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FFmpeg/libavcodec/simple_idct.c
Arpi 37e8dcda36 new IDCT code by Michael Niedermayer (michaelni@gmx.at) - #define SIMPLE_IDCT to enable
Originally committed as revision 235 to svn://svn.ffmpeg.org/ffmpeg/trunk
2001-12-09 12:39:54 +00:00

232 lines
7.1 KiB
C

/*
Copyright (C) 2001 Michael Niedermayer (michaelni@gmx.at)
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
*/
/*
based upon some outcommented c code from mpeg2dec (idct_mmx.c written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>)
*/
#include <inttypes.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 16384 //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 1
static void inline idctRow (int16_t * row)
{
int a0, a1, a2, a3, b0, b1, b2, b3;
const int C1 =W1;
const int C2 =W2;
const int C3 =W3;
const int C4 =W4;
const int C5 =W5;
const int C6 =W6;
const int C7 =W7;
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;
}
a0 = C4*row[0] + C2*row[2] + C4*row[4] + C6*row[6] + (1<<(ROW_SHIFT-1));
a1 = C4*row[0] + C6*row[2] - C4*row[4] - C2*row[6] + (1<<(ROW_SHIFT-1));
a2 = C4*row[0] - C6*row[2] - C4*row[4] + C2*row[6] + (1<<(ROW_SHIFT-1));
a3 = C4*row[0] - C2*row[2] + C4*row[4] - C6*row[6] + (1<<(ROW_SHIFT-1));
b0 = C1*row[1] + C3*row[3] + C5*row[5] + C7*row[7];
b1 = C3*row[1] - C7*row[3] - C1*row[5] - C5*row[7];
b2 = C5*row[1] - C1*row[3] + C7*row[5] + C3*row[7];
b3 = C7*row[1] - C5*row[3] + C3*row[5] - C1*row[7];
row[0] = (a0 + b0) >> ROW_SHIFT;
row[1] = (a1 + b1) >> ROW_SHIFT;
row[2] = (a2 + b2) >> ROW_SHIFT;
row[3] = (a3 + b3) >> ROW_SHIFT;
row[4] = (a3 - b3) >> ROW_SHIFT;
row[5] = (a2 - b2) >> ROW_SHIFT;
row[6] = (a1 - b1) >> ROW_SHIFT;
row[7] = (a0 - b0) >> ROW_SHIFT;
}
static void inline idctCol (int16_t * col)
{
int a0, a1, a2, a3, b0, b1, b2, b3;
const int C1 =W1;
const int C2 =W2;
const int C3 =W3;
const int C4 =W4;
const int C5 =W5;
const int C6 =W6;
const int C7 =W7;
/*
if( !(col[8*1] | col[8*2] |col[8*3] |col[8*4] |col[8*5] |col[8*6] | col[8*7])) {
col[8*0] = col[8*1] = col[8*2] = col[8*3] = col[8*4] =
col[8*5] = col[8*6] = col[8*7] = col[8*0]<<3;
return;
}*/
col[0] += (1<<(COL_SHIFT-1))/W4;
a0 = C4*col[8*0] + C2*col[8*2] + C4*col[8*4] + C6*col[8*6];
a1 = C4*col[8*0] + C6*col[8*2] - C4*col[8*4] - C2*col[8*6];
a2 = C4*col[8*0] - C6*col[8*2] - C4*col[8*4] + C2*col[8*6];
a3 = C4*col[8*0] - C2*col[8*2] + C4*col[8*4] - C6*col[8*6];
b0 = C1*col[8*1] + C3*col[8*3] + C5*col[8*5] + C7*col[8*7];
b1 = C3*col[8*1] - C7*col[8*3] - C1*col[8*5] - C5*col[8*7];
b2 = C5*col[8*1] - C1*col[8*3] + C7*col[8*5] + C3*col[8*7];
b3 = C7*col[8*1] - C5*col[8*3] + C3*col[8*5] - C1*col[8*7];
col[8*0] = (a0 + b0) >> COL_SHIFT;
col[8*1] = (a1 + b1) >> COL_SHIFT;
col[8*2] = (a2 + b2) >> COL_SHIFT;
col[8*3] = (a3 + b3) >> COL_SHIFT;
col[8*4] = (a3 - b3) >> COL_SHIFT;
col[8*5] = (a2 - b2) >> COL_SHIFT;
col[8*6] = (a1 - b1) >> COL_SHIFT;
col[8*7] = (a0 - b0) >> COL_SHIFT;
}
void simple_idct (short *block)
{
int i;
for(i=0; i<8; i++)
idctRow(block + 8*i);
for(i=0; i<8; i++)
idctCol(block + i);
}
#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 16384 //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 COL_SHIFT 31 // 6
static void inline idctRow (int32_t *out, int16_t * row)
{
int a0, a1, a2, a3, b0, b1, b2, b3;
const int C1 =W1;
const int C2 =W2;
const int C3 =W3;
const int C4 =W4;
const int C5 =W5;
const int C6 =W6;
const int C7 =W7;
/*
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]<<14;
return;
}
*/
a0 = C4*row[0] + C2*row[2] + C4*row[4] + C6*row[6];
a1 = C4*row[0] + C6*row[2] - C4*row[4] - C2*row[6];
a2 = C4*row[0] - C6*row[2] - C4*row[4] + C2*row[6];
a3 = C4*row[0] - C2*row[2] + C4*row[4] - C6*row[6];
b0 = C1*row[1] + C3*row[3] + C5*row[5] + C7*row[7];
b1 = C3*row[1] - C7*row[3] - C1*row[5] - C5*row[7];
b2 = C5*row[1] - C1*row[3] + C7*row[5] + C3*row[7];
b3 = C7*row[1] - C5*row[3] + C3*row[5] - C1*row[7];
out[0] = (a0 + b0);
out[1] = (a1 + b1);
out[2] = (a2 + b2);
out[3] = (a3 + b3);
out[4] = (a3 - b3);
out[5] = (a2 - b2);
out[6] = (a1 - b1);
out[7] = (a0 - b0);
}
static void inline idctCol (int32_t *in, int16_t * col)
{
int64_t a0, a1, a2, a3, b0, b1, b2, b3;
const int64_t C1 =W1;
const int64_t C2 =W2;
const int64_t C3 =W3;
const int64_t C4 =W4;
const int64_t C5 =W5;
const int64_t C6 =W6;
const int64_t C7 =W7;
/*
if( !(col[8*1] | col[8*2] |col[8*3] |col[8*4] |col[8*5] |col[8*6] | col[8*7])) {
col[8*0] = col[8*1] = col[8*2] = col[8*3] = col[8*4] =
col[8*5] = col[8*6] = col[8*7] = col[8*0]<<3;
return;
}*/
in[0] += (1<<(COL_SHIFT-1))/W4;
a0 = C4*in[8*0] + C2*in[8*2] + C4*in[8*4] + C6*in[8*6];
a1 = C4*in[8*0] + C6*in[8*2] - C4*in[8*4] - C2*in[8*6];
a2 = C4*in[8*0] - C6*in[8*2] - C4*in[8*4] + C2*in[8*6];
a3 = C4*in[8*0] - C2*in[8*2] + C4*in[8*4] - C6*in[8*6];
b0 = C1*in[8*1] + C3*in[8*3] + C5*in[8*5] + C7*in[8*7];
b1 = C3*in[8*1] - C7*in[8*3] - C1*in[8*5] - C5*in[8*7];
b2 = C5*in[8*1] - C1*in[8*3] + C7*in[8*5] + C3*in[8*7];
b3 = C7*in[8*1] - C5*in[8*3] + C3*in[8*5] - C1*in[8*7];
col[8*0] = (a0 + b0) >> COL_SHIFT;
col[8*1] = (a1 + b1) >> COL_SHIFT;
col[8*2] = (a2 + b2) >> COL_SHIFT;
col[8*3] = (a3 + b3) >> COL_SHIFT;
col[8*4] = (a3 - b3) >> COL_SHIFT;
col[8*5] = (a2 - b2) >> COL_SHIFT;
col[8*6] = (a1 - b1) >> COL_SHIFT;
col[8*7] = (a0 - b0) >> COL_SHIFT;
}
void simple_idct (short *block)
{
int i;
int32_t temp[64];
for(i=0; i<8; i++)
idctRow(temp+8*i, block + 8*i);
for(i=0; i<8; i++)
idctCol(temp+i, block + i);
}
#endif