FFmpeg
eaidct.c
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1 /*
2  * Electronic Arts TGQ/TQI/MAD IDCT algorithm
3  * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Electronic Arts TGQ/TQI/MAD IDCT algorithm
25  * @author Peter Ross <pross@xvid.org>
26  */
27 
28 #include "eaidct.h"
29 #include "libavutil/common.h"
30 
31 #define ASQRT 181 /* (1/sqrt(2))<<8 */
32 #define A4 669 /* cos(pi/8)*sqrt(2)<<9 */
33 #define A2 277 /* sin(pi/8)*sqrt(2)<<9 */
34 #define A5 196 /* sin(pi/8)<<9 */
35 
36 #define IDCT_TRANSFORM(dest,s0,s1,s2,s3,s4,s5,s6,s7,d0,d1,d2,d3,d4,d5,d6,d7,munge,src) {\
37  const int a1 = (src)[s1] + (src)[s7]; \
38  const int a7 = (src)[s1] - (src)[s7]; \
39  const int a5 = (src)[s5] + (src)[s3]; \
40  const int a3 = (src)[s5] - (src)[s3]; \
41  const int a2 = (src)[s2] + (src)[s6]; \
42  const int a6 = (ASQRT*((src)[s2] - (src)[s6]))>>8; \
43  const int a0 = (src)[s0] + (src)[s4]; \
44  const int a4 = (src)[s0] - (src)[s4]; \
45  const int b0 = (((A4-A5)*a7 - A5*a3)>>9) + a1+a5; \
46  const int b1 = (((A4-A5)*a7 - A5*a3)>>9) + ((ASQRT*(a1-a5))>>8); \
47  const int b2 = (((A2+A5)*a3 + A5*a7)>>9) + ((ASQRT*(a1-a5))>>8); \
48  const int b3 = ((A2+A5)*a3 + A5*a7)>>9; \
49  (dest)[d0] = munge(a0+a2+a6+b0); \
50  (dest)[d1] = munge(a4+a6 +b1); \
51  (dest)[d2] = munge(a4-a6 +b2); \
52  (dest)[d3] = munge(a0-a2-a6+b3); \
53  (dest)[d4] = munge(a0-a2-a6-b3); \
54  (dest)[d5] = munge(a4-a6 -b2); \
55  (dest)[d6] = munge(a4+a6 -b1); \
56  (dest)[d7] = munge(a0+a2+a6-b0); \
57 }
58 /* end IDCT_TRANSFORM macro */
59 
60 #define MUNGE_NONE(x) (x)
61 #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)
62 
63 #define MUNGE_8BIT(x) av_clip_uint8((x)>>4)
64 #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)
65 
66 static inline void ea_idct_col(int16_t *dest, const int16_t *src) {
67  if ((src[8]|src[16]|src[24]|src[32]|src[40]|src[48]|src[56])==0) {
68  dest[0] =
69  dest[8] =
70  dest[16] =
71  dest[24] =
72  dest[32] =
73  dest[40] =
74  dest[48] =
75  dest[56] = src[0];
76  }else
77  IDCT_COL(dest, src);
78 }
79 
80 void ff_ea_idct_put_c(uint8_t *dest, ptrdiff_t linesize, int16_t *block)
81 {
82  int i;
83  int16_t temp[64];
84  block[0] += 4;
85  for (i=0; i<8; i++)
86  ea_idct_col(&temp[i], &block[i]);
87  for (i=0; i<8; i++)
88  IDCT_ROW( (&dest[i*linesize]), (&temp[8*i]) );
89 }
else temp
Definition: vf_mcdeint.c:256
#define IDCT_COL(dest, src)
Definition: eaidct.c:61
#define src
Definition: vp8dsp.c:254
The exact code depends on how similar the blocks are and how related they are to the block
uint8_t
void ff_ea_idct_put_c(uint8_t *dest, ptrdiff_t linesize, int16_t *block)
Definition: eaidct.c:80
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define IDCT_ROW(dest, src)
Definition: eaidct.c:64
common internal and external API header
static void ea_idct_col(int16_t *dest, const int16_t *src)
Definition: eaidct.c:66