1
mirror of https://git.videolan.org/git/ffmpeg.git synced 2024-09-06 08:08:58 +02:00
ffmpeg/libavcodec/eaidct.c
Mans Rullgard f3eb008343 eamad/eatgq/eatqi: call special EA IDCT directly
These decoders use a special non-MPEG2 IDCT.  Call it directly
instead of going through dsputil.  There is never any reason
to use a regular IDCT with these decoders or to use the EA IDCT
with other codecs.

This also fixes the bizarre situation of eamad and eatqi decoding
incorrectly if eatgq is disabled.

Signed-off-by: Mans Rullgard <mans@mansr.com>
2012-07-29 21:30:57 +01:00

89 lines
3.0 KiB
C

/*
* Electronic Arts TGQ/TQI/MAD IDCT algorithm
* Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; 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 "dsputil.h"
#include "eaidct.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(DCTELEM *dest, const DCTELEM *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, int linesize, DCTELEM *block) {
int i;
DCTELEM 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]) );
}