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authorDiego 'Flameeyes' Pettenò <flameeyes@gmail.com>2006-12-02 01:19:48 +0000
committerDiego 'Flameeyes' Pettenò <flameeyes@gmail.com>2006-12-02 01:19:48 +0000
commit0ea721f7ce81357bc4ec6eea609cd50482c3d15b (patch)
tree25a0871cb3c06f9716acf9c204192d548f214048 /contrib/ffmpeg/libavcodec/simple_idct.c
parentd8ec380876e7f697ba609546d61757ab3f2d8715 (diff)
downloadxine-lib-0ea721f7ce81357bc4ec6eea609cd50482c3d15b.tar.gz
xine-lib-0ea721f7ce81357bc4ec6eea609cd50482c3d15b.tar.bz2
Start working on a branch where FFmpeg is not copied, patched and carved to be built with automake but instead imported inline and built using its own build system. This is an import of a slightly modified FFmpeg current tree. xine-lib builds, install and run fine with it, but there are of course plenty of things that needs to be fixed before it can even be considered for a 1.2.x series. Work will continue in the next days of course.
CVS patchset: 8397 CVS date: 2006/12/02 01:19:48
Diffstat (limited to 'contrib/ffmpeg/libavcodec/simple_idct.c')
-rw-r--r--contrib/ffmpeg/libavcodec/simple_idct.c587
1 files changed, 587 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/simple_idct.c b/contrib/ffmpeg/libavcodec/simple_idct.c
new file mode 100644
index 000000000..2c026f08f
--- /dev/null
+++ b/contrib/ffmpeg/libavcodec/simple_idct.c
@@ -0,0 +1,587 @@
+/*
+ * Simple IDCT
+ *
+ * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file simple_idct.c
+ * simpleidct in C.
+ */
+
+/*
+ based upon some outcommented c code from mpeg2dec (idct_mmx.c
+ written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>)
+ */
+#include "avcodec.h"
+#include "dsputil.h"
+#include "simple_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
+
+#if defined(ARCH_POWERPC_405)
+
+/* 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 (DCTELEM * 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 WORDS_BIGENDIAN
+#define ROW0_MASK 0xffff000000000000LL
+#else
+#define ROW0_MASK 0xffffLL
+#endif
+ if(sizeof(DCTELEM)==2){
+ 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 (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) {
+ row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3;
+ return;
+ }
+ }
+#else
+ if(sizeof(DCTELEM)==2){
+ 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;
+ }
+ }else{
+ if (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) {
+ row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3;
+ 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 idctSparseColPut (uint8_t *dest, int line_size,
+ DCTELEM * col)
+{
+ int a0, a1, a2, a3, b0, b1, b2, b3;
+ uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+
+ /* 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]);
+ }
+
+ dest[0] = cm[(a0 + b0) >> COL_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(a1 + b1) >> COL_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(a2 + b2) >> COL_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(a3 + b3) >> COL_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(a3 - b3) >> COL_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(a2 - b2) >> COL_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(a1 - b1) >> COL_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(a0 - b0) >> COL_SHIFT];
+}
+
+static inline void idctSparseColAdd (uint8_t *dest, int line_size,
+ DCTELEM * col)
+{
+ int a0, a1, a2, a3, b0, b1, b2, b3;
+ uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+
+ /* 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]);
+ }
+
+ dest[0] = cm[dest[0] + ((a0 + b0) >> COL_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((a1 + b1) >> COL_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((a2 + b2) >> COL_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((a3 + b3) >> COL_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((a3 - b3) >> COL_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((a2 - b2) >> COL_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((a1 - b1) >> COL_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((a0 - b0) >> COL_SHIFT)];
+}
+
+static inline void idctSparseCol (DCTELEM * 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_put(uint8_t *dest, int line_size, DCTELEM *block)
+{
+ int i;
+ for(i=0; i<8; i++)
+ idctRowCondDC(block + i*8);
+
+ for(i=0; i<8; i++)
+ idctSparseColPut(dest + i, line_size, block + i);
+}
+
+void simple_idct_add(uint8_t *dest, int line_size, DCTELEM *block)
+{
+ int i;
+ for(i=0; i<8; i++)
+ idctRowCondDC(block + i*8);
+
+ for(i=0; i<8; i++)
+ idctSparseColAdd(dest + i, line_size, block + i);
+}
+
+void simple_idct(DCTELEM *block)
+{
+ int i;
+ for(i=0; i<8; i++)
+ idctRowCondDC(block + i*8);
+
+ for(i=0; i<8; i++)
+ idctSparseCol(block + i);
+}
+
+/* 2x4x8 idct */
+
+#define CN_SHIFT 12
+#define C_FIX(x) ((int)((x) * (1 << CN_SHIFT) + 0.5))
+#define C1 C_FIX(0.6532814824)
+#define C2 C_FIX(0.2705980501)
+
+/* row idct is multiple by 16 * sqrt(2.0), col idct4 is normalized,
+ and the butterfly must be multiplied by 0.5 * sqrt(2.0) */
+#define C_SHIFT (4+1+12)
+
+static inline void idct4col(uint8_t *dest, int line_size, const DCTELEM *col)
+{
+ int c0, c1, c2, c3, a0, a1, a2, a3;
+ const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+
+ a0 = col[8*0];
+ a1 = col[8*2];
+ a2 = col[8*4];
+ a3 = col[8*6];
+ c0 = ((a0 + a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
+ c2 = ((a0 - a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
+ c1 = a1 * C1 + a3 * C2;
+ c3 = a1 * C2 - a3 * C1;
+ dest[0] = cm[(c0 + c1) >> C_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(c2 + c3) >> C_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(c2 - c3) >> C_SHIFT];
+ dest += line_size;
+ dest[0] = cm[(c0 - c1) >> C_SHIFT];
+}
+
+#define BF(k) \
+{\
+ int a0, a1;\
+ a0 = ptr[k];\
+ a1 = ptr[8 + k];\
+ ptr[k] = a0 + a1;\
+ ptr[8 + k] = a0 - a1;\
+}
+
+/* only used by DV codec. The input must be interlaced. 128 is added
+ to the pixels before clamping to avoid systematic error
+ (1024*sqrt(2)) offset would be needed otherwise. */
+/* XXX: I think a 1.0/sqrt(2) normalization should be needed to
+ compensate the extra butterfly stage - I don't have the full DV
+ specification */
+void simple_idct248_put(uint8_t *dest, int line_size, DCTELEM *block)
+{
+ int i;
+ DCTELEM *ptr;
+
+ /* butterfly */
+ ptr = block;
+ for(i=0;i<4;i++) {
+ BF(0);
+ BF(1);
+ BF(2);
+ BF(3);
+ BF(4);
+ BF(5);
+ BF(6);
+ BF(7);
+ ptr += 2 * 8;
+ }
+
+ /* IDCT8 on each line */
+ for(i=0; i<8; i++) {
+ idctRowCondDC(block + i*8);
+ }
+
+ /* IDCT4 and store */
+ for(i=0;i<8;i++) {
+ idct4col(dest + i, 2 * line_size, block + i);
+ idct4col(dest + line_size + i, 2 * line_size, block + 8 + i);
+ }
+}
+
+/* 8x4 & 4x8 WMV2 IDCT */
+#undef CN_SHIFT
+#undef C_SHIFT
+#undef C_FIX
+#undef C1
+#undef C2
+#define CN_SHIFT 12
+#define C_FIX(x) ((int)((x) * 1.414213562 * (1 << CN_SHIFT) + 0.5))
+#define C1 C_FIX(0.6532814824)
+#define C2 C_FIX(0.2705980501)
+#define C3 C_FIX(0.5)
+#define C_SHIFT (4+1+12)
+static inline void idct4col_add(uint8_t *dest, int line_size, const DCTELEM *col)
+{
+ int c0, c1, c2, c3, a0, a1, a2, a3;
+ const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+
+ a0 = col[8*0];
+ a1 = col[8*1];
+ a2 = col[8*2];
+ a3 = col[8*3];
+ c0 = (a0 + a2)*C3 + (1 << (C_SHIFT - 1));
+ c2 = (a0 - a2)*C3 + (1 << (C_SHIFT - 1));
+ c1 = a1 * C1 + a3 * C2;
+ c3 = a1 * C2 - a3 * C1;
+ dest[0] = cm[dest[0] + ((c0 + c1) >> C_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((c2 + c3) >> C_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((c2 - c3) >> C_SHIFT)];
+ dest += line_size;
+ dest[0] = cm[dest[0] + ((c0 - c1) >> C_SHIFT)];
+}
+
+#define RN_SHIFT 15
+#define R_FIX(x) ((int)((x) * 1.414213562 * (1 << RN_SHIFT) + 0.5))
+#define R1 R_FIX(0.6532814824)
+#define R2 R_FIX(0.2705980501)
+#define R3 R_FIX(0.5)
+#define R_SHIFT 11
+static inline void idct4row(DCTELEM *row)
+{
+ int c0, c1, c2, c3, a0, a1, a2, a3;
+ //const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+
+ a0 = row[0];
+ a1 = row[1];
+ a2 = row[2];
+ a3 = row[3];
+ c0 = (a0 + a2)*R3 + (1 << (R_SHIFT - 1));
+ c2 = (a0 - a2)*R3 + (1 << (R_SHIFT - 1));
+ c1 = a1 * R1 + a3 * R2;
+ c3 = a1 * R2 - a3 * R1;
+ row[0]= (c0 + c1) >> R_SHIFT;
+ row[1]= (c2 + c3) >> R_SHIFT;
+ row[2]= (c2 - c3) >> R_SHIFT;
+ row[3]= (c0 - c1) >> R_SHIFT;
+}
+
+void simple_idct84_add(uint8_t *dest, int line_size, DCTELEM *block)
+{
+ int i;
+
+ /* IDCT8 on each line */
+ for(i=0; i<4; i++) {
+ idctRowCondDC(block + i*8);
+ }
+
+ /* IDCT4 and store */
+ for(i=0;i<8;i++) {
+ idct4col_add(dest + i, line_size, block + i);
+ }
+}
+
+void simple_idct48_add(uint8_t *dest, int line_size, DCTELEM *block)
+{
+ int i;
+
+ /* IDCT4 on each line */
+ for(i=0; i<8; i++) {
+ idct4row(block + i*8);
+ }
+
+ /* IDCT8 and store */
+ for(i=0; i<4; i++){
+ idctSparseColAdd(dest + i, line_size, block + i);
+ }
+}
+