/***************************************************************************** * * XVID MPEG-4 VIDEO CODEC * - Inverse DCT (More precise version) - * * Copyright (c) 2001 Michael Niedermayer * * Originally distributed under the GNU LGPL License (ffmpeg). * It is licensed under the GNU GPL for the XviD tree. * * This program is free software ; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation ; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY ; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program ; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * $Id: simple_idct.c,v 1.5 2004-04-05 20:36:36 edgomez Exp $ * ****************************************************************************/ /* based upon some outcommented c code from mpeg2dec (idct_mmx.c written by Aaron Holtzman ) */ #include "../portab.h" #include "idct.h" #if 0 #define W1 2841 /* 2048*sqrt (2)*cos (1*pi/16) */ #define W2 2676 /* 2048*sqrt (2)*cos (2*pi/16) */ #define W3 2408 /* 2048*sqrt (2)*cos (3*pi/16) */ #define W4 2048 /* 2048*sqrt (2)*cos (4*pi/16) */ #define W5 1609 /* 2048*sqrt (2)*cos (5*pi/16) */ #define W6 1108 /* 2048*sqrt (2)*cos (6*pi/16) */ #define W7 565 /* 2048*sqrt (2)*cos (7*pi/16) */ #define ROW_SHIFT 8 #define COL_SHIFT 17 #else #define W1 22725 /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */ #define W2 21407 /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */ #define W3 19266 /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */ #define W4 16383 /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */ #define W5 12873 /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */ #define W6 8867 /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */ #define W7 4520 /* cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 */ #define ROW_SHIFT 11 #define COL_SHIFT 20 /* 6 */ #endif /* PPC mac operation. Causes compile problems on newer ppc targets Was originally: #if defined(ARCH_IS_PPC) */ #if 0 /* signed 16x16 -> 32 multiply add accumulate */ #define MAC16(rt, ra, rb) \ asm ("maclhw %0, %2, %3" : "=r" (rt) : "0" (rt), "r" (ra), "r" (rb)); /* signed 16x16 -> 32 multiply */ #define MUL16(rt, ra, rb) \ asm ("mullhw %0, %1, %2" : "=r" (rt) : "r" (ra), "r" (rb)); #else /* signed 16x16 -> 32 multiply add accumulate */ #define MAC16(rt, ra, rb) rt += (ra) * (rb) /* signed 16x16 -> 32 multiply */ #define MUL16(rt, ra, rb) rt = (ra) * (rb) #endif static __inline void idctRowCondDC (int16_t * const row) { int a0, a1, a2, a3, b0, b1, b2, b3; #ifdef FAST_64BIT uint64_t temp; #else uint32_t temp; #endif #ifdef FAST_64BIT #ifdef ARCH_IS_BIG_ENDIAN #define ROW0_MASK 0xffff000000000000LL #else #define ROW0_MASK 0xffffLL #endif if ( ((((uint64_t *)row)[0] & ~ROW0_MASK) | ((uint64_t *)row)[1]) == 0) { temp = (row[0] << 3) & 0xffff; temp += temp << 16; temp += temp << 32; ((uint64_t *)row)[0] = temp; ((uint64_t *)row)[1] = temp; return; } #else if (!(((uint32_t*)row)[1] | ((uint32_t*)row)[2] | ((uint32_t*)row)[3] | row[1])) { temp = (row[0] << 3) & 0xffff; temp += temp << 16; ((uint32_t*)row)[0]=((uint32_t*)row)[1] = ((uint32_t*)row)[2]=((uint32_t*)row)[3] = temp; return; } #endif a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1)); a1 = a0; a2 = a0; a3 = a0; /* no need to optimize : gcc does it */ a0 += W2 * row[2]; a1 += W6 * row[2]; a2 -= W6 * row[2]; a3 -= W2 * row[2]; MUL16(b0, W1, row[1]); MAC16(b0, W3, row[3]); MUL16(b1, W3, row[1]); MAC16(b1, -W7, row[3]); MUL16(b2, W5, row[1]); MAC16(b2, -W1, row[3]); MUL16(b3, W7, row[1]); MAC16(b3, -W5, row[3]); #ifdef FAST_64BIT temp = ((uint64_t*)row)[1]; #else temp = ((uint32_t*)row)[2] | ((uint32_t*)row)[3]; #endif if (temp != 0) { a0 += W4*row[4] + W6*row[6]; a1 += - W4*row[4] - W2*row[6]; a2 += - W4*row[4] + W2*row[6]; a3 += W4*row[4] - W6*row[6]; MAC16(b0, W5, row[5]); MAC16(b0, W7, row[7]); MAC16(b1, -W1, row[5]); MAC16(b1, -W5, row[7]); MAC16(b2, W7, row[5]); MAC16(b2, W3, row[7]); MAC16(b3, W3, row[5]); MAC16(b3, -W1, row[7]); } row[0] = (a0 + b0) >> ROW_SHIFT; row[7] = (a0 - b0) >> ROW_SHIFT; row[1] = (a1 + b1) >> ROW_SHIFT; row[6] = (a1 - b1) >> ROW_SHIFT; row[2] = (a2 + b2) >> ROW_SHIFT; row[5] = (a2 - b2) >> ROW_SHIFT; row[3] = (a3 + b3) >> ROW_SHIFT; row[4] = (a3 - b3) >> ROW_SHIFT; } static __inline void idctSparseCol (int16_t * const col) { int a0, a1, a2, a3, b0, b1, b2, b3; /* XXX: I did that only to give same values as previous code */ a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4)); a1 = a0; a2 = a0; a3 = a0; a0 += + W2*col[8*2]; a1 += + W6*col[8*2]; a2 += - W6*col[8*2]; a3 += - W2*col[8*2]; MUL16(b0, W1, col[8*1]); MUL16(b1, W3, col[8*1]); MUL16(b2, W5, col[8*1]); MUL16(b3, W7, col[8*1]); MAC16(b0, + W3, col[8*3]); MAC16(b1, - W7, col[8*3]); MAC16(b2, - W1, col[8*3]); MAC16(b3, - W5, col[8*3]); if(col[8*4]){ a0 += + W4*col[8*4]; a1 += - W4*col[8*4]; a2 += - W4*col[8*4]; a3 += + W4*col[8*4]; } if (col[8*5]) { MAC16(b0, + W5, col[8*5]); MAC16(b1, - W1, col[8*5]); MAC16(b2, + W7, col[8*5]); MAC16(b3, + W3, col[8*5]); } if(col[8*6]){ a0 += + W6*col[8*6]; a1 += - W2*col[8*6]; a2 += + W2*col[8*6]; a3 += - W6*col[8*6]; } if (col[8*7]) { MAC16(b0, + W7, col[8*7]); MAC16(b1, - W5, col[8*7]); MAC16(b2, + W3, col[8*7]); MAC16(b3, - W1, col[8*7]); } col[0 ] = ((a0 + b0) >> COL_SHIFT); col[8 ] = ((a1 + b1) >> COL_SHIFT); col[16] = ((a2 + b2) >> COL_SHIFT); col[24] = ((a3 + b3) >> COL_SHIFT); col[32] = ((a3 - b3) >> COL_SHIFT); col[40] = ((a2 - b2) >> COL_SHIFT); col[48] = ((a1 - b1) >> COL_SHIFT); col[56] = ((a0 - b0) >> COL_SHIFT); } void simple_idct_c(int16_t * const block) { int i; for(i=0; i<8; i++) idctRowCondDC(block + i*8); for(i=0; i<8; i++) idctSparseCol(block + i); }