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mss34dsp.c
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1 /*
2  * Common stuff for some Microsoft Screen codecs
3  * Copyright (C) 2012 Konstantin Shishkov
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 #include <stdint.h>
23 #include "libavutil/common.h"
24 #include "mss34dsp.h"
25 
26 static const uint8_t luma_quant[64] = {
27  16, 11, 10, 16, 24, 40, 51, 61,
28  12, 12, 14, 19, 26, 58, 60, 55,
29  14, 13, 16, 24, 40, 57, 69, 56,
30  14, 17, 22, 29, 51, 87, 80, 62,
31  18, 22, 37, 56, 68, 109, 103, 77,
32  24, 35, 55, 64, 81, 104, 113, 92,
33  49, 64, 78, 87, 103, 121, 120, 101,
34  72, 92, 95, 98, 112, 100, 103, 99
35 };
36 
37 static const uint8_t chroma_quant[64] = {
38  17, 18, 24, 47, 99, 99, 99, 99,
39  18, 21, 26, 66, 99, 99, 99, 99,
40  24, 26, 56, 99, 99, 99, 99, 99,
41  47, 66, 99, 99, 99, 99, 99, 99,
42  99, 99, 99, 99, 99, 99, 99, 99,
43  99, 99, 99, 99, 99, 99, 99, 99,
44  99, 99, 99, 99, 99, 99, 99, 99,
45  99, 99, 99, 99, 99, 99, 99, 99
46 };
47 
48 void ff_mss34_gen_quant_mat(uint16_t *qmat, int quality, int luma)
49 {
50  int i;
51  const uint8_t *qsrc = luma ? luma_quant : chroma_quant;
52 
53  if (quality >= 50) {
54  int scale = 200 - 2 * quality;
55 
56  for (i = 0; i < 64; i++)
57  qmat[i] = (qsrc[i] * scale + 50) / 100;
58  } else {
59  for (i = 0; i < 64; i++)
60  qmat[i] = (5000 * qsrc[i] / quality + 50) / 100;
61  }
62 }
63 
64 #define DCT_TEMPLATE(blk, step, SOP, shift) \
65  const int t0 = -39409 * blk[7 * step] - 58980 * blk[1 * step]; \
66  const int t1 = 39410 * blk[1 * step] - 58980 * blk[7 * step]; \
67  const int t2 = -33410 * blk[5 * step] - 167963 * blk[3 * step]; \
68  const int t3 = 33410 * blk[3 * step] - 167963 * blk[5 * step]; \
69  const int t4 = blk[3 * step] + blk[7 * step]; \
70  const int t5 = blk[1 * step] + blk[5 * step]; \
71  const int t6 = 77062 * t4 + 51491 * t5; \
72  const int t7 = 77062 * t5 - 51491 * t4; \
73  const int t8 = 35470 * blk[2 * step] - 85623 * blk[6 * step]; \
74  const int t9 = 35470 * blk[6 * step] + 85623 * blk[2 * step]; \
75  const int tA = SOP(blk[0 * step] - blk[4 * step]); \
76  const int tB = SOP(blk[0 * step] + blk[4 * step]); \
77  \
78  blk[0 * step] = ( t1 + t6 + t9 + tB) >> shift; \
79  blk[1 * step] = ( t3 + t7 + t8 + tA) >> shift; \
80  blk[2 * step] = ( t2 + t6 - t8 + tA) >> shift; \
81  blk[3 * step] = ( t0 + t7 - t9 + tB) >> shift; \
82  blk[4 * step] = (-(t0 + t7) - t9 + tB) >> shift; \
83  blk[5 * step] = (-(t2 + t6) - t8 + tA) >> shift; \
84  blk[6 * step] = (-(t3 + t7) + t8 + tA) >> shift; \
85  blk[7 * step] = (-(t1 + t6) + t9 + tB) >> shift; \
86 
87 #define SOP_ROW(a) (((a) << 16) + 0x2000)
88 #define SOP_COL(a) (((a) + 32) << 16)
89 
90 void ff_mss34_dct_put(uint8_t *dst, ptrdiff_t stride, int *block)
91 {
92  int i, j;
93  int *ptr;
94 
95  ptr = block;
96  for (i = 0; i < 8; i++) {
97  DCT_TEMPLATE(ptr, 1, SOP_ROW, 13);
98  ptr += 8;
99  }
100 
101  ptr = block;
102  for (i = 0; i < 8; i++) {
103  DCT_TEMPLATE(ptr, 8, SOP_COL, 22);
104  ptr++;
105  }
106 
107  ptr = block;
108  for (j = 0; j < 8; j++) {
109  for (i = 0; i < 8; i++)
110  dst[i] = av_clip_uint8(ptr[i] + 128);
111  dst += stride;
112  ptr += 8;
113  }
114 }
void ff_mss34_gen_quant_mat(uint16_t *qmat, int quality, int luma)
Generate quantisation matrix for given quality.
Definition: mss34dsp.c:48
static int16_t block[64]
Definition: dct.c:115
uint8_t
#define SOP_ROW(a)
Definition: mss34dsp.c:87
static const uint8_t luma_quant[64]
Definition: mss34dsp.c:26
void ff_mss34_dct_put(uint8_t *dst, ptrdiff_t stride, int *block)
Transform and output DCT block.
Definition: mss34dsp.c:90
#define SOP_COL(a)
Definition: mss34dsp.c:88
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:105
common internal and external API header
#define stride
static const uint8_t chroma_quant[64]
Definition: mss34dsp.c:37
#define DCT_TEMPLATE(blk, step, SOP, shift)
Definition: mss34dsp.c:64