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
26static 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
37static 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
48void 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
90void ff_mss34_dct_put(uint8_t *dst, int 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}
115