1]; x1[1] = x2[1] + x2[0]; + r3 = x2[3] - x2[2]; x1[3] = x2[3] + x2[2]; + XNPROD31( r0, r1, T[0], T[1], &x2[0], &x2[2] ); + XNPROD31( r3, r2, T[0], T[1], &x2[1], &x2[3] ); T-=step; + x1-=4; + x2-=4; }while(T>sincos_lookup0); } @@ -235,15 +165,14 @@ STIN void mdct_butterflies(DATA_TYPE *x,int points,int shift){ int stages=8-shift; int i,j; - + for(i=0;--stages>0;i++){ for(j=0;j<(1<<i);j++) mdct_butterfly_generic(x+(points>>i)*j,points>>i,4<<(i+shift)); } - + for(j=0;j<points;j+=32) mdct_butterfly_32(x+j); - } static unsigned char bitrev[16]={0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15}; @@ -346,52 +275,50 @@ void mdct_backward(int n, DATA_TYPE *in, DATA_TYPE *out){ LOOKUP_T *V; int shift; int step; - - for (shift=6;!(n&(1<<shift));shift++); + + for (shift=4;!(n&(1<<shift));shift++); shift=13-shift; step=2<<shift; /* rotate */ - iX = in+n2-7; - oX = out+n2+n4; + iX = in+n2-3; T = sincos_lookup0; do{ - oX-=4; - XPROD31( iX[4], iX[6], T[0], T[1], &oX[2], &oX[3] ); T+=step; - XPROD31( iX[0], iX[2], T[0], T[1], &oX[0], &oX[1] ); T+=step; - iX-=8; + REG_TYPE r0= iX[0]; + REG_TYPE r2= iX[2]; + XPROD31( r0, r2, T[0], T[1], &iX[0], &iX[2] ); T+=step; + iX-=4; }while(iX>=in+n4); do{ - oX-=4; - XPROD31( iX[4], iX[6], T[1], T[0], &oX[2], &oX[3] ); T-=step; - XPROD31( iX[0], iX[2], T[1], T[0], &oX[0], &oX[1] ); T-=step; - iX-=8; + REG_TYPE r0= iX[0]; + REG_TYPE r2= iX[2]; + XPROD31( r0, r2, T[1], T[0], &iX[0], &iX[2] ); T-=step; + iX-=4; }while(iX>=in); - iX = in+n2-8; - oX = out+n2+n4; + iX = in+n2-4; + oX = in; T = sincos_lookup0; - do{ - T+=step; XNPROD31( iX[6], iX[4], T[0], T[1], &oX[0], &oX[1] ); - T+=step; XNPROD31( iX[2], iX[0], T[0], T[1], &oX[2], &oX[3] ); - iX-=8; + REG_TYPE ri0= iX[0]; + REG_TYPE ri2= iX[2]; + REG_TYPE ro0= oX[0]; + REG_TYPE ro2= oX[2]; + + XNPROD31( ro2, ro0, T[1], T[0], &iX[0], &iX[2] ); T+=step; + XNPROD31( ri2, ri0, T[0], T[1], &oX[0], &oX[2] ); + + iX-=4; oX+=4; }while(iX>=in+n4); - do{ - T-=step; XNPROD31( iX[6], iX[4], T[1], T[0], &oX[0], &oX[1] ); - T-=step; XNPROD31( iX[2], iX[0], T[1], T[0], &oX[2], &oX[3] ); - iX-=8; - oX+=4; - }while(iX>=in); - - mdct_butterflies(out+n2,n2,shift); - mdct_bitreverse(out,n,step,shift); + mdct_butterflies(in,n2,shift); + mdct_bitreverse(out,n,step,shift); + /* rotate + window */ - + step>>=2; { DATA_TYPE *oX1=out+n2+n4; @@ -507,4 +434,3 @@ void mdct_backward(int n, DATA_TYPE *in, DATA_TYPE *out){ }while(oX1>oX2); } } - |