90 lines
3.1 KiB
C
90 lines
3.1 KiB
C
/*
|
|
* Electronic Arts TGQ/TQI/MAD IDCT algorithm
|
|
* Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
|
|
*
|
|
* 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
|
|
* Electronic Arts TGQ/TQI/MAD IDCT algorithm
|
|
* @author Peter Ross <pross@xvid.org>
|
|
*/
|
|
|
|
#include "eaidct.h"
|
|
#include "libavutil/common.h"
|
|
|
|
#define ASQRT 181 /* (1/sqrt(2))<<8 */
|
|
#define A4 669 /* cos(pi/8)*sqrt(2)<<9 */
|
|
#define A2 277 /* sin(pi/8)*sqrt(2)<<9 */
|
|
#define A5 196 /* sin(pi/8)<<9 */
|
|
|
|
#define IDCT_TRANSFORM(dest,s0,s1,s2,s3,s4,s5,s6,s7,d0,d1,d2,d3,d4,d5,d6,d7,munge,src) {\
|
|
const int a1 = (src)[s1] + (src)[s7]; \
|
|
const int a7 = (src)[s1] - (src)[s7]; \
|
|
const int a5 = (src)[s5] + (src)[s3]; \
|
|
const int a3 = (src)[s5] - (src)[s3]; \
|
|
const int a2 = (src)[s2] + (src)[s6]; \
|
|
const int a6 = (ASQRT*((src)[s2] - (src)[s6]))>>8; \
|
|
const int a0 = (src)[s0] + (src)[s4]; \
|
|
const int a4 = (src)[s0] - (src)[s4]; \
|
|
const int b0 = (((A4-A5)*a7 - A5*a3)>>9) + a1+a5; \
|
|
const int b1 = (((A4-A5)*a7 - A5*a3)>>9) + ((ASQRT*(a1-a5))>>8); \
|
|
const int b2 = (((A2+A5)*a3 + A5*a7)>>9) + ((ASQRT*(a1-a5))>>8); \
|
|
const int b3 = ((A2+A5)*a3 + A5*a7)>>9; \
|
|
(dest)[d0] = munge(a0+a2+a6+b0); \
|
|
(dest)[d1] = munge(a4+a6 +b1); \
|
|
(dest)[d2] = munge(a4-a6 +b2); \
|
|
(dest)[d3] = munge(a0-a2-a6+b3); \
|
|
(dest)[d4] = munge(a0-a2-a6-b3); \
|
|
(dest)[d5] = munge(a4-a6 -b2); \
|
|
(dest)[d6] = munge(a4+a6 -b1); \
|
|
(dest)[d7] = munge(a0+a2+a6-b0); \
|
|
}
|
|
/* end IDCT_TRANSFORM macro */
|
|
|
|
#define MUNGE_NONE(x) (x)
|
|
#define IDCT_COL(dest,src) IDCT_TRANSFORM(dest,0,8,16,24,32,40,48,56,0,8,16,24,32,40,48,56,MUNGE_NONE,src)
|
|
|
|
#define MUNGE_8BIT(x) av_clip_uint8((x)>>4)
|
|
#define IDCT_ROW(dest,src) IDCT_TRANSFORM(dest,0,1,2,3,4,5,6,7,0,1,2,3,4,5,6,7,MUNGE_8BIT,src)
|
|
|
|
static inline void ea_idct_col(int16_t *dest, const int16_t *src) {
|
|
if ((src[8]|src[16]|src[24]|src[32]|src[40]|src[48]|src[56])==0) {
|
|
dest[0] =
|
|
dest[8] =
|
|
dest[16] =
|
|
dest[24] =
|
|
dest[32] =
|
|
dest[40] =
|
|
dest[48] =
|
|
dest[56] = src[0];
|
|
}else
|
|
IDCT_COL(dest, src);
|
|
}
|
|
|
|
void ff_ea_idct_put_c(uint8_t *dest, ptrdiff_t linesize, int16_t *block)
|
|
{
|
|
int i;
|
|
int16_t temp[64];
|
|
block[0] += 4;
|
|
for (i=0; i<8; i++)
|
|
ea_idct_col(&temp[i], &block[i]);
|
|
for (i=0; i<8; i++)
|
|
IDCT_ROW( (&dest[i*linesize]), (&temp[8*i]) );
|
|
}
|