mss34dsp.c 4.07 KB
Newer Older
1 2 3 4
/*
 * Common stuff for some Microsoft Screen codecs
 * Copyright (C) 2012 Konstantin Shishkov
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8 9 10 11
 * 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.
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13 14 15 16 17
 * 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
18
 * License along with FFmpeg; if not, write to the Free Software
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <stdint.h>
#include "libavutil/common.h"
#include "mss34dsp.h"

static const uint8_t luma_quant[64] = {
    16,  11,  10,  16,  24,  40,  51,  61,
    12,  12,  14,  19,  26,  58,  60,  55,
    14,  13,  16,  24,  40,  57,  69,  56,
    14,  17,  22,  29,  51,  87,  80,  62,
    18,  22,  37,  56,  68, 109, 103,  77,
    24,  35,  55,  64,  81, 104, 113,  92,
    49,  64,  78,  87, 103, 121, 120, 101,
    72,  92,  95,  98, 112, 100, 103,  99
};

static const uint8_t chroma_quant[64] = {
    17, 18, 24, 47, 99, 99, 99, 99,
    18, 21, 26, 66, 99, 99, 99, 99,
    24, 26, 56, 99, 99, 99, 99, 99,
    47, 66, 99, 99, 99, 99, 99, 99,
    99, 99, 99, 99, 99, 99, 99, 99,
    99, 99, 99, 99, 99, 99, 99, 99,
    99, 99, 99, 99, 99, 99, 99, 99,
    99, 99, 99, 99, 99, 99, 99, 99
};

void ff_mss34_gen_quant_mat(uint16_t *qmat, int quality, int luma)
{
    int i;
    const uint8_t *qsrc = luma ? luma_quant : chroma_quant;

    if (quality >= 50) {
        int scale = 200 - 2 * quality;

        for (i = 0; i < 64; i++)
            qmat[i] = (qsrc[i] * scale + 50) / 100;
    } else {
        for (i = 0; i < 64; i++)
            qmat[i] = (5000 * qsrc[i] / quality + 50) / 100;
    }
}

#define DCT_TEMPLATE(blk, step, SOP, shift)                         \
    const int t0 = -39409 * blk[7 * step] -  58980 * blk[1 * step]; \
    const int t1 =  39410 * blk[1 * step] -  58980 * blk[7 * step]; \
    const int t2 = -33410 * blk[5 * step] - 167963 * blk[3 * step]; \
    const int t3 =  33410 * blk[3 * step] - 167963 * blk[5 * step]; \
    const int t4 =          blk[3 * step] +          blk[7 * step]; \
    const int t5 =          blk[1 * step] +          blk[5 * step]; \
    const int t6 =  77062 * t4            +  51491 * t5;            \
    const int t7 =  77062 * t5            -  51491 * t4;            \
    const int t8 =  35470 * blk[2 * step] -  85623 * blk[6 * step]; \
    const int t9 =  35470 * blk[6 * step] +  85623 * blk[2 * step]; \
    const int tA = SOP(blk[0 * step] - blk[4 * step]);              \
    const int tB = SOP(blk[0 * step] + blk[4 * step]);              \
                                                                    \
    blk[0 * step] = (  t1 + t6  + t9 + tB) >> shift;                \
    blk[1 * step] = (  t3 + t7  + t8 + tA) >> shift;                \
    blk[2 * step] = (  t2 + t6  - t8 + tA) >> shift;                \
    blk[3 * step] = (  t0 + t7  - t9 + tB) >> shift;                \
    blk[4 * step] = (-(t0 + t7) - t9 + tB) >> shift;                \
    blk[5 * step] = (-(t2 + t6) - t8 + tA) >> shift;                \
    blk[6 * step] = (-(t3 + t7) + t8 + tA) >> shift;                \
    blk[7 * step] = (-(t1 + t6) + t9 + tB) >> shift;                \

#define SOP_ROW(a) ((a) << 16) + 0x2000
#define SOP_COL(a) ((a + 32) << 16)

void ff_mss34_dct_put(uint8_t *dst, int stride, int *block)
{
    int i, j;
    int *ptr;

    ptr = block;
    for (i = 0; i < 8; i++) {
        DCT_TEMPLATE(ptr, 1, SOP_ROW, 13);
        ptr += 8;
    }

    ptr = block;
    for (i = 0; i < 8; i++) {
        DCT_TEMPLATE(ptr, 8, SOP_COL, 22);
        ptr++;
    }

    ptr = block;
    for (j = 0; j < 8; j++) {
        for (i = 0; i < 8; i++)
            dst[i] = av_clip_uint8(ptr[i] + 128);
        dst += stride;
        ptr += 8;
    }
}