/*
 * software YUV to RGB converter
 *
 * Copyright (C) 2009 Konstantin Shishkov
 *
 * 1,4,8bpp support and context / deglobalize stuff
 * by Michael Niedermayer (michaelni@gmx.at)
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <assert.h>

#include "libavutil/cpu.h"
#include "libavutil/bswap.h"
#include "config.h"
#include "rgb2rgb.h"
#include "swscale.h"
#include "swscale_internal.h"
#include "libavutil/pixdesc.h"

extern const uint8_t dither_4x4_16[4][8];
extern const uint8_t dither_8x8_32[8][8];
extern const uint8_t dither_8x8_73[8][8];
extern const uint8_t dither_8x8_220[8][8];

const int32_t ff_yuv2rgb_coeffs[8][4] = {
    { 117504, 138453, 13954, 34903 }, /* no sequence_display_extension */
    { 117504, 138453, 13954, 34903 }, /* ITU-R Rec. 709 (1990) */
    { 104597, 132201, 25675, 53279 }, /* unspecified */
    { 104597, 132201, 25675, 53279 }, /* reserved */
    { 104448, 132798, 24759, 53109 }, /* FCC */
    { 104597, 132201, 25675, 53279 }, /* ITU-R Rec. 624-4 System B, G */
    { 104597, 132201, 25675, 53279 }, /* SMPTE 170M */
    { 117579, 136230, 16907, 35559 }  /* SMPTE 240M (1987) */
};

const int *sws_getCoefficients(int colorspace)
{
    if (colorspace > 7 || colorspace < 0)
        colorspace = SWS_CS_DEFAULT;
    return ff_yuv2rgb_coeffs[colorspace];
}

#define LOADCHROMA(i)                               \
    U = pu[i];                                      \
    V = pv[i];                                      \
    r = (void *)c->table_rV[V+YUVRGB_TABLE_HEADROOM];                     \
    g = (void *)(c->table_gU[U+YUVRGB_TABLE_HEADROOM] + c->table_gV[V+YUVRGB_TABLE_HEADROOM]);  \
    b = (void *)c->table_bU[U+YUVRGB_TABLE_HEADROOM];

#define PUTRGB(dst, src, i)                         \
    Y              = src[2 * i];                    \
    dst[2 * i]     = r[Y] + g[Y] + b[Y];            \
    Y              = src[2 * i + 1];                \
    dst[2 * i + 1] = r[Y] + g[Y] + b[Y];

#define PUTRGB24(dst, src, i)                       \
    Y              = src[2 * i];                    \
    dst[6 * i + 0] = r[Y];                          \
    dst[6 * i + 1] = g[Y];                          \
    dst[6 * i + 2] = b[Y];                          \
    Y              = src[2 * i + 1];                \
    dst[6 * i + 3] = r[Y];                          \
    dst[6 * i + 4] = g[Y];                          \
    dst[6 * i + 5] = b[Y];

#define PUTBGR24(dst, src, i)                       \
    Y              = src[2 * i];                    \
    dst[6 * i + 0] = b[Y];                          \
    dst[6 * i + 1] = g[Y];                          \
    dst[6 * i + 2] = r[Y];                          \
    Y              = src[2 * i + 1];                \
    dst[6 * i + 3] = b[Y];                          \
    dst[6 * i + 4] = g[Y];                          \
    dst[6 * i + 5] = r[Y];

#define PUTRGBA(dst, ysrc, asrc, i, s)                                  \
    Y              = ysrc[2 * i];                                       \
    dst[2 * i]     = r[Y] + g[Y] + b[Y] + (asrc[2 * i]     << s);       \
    Y              = ysrc[2 * i + 1];                                   \
    dst[2 * i + 1] = r[Y] + g[Y] + b[Y] + (asrc[2 * i + 1] << s);

#define PUTRGB48(dst, src, i)                       \
    Y                = src[ 2 * i];                 \
    dst[12 * i +  0] = dst[12 * i +  1] = r[Y];     \
    dst[12 * i +  2] = dst[12 * i +  3] = g[Y];     \
    dst[12 * i +  4] = dst[12 * i +  5] = b[Y];     \
    Y                = src[ 2 * i + 1];             \
    dst[12 * i +  6] = dst[12 * i +  7] = r[Y];     \
    dst[12 * i +  8] = dst[12 * i +  9] = g[Y];     \
    dst[12 * i + 10] = dst[12 * i + 11] = b[Y];

#define PUTBGR48(dst, src, i)                       \
    Y                = src[2 * i];                  \
    dst[12 * i +  0] = dst[12 * i +  1] = b[Y];     \
    dst[12 * i +  2] = dst[12 * i +  3] = g[Y];     \
    dst[12 * i +  4] = dst[12 * i +  5] = r[Y];     \
    Y                = src[2  * i +  1];            \
    dst[12 * i +  6] = dst[12 * i +  7] = b[Y];     \
    dst[12 * i +  8] = dst[12 * i +  9] = g[Y];     \
    dst[12 * i + 10] = dst[12 * i + 11] = r[Y];

#define YUV2RGBFUNC(func_name, dst_type, alpha)                             \
    static int func_name(SwsContext *c, const uint8_t *src[],               \
                         int srcStride[], int srcSliceY, int srcSliceH,     \
                         uint8_t *dst[], int dstStride[])                   \
    {                                                                       \
        int y;                                                              \
                                                                            \
        if (!alpha && c->srcFormat == PIX_FMT_YUV422P) {                    \
            srcStride[1] *= 2;                                              \
            srcStride[2] *= 2;                                              \
        }                                                                   \
        for (y = 0; y < srcSliceH; y += 2) {                                \
            dst_type *dst_1 =                                               \
                (dst_type *)(dst[0] + (y + srcSliceY)     * dstStride[0]);  \
            dst_type *dst_2 =                                               \
                (dst_type *)(dst[0] + (y + srcSliceY + 1) * dstStride[0]);  \
            dst_type av_unused *r, *g, *b;                                  \
            const uint8_t *py_1 = src[0] +  y       * srcStride[0];         \
            const uint8_t *py_2 = py_1   +            srcStride[0];         \
            const uint8_t *pu   = src[1] + (y >> 1) * srcStride[1];         \
            const uint8_t *pv   = src[2] + (y >> 1) * srcStride[2];         \
            const uint8_t av_unused *pa_1, *pa_2;                           \
            unsigned int h_size = c->dstW >> 3;                             \
            if (alpha) {                                                    \
                pa_1 = src[3] + y * srcStride[3];                           \
                pa_2 = pa_1   +     srcStride[3];                           \
            }                                                               \
            while (h_size--) {                                              \
                int av_unused U, V, Y;                                      \

#define ENDYUV2RGBLINE(dst_delta)                   \
    pu    += 4;                                     \
    pv    += 4;                                     \
    py_1  += 8;                                     \
    py_2  += 8;                                     \
    dst_1 += dst_delta;                             \
    dst_2 += dst_delta;                             \
    }                                               \
    if (c->dstW & 4) {                              \
        int av_unused Y, U, V;                      \

#define ENDYUV2RGBFUNC()                            \
            }                                       \
        }                                           \
        return srcSliceH;                           \
    }

#define CLOSEYUV2RGBFUNC(dst_delta)                 \
    ENDYUV2RGBLINE(dst_delta)                       \
    ENDYUV2RGBFUNC()

YUV2RGBFUNC(yuv2rgb_c_48, uint8_t, 0)
    LOADCHROMA(0);
    PUTRGB48(dst_1, py_1, 0);
    PUTRGB48(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTRGB48(dst_2, py_2, 1);
    PUTRGB48(dst_1, py_1, 1);

    LOADCHROMA(2);
    PUTRGB48(dst_1, py_1, 2);
    PUTRGB48(dst_2, py_2, 2);

    LOADCHROMA(3);
    PUTRGB48(dst_2, py_2, 3);
    PUTRGB48(dst_1, py_1, 3);
ENDYUV2RGBLINE(48)
    LOADCHROMA(0);
    PUTRGB48(dst_1, py_1, 0);
    PUTRGB48(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTRGB48(dst_2, py_2, 1);
    PUTRGB48(dst_1, py_1, 1);
ENDYUV2RGBFUNC()

YUV2RGBFUNC(yuv2rgb_c_bgr48, uint8_t, 0)
    LOADCHROMA(0);
    PUTBGR48(dst_1, py_1, 0);
    PUTBGR48(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTBGR48(dst_2, py_2, 1);
    PUTBGR48(dst_1, py_1, 1);

    LOADCHROMA(2);
    PUTBGR48(dst_1, py_1, 2);
    PUTBGR48(dst_2, py_2, 2);

    LOADCHROMA(3);
    PUTBGR48(dst_2, py_2, 3);
    PUTBGR48(dst_1, py_1, 3);
ENDYUV2RGBLINE(48)
    LOADCHROMA(0);
    PUTBGR48(dst_1, py_1, 0);
    PUTBGR48(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTBGR48(dst_2, py_2, 1);
    PUTBGR48(dst_1, py_1, 1);
ENDYUV2RGBFUNC()

YUV2RGBFUNC(yuv2rgb_c_32, uint32_t, 0)
    LOADCHROMA(0);
    PUTRGB(dst_1, py_1, 0);
    PUTRGB(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTRGB(dst_2, py_2, 1);
    PUTRGB(dst_1, py_1, 1);

    LOADCHROMA(2);
    PUTRGB(dst_1, py_1, 2);
    PUTRGB(dst_2, py_2, 2);

    LOADCHROMA(3);
    PUTRGB(dst_2, py_2, 3);
    PUTRGB(dst_1, py_1, 3);
ENDYUV2RGBLINE(8)
    LOADCHROMA(0);
    PUTRGB(dst_1, py_1, 0);
    PUTRGB(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTRGB(dst_2, py_2, 1);
    PUTRGB(dst_1, py_1, 1);
ENDYUV2RGBFUNC()

YUV2RGBFUNC(yuva2rgba_c, uint32_t, 1)
    LOADCHROMA(0);
    PUTRGBA(dst_1, py_1, pa_1, 0, 24);
    PUTRGBA(dst_2, py_2, pa_2, 0, 24);

    LOADCHROMA(1);
    PUTRGBA(dst_2, py_2, pa_1, 1, 24);
    PUTRGBA(dst_1, py_1, pa_2, 1, 24);

    LOADCHROMA(2);
    PUTRGBA(dst_1, py_1, pa_1, 2, 24);
    PUTRGBA(dst_2, py_2, pa_2, 2, 24);

    LOADCHROMA(3);
    PUTRGBA(dst_2, py_2, pa_1, 3, 24);
    PUTRGBA(dst_1, py_1, pa_2, 3, 24);
    pa_1 += 8; \
    pa_2 += 8; \
ENDYUV2RGBLINE(8)
    LOADCHROMA(0);
    PUTRGBA(dst_1, py_1, pa_1, 0, 24);
    PUTRGBA(dst_2, py_2, pa_2, 0, 24);

    LOADCHROMA(1);
    PUTRGBA(dst_2, py_2, pa_1, 1, 24);
    PUTRGBA(dst_1, py_1, pa_2, 1, 24);
ENDYUV2RGBFUNC()

YUV2RGBFUNC(yuva2argb_c, uint32_t, 1)
    LOADCHROMA(0);
    PUTRGBA(dst_1, py_1, pa_1, 0, 0);
    PUTRGBA(dst_2, py_2, pa_2, 0, 0);

    LOADCHROMA(1);
    PUTRGBA(dst_2, py_2, pa_2, 1, 0);
    PUTRGBA(dst_1, py_1, pa_1, 1, 0);

    LOADCHROMA(2);
    PUTRGBA(dst_1, py_1, pa_1, 2, 0);
    PUTRGBA(dst_2, py_2, pa_2, 2, 0);

    LOADCHROMA(3);
    PUTRGBA(dst_2, py_2, pa_2, 3, 0);
    PUTRGBA(dst_1, py_1, pa_1, 3, 0);
    pa_1 += 8; \
    pa_2 += 8; \
ENDYUV2RGBLINE(8)
    LOADCHROMA(0);
    PUTRGBA(dst_1, py_1, pa_1, 0, 0);
    PUTRGBA(dst_2, py_2, pa_2, 0, 0);

    LOADCHROMA(1);
    PUTRGBA(dst_2, py_2, pa_2, 1, 0);
    PUTRGBA(dst_1, py_1, pa_1, 1, 0);
ENDYUV2RGBFUNC()

YUV2RGBFUNC(yuv2rgb_c_24_rgb, uint8_t, 0)
    LOADCHROMA(0);
    PUTRGB24(dst_1, py_1, 0);
    PUTRGB24(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTRGB24(dst_2, py_2, 1);
    PUTRGB24(dst_1, py_1, 1);

    LOADCHROMA(2);
    PUTRGB24(dst_1, py_1, 2);
    PUTRGB24(dst_2, py_2, 2);

    LOADCHROMA(3);
    PUTRGB24(dst_2, py_2, 3);
    PUTRGB24(dst_1, py_1, 3);
ENDYUV2RGBLINE(24)
    LOADCHROMA(0);
    PUTRGB24(dst_1, py_1, 0);
    PUTRGB24(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTRGB24(dst_2, py_2, 1);
    PUTRGB24(dst_1, py_1, 1);
ENDYUV2RGBFUNC()

// only trivial mods from yuv2rgb_c_24_rgb
YUV2RGBFUNC(yuv2rgb_c_24_bgr, uint8_t, 0)
    LOADCHROMA(0);
    PUTBGR24(dst_1, py_1, 0);
    PUTBGR24(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTBGR24(dst_2, py_2, 1);
    PUTBGR24(dst_1, py_1, 1);

    LOADCHROMA(2);
    PUTBGR24(dst_1, py_1, 2);
    PUTBGR24(dst_2, py_2, 2);

    LOADCHROMA(3);
    PUTBGR24(dst_2, py_2, 3);
    PUTBGR24(dst_1, py_1, 3);
ENDYUV2RGBLINE(24)
    LOADCHROMA(0);
    PUTBGR24(dst_1, py_1, 0);
    PUTBGR24(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTBGR24(dst_2, py_2, 1);
    PUTBGR24(dst_1, py_1, 1);
ENDYUV2RGBFUNC()

// This is exactly the same code as yuv2rgb_c_32 except for the types of
// r, g, b, dst_1, dst_2
YUV2RGBFUNC(yuv2rgb_c_16, uint16_t, 0)
    LOADCHROMA(0);
    PUTRGB(dst_1, py_1, 0);
    PUTRGB(dst_2, py_2, 0);

    LOADCHROMA(1);
    PUTRGB(dst_2, py_2, 1);
    PUTRGB(dst_1, py_1, 1);

    LOADCHROMA(2);
    PUTRGB(dst_1, py_1, 2);
    PUTRGB(dst_2, py_2, 2);

    LOADCHROMA(3);
    PUTRGB(dst_2, py_2, 3);
    PUTRGB(dst_1, py_1, 3);
CLOSEYUV2RGBFUNC(8)

// r, g, b, dst_1, dst_2
YUV2RGBFUNC(yuv2rgb_c_12_ordered_dither, uint16_t, 0)
    const uint8_t *d16 = dither_4x4_16[y & 3];

#define PUTRGB12(dst, src, i, o)                    \
    Y              = src[2 * i];                    \
    dst[2 * i]     = r[Y + d16[0 + o]] +            \
                     g[Y + d16[0 + o]] +            \
                     b[Y + d16[0 + o]];             \
    Y              = src[2 * i + 1];                \
    dst[2 * i + 1] = r[Y + d16[1 + o]] +            \
                     g[Y + d16[1 + o]] +            \
                     b[Y + d16[1 + o]];

    LOADCHROMA(0);
    PUTRGB12(dst_1, py_1, 0, 0);
    PUTRGB12(dst_2, py_2, 0, 0 + 8);

    LOADCHROMA(1);
    PUTRGB12(dst_2, py_2, 1, 2 + 8);
    PUTRGB12(dst_1, py_1, 1, 2);

    LOADCHROMA(2);
    PUTRGB12(dst_1, py_1, 2, 4);
    PUTRGB12(dst_2, py_2, 2, 4 + 8);

    LOADCHROMA(3);
    PUTRGB12(dst_2, py_2, 3, 6 + 8);
    PUTRGB12(dst_1, py_1, 3, 6);
CLOSEYUV2RGBFUNC(8)

// r, g, b, dst_1, dst_2
YUV2RGBFUNC(yuv2rgb_c_8_ordered_dither, uint8_t, 0)
    const uint8_t *d32 = dither_8x8_32[y & 7];
    const uint8_t *d64 = dither_8x8_73[y & 7];

#define PUTRGB8(dst, src, i, o)                     \
    Y              = src[2 * i];                    \
    dst[2 * i]     = r[Y + d32[0 + o]] +            \
                     g[Y + d32[0 + o]] +            \
                     b[Y + d64[0 + o]];             \
    Y              = src[2 * i + 1];                \
    dst[2 * i + 1] = r[Y + d32[1 + o]] +            \
                     g[Y + d32[1 + o]] +            \
                     b[Y + d64[1 + o]];

    LOADCHROMA(0);
    PUTRGB8(dst_1, py_1, 0, 0);
    PUTRGB8(dst_2, py_2, 0, 0 + 8);

    LOADCHROMA(1);
    PUTRGB8(dst_2, py_2, 1, 2 + 8);
    PUTRGB8(dst_1, py_1, 1, 2);

    LOADCHROMA(2);
    PUTRGB8(dst_1, py_1, 2, 4);
    PUTRGB8(dst_2, py_2, 2, 4 + 8);

    LOADCHROMA(3);
    PUTRGB8(dst_2, py_2, 3, 6 + 8);
    PUTRGB8(dst_1, py_1, 3, 6);
CLOSEYUV2RGBFUNC(8)

YUV2RGBFUNC(yuv2rgb_c_4_ordered_dither, uint8_t, 0)
    const uint8_t * d64 = dither_8x8_73[y & 7];
    const uint8_t *d128 = dither_8x8_220[y & 7];
    int acc;

#define PUTRGB4D(dst, src, i, o)                    \
    Y      = src[2 * i];                            \
    acc    = r[Y + d128[0 + o]] +                   \
             g[Y +  d64[0 + o]] +                   \
             b[Y + d128[0 + o]];                    \
    Y      = src[2 * i + 1];                        \
    acc   |= (r[Y + d128[1 + o]] +                  \
              g[Y +  d64[1 + o]] +                  \
              b[Y + d128[1 + o]]) << 4;             \
    dst[i] = acc;

    LOADCHROMA(0);
    PUTRGB4D(dst_1, py_1, 0, 0);
    PUTRGB4D(dst_2, py_2, 0, 0 + 8);

    LOADCHROMA(1);
    PUTRGB4D(dst_2, py_2, 1, 2 + 8);
    PUTRGB4D(dst_1, py_1, 1, 2);

    LOADCHROMA(2);
    PUTRGB4D(dst_1, py_1, 2, 4);
    PUTRGB4D(dst_2, py_2, 2, 4 + 8);

    LOADCHROMA(3);
    PUTRGB4D(dst_2, py_2, 3, 6 + 8);
    PUTRGB4D(dst_1, py_1, 3, 6);
CLOSEYUV2RGBFUNC(4)

YUV2RGBFUNC(yuv2rgb_c_4b_ordered_dither, uint8_t, 0)
    const uint8_t *d64  = dither_8x8_73[y & 7];
    const uint8_t *d128 = dither_8x8_220[y & 7];

#define PUTRGB4DB(dst, src, i, o)                   \
    Y              = src[2 * i];                    \
    dst[2 * i]     = r[Y + d128[0 + o]] +           \
                     g[Y +  d64[0 + o]] +           \
                     b[Y + d128[0 + o]];            \
    Y              = src[2 * i + 1];                \
    dst[2 * i + 1] = r[Y + d128[1 + o]] +           \
                     g[Y +  d64[1 + o]] +           \
                     b[Y + d128[1 + o]];

    LOADCHROMA(0);
    PUTRGB4DB(dst_1, py_1, 0, 0);
    PUTRGB4DB(dst_2, py_2, 0, 0 + 8);

    LOADCHROMA(1);
    PUTRGB4DB(dst_2, py_2, 1, 2 + 8);
    PUTRGB4DB(dst_1, py_1, 1, 2);

    LOADCHROMA(2);
    PUTRGB4DB(dst_1, py_1, 2, 4);
    PUTRGB4DB(dst_2, py_2, 2, 4 + 8);

    LOADCHROMA(3);
    PUTRGB4DB(dst_2, py_2, 3, 6 + 8);
    PUTRGB4DB(dst_1, py_1, 3, 6);
CLOSEYUV2RGBFUNC(8)

YUV2RGBFUNC(yuv2rgb_c_1_ordered_dither, uint8_t, 0)
    const uint8_t *d128 = dither_8x8_220[y & 7];
    char out_1 = 0, out_2 = 0;
    g = c->table_gU[128 + YUVRGB_TABLE_HEADROOM] + c->table_gV[128 + YUVRGB_TABLE_HEADROOM];

#define PUTRGB1(out, src, i, o)                     \
    Y    = src[2 * i];                              \
    out += out + g[Y + d128[0 + o]];                \
    Y    = src[2 * i + 1];                          \
    out += out + g[Y + d128[1 + o]];

    PUTRGB1(out_1, py_1, 0, 0);
    PUTRGB1(out_2, py_2, 0, 0 + 8);

    PUTRGB1(out_2, py_2, 1, 2 + 8);
    PUTRGB1(out_1, py_1, 1, 2);

    PUTRGB1(out_1, py_1, 2, 4);
    PUTRGB1(out_2, py_2, 2, 4 + 8);

    PUTRGB1(out_2, py_2, 3, 6 + 8);
    PUTRGB1(out_1, py_1, 3, 6);

    dst_1[0] = out_1;
    dst_2[0] = out_2;
CLOSEYUV2RGBFUNC(1)

SwsFunc ff_yuv2rgb_get_func_ptr(SwsContext *c)
{
    SwsFunc t = NULL;

    if (HAVE_MMX)
        t = ff_yuv2rgb_init_mmx(c);
    else if (HAVE_VIS)
        t = ff_yuv2rgb_init_vis(c);
    else if (HAVE_ALTIVEC)
        t = ff_yuv2rgb_init_altivec(c);
    else if (ARCH_BFIN)
        t = ff_yuv2rgb_get_func_ptr_bfin(c);

    if (t)
        return t;

    av_log(c, AV_LOG_WARNING,
           "No accelerated colorspace conversion found from %s to %s.\n",
           av_get_pix_fmt_name(c->srcFormat), av_get_pix_fmt_name(c->dstFormat));

    switch (c->dstFormat) {
    case PIX_FMT_BGR48BE:
    case PIX_FMT_BGR48LE:
        return yuv2rgb_c_bgr48;
    case PIX_FMT_RGB48BE:
    case PIX_FMT_RGB48LE:
        return yuv2rgb_c_48;
    case PIX_FMT_ARGB:
    case PIX_FMT_ABGR:
        if (CONFIG_SWSCALE_ALPHA && isALPHA(c->srcFormat))
            return yuva2argb_c;
    case PIX_FMT_RGBA:
    case PIX_FMT_BGRA:
        return (CONFIG_SWSCALE_ALPHA && isALPHA(c->srcFormat)) ? yuva2rgba_c : yuv2rgb_c_32;
    case PIX_FMT_RGB24:
        return yuv2rgb_c_24_rgb;
    case PIX_FMT_BGR24:
        return yuv2rgb_c_24_bgr;
    case PIX_FMT_RGB565:
    case PIX_FMT_BGR565:
    case PIX_FMT_RGB555:
    case PIX_FMT_BGR555:
        return yuv2rgb_c_16;
    case PIX_FMT_RGB444:
    case PIX_FMT_BGR444:
        return yuv2rgb_c_12_ordered_dither;
    case PIX_FMT_RGB8:
    case PIX_FMT_BGR8:
        return yuv2rgb_c_8_ordered_dither;
    case PIX_FMT_RGB4:
    case PIX_FMT_BGR4:
        return yuv2rgb_c_4_ordered_dither;
    case PIX_FMT_RGB4_BYTE:
    case PIX_FMT_BGR4_BYTE:
        return yuv2rgb_c_4b_ordered_dither;
    case PIX_FMT_MONOBLACK:
        return yuv2rgb_c_1_ordered_dither;
    default:
        assert(0);
    }
    return NULL;
}

static void fill_table(uint8_t* table[256 + 2*YUVRGB_TABLE_HEADROOM], const int elemsize,
                       const int inc, void *y_tab)
{
    int i;
    uint8_t *y_table = y_tab;

    y_table -= elemsize * (inc >> 9);

    for (i = 0; i < 256 + 2*YUVRGB_TABLE_HEADROOM; i++) {
        int64_t cb = av_clip(i-YUVRGB_TABLE_HEADROOM, 0, 255)*inc;
        table[i] = y_table + elemsize * (cb >> 16);
    }
}

static void fill_gv_table(int table[256 + 2*YUVRGB_TABLE_HEADROOM], const int elemsize, const int inc)
{
    int i;
    int off    = -(inc >> 9);

    for (i = 0; i < 256 + 2*YUVRGB_TABLE_HEADROOM; i++) {
        int64_t cb = av_clip(i-YUVRGB_TABLE_HEADROOM, 0, 255)*inc;
        table[i] = elemsize * (off + (cb >> 16));
    }
}

static uint16_t roundToInt16(int64_t f)
{
    int r = (f + (1 << 15)) >> 16;

    if (r < -0x7FFF)
        return 0x8000;
    else if (r > 0x7FFF)
        return 0x7FFF;
    else
        return r;
}

av_cold int ff_yuv2rgb_c_init_tables(SwsContext *c, const int inv_table[4],
                                     int fullRange, int brightness,
                                     int contrast, int saturation)
{
    const int isRgb = c->dstFormat == PIX_FMT_RGB32     ||
                      c->dstFormat == PIX_FMT_RGB32_1   ||
                      c->dstFormat == PIX_FMT_BGR24     ||
                      c->dstFormat == PIX_FMT_RGB565BE  ||
                      c->dstFormat == PIX_FMT_RGB565LE  ||
                      c->dstFormat == PIX_FMT_RGB555BE  ||
                      c->dstFormat == PIX_FMT_RGB555LE  ||
                      c->dstFormat == PIX_FMT_RGB444BE  ||
                      c->dstFormat == PIX_FMT_RGB444LE  ||
                      c->dstFormat == PIX_FMT_RGB8      ||
                      c->dstFormat == PIX_FMT_RGB4      ||
                      c->dstFormat == PIX_FMT_RGB4_BYTE ||
                      c->dstFormat == PIX_FMT_MONOBLACK;
    const int isNotNe = c->dstFormat == PIX_FMT_NE(RGB565LE, RGB565BE) ||
                        c->dstFormat == PIX_FMT_NE(RGB555LE, RGB555BE) ||
                        c->dstFormat == PIX_FMT_NE(RGB444LE, RGB444BE) ||
                        c->dstFormat == PIX_FMT_NE(BGR565LE, BGR565BE) ||
                        c->dstFormat == PIX_FMT_NE(BGR555LE, BGR555BE) ||
                        c->dstFormat == PIX_FMT_NE(BGR444LE, BGR444BE);
    const int bpp = c->dstFormatBpp;
    uint8_t *y_table;
    uint16_t *y_table16;
    uint32_t *y_table32;
    int i, base, rbase, gbase, bbase, av_uninit(abase), needAlpha;
    const int yoffs = fullRange ? 384 : 326;

    int64_t crv =  inv_table[0];
    int64_t cbu =  inv_table[1];
    int64_t cgu = -inv_table[2];
    int64_t cgv = -inv_table[3];
    int64_t cy  = 1 << 16;
    int64_t oy  = 0;
    int64_t yb  = 0;

    if (!fullRange) {
        cy = (cy * 255) / 219;
        oy = 16 << 16;
    } else {
        crv = (crv * 224) / 255;
        cbu = (cbu * 224) / 255;
        cgu = (cgu * 224) / 255;
        cgv = (cgv * 224) / 255;
    }

    cy   = (cy  * contrast)              >> 16;
    crv  = (crv * contrast * saturation) >> 32;
    cbu  = (cbu * contrast * saturation) >> 32;
    cgu  = (cgu * contrast * saturation) >> 32;
    cgv  = (cgv * contrast * saturation) >> 32;
    oy  -= 256 * brightness;

    c->uOffset = 0x0400040004000400LL;
    c->vOffset = 0x0400040004000400LL;
    c->yCoeff  = roundToInt16(cy  * 8192) * 0x0001000100010001ULL;
    c->vrCoeff = roundToInt16(crv * 8192) * 0x0001000100010001ULL;
    c->ubCoeff = roundToInt16(cbu * 8192) * 0x0001000100010001ULL;
    c->vgCoeff = roundToInt16(cgv * 8192) * 0x0001000100010001ULL;
    c->ugCoeff = roundToInt16(cgu * 8192) * 0x0001000100010001ULL;
    c->yOffset = roundToInt16(oy  *    8) * 0x0001000100010001ULL;

    c->yuv2rgb_y_coeff   = (int16_t)roundToInt16(cy  << 13);
    c->yuv2rgb_y_offset  = (int16_t)roundToInt16(oy  <<  9);
    c->yuv2rgb_v2r_coeff = (int16_t)roundToInt16(crv << 13);
    c->yuv2rgb_v2g_coeff = (int16_t)roundToInt16(cgv << 13);
    c->yuv2rgb_u2g_coeff = (int16_t)roundToInt16(cgu << 13);
    c->yuv2rgb_u2b_coeff = (int16_t)roundToInt16(cbu << 13);

    //scale coefficients by cy
    crv = ((crv << 16) + 0x8000) / cy;
    cbu = ((cbu << 16) + 0x8000) / cy;
    cgu = ((cgu << 16) + 0x8000) / cy;
    cgv = ((cgv << 16) + 0x8000) / cy;

    av_free(c->yuvTable);

    switch (bpp) {
    case 1:
        c->yuvTable = av_malloc(1024);
        y_table     = c->yuvTable;
        yb = -(384 << 16) - oy;
        for (i = 0; i < 1024 - 110; i++) {
            y_table[i + 110]  = av_clip_uint8((yb + 0x8000) >> 16) >> 7;
            yb               += cy;
        }
        fill_table(c->table_gU, 1, cgu, y_table + yoffs);
        fill_gv_table(c->table_gV, 1, cgv);
        break;
    case 4:
    case 4 | 128:
        rbase       = isRgb ? 3 : 0;
        gbase       = 1;
        bbase       = isRgb ? 0 : 3;
        c->yuvTable = av_malloc(1024 * 3);
        y_table     = c->yuvTable;
        yb = -(384 << 16) - oy;
        for (i = 0; i < 1024 - 110; i++) {
            int yval                = av_clip_uint8((yb + 0x8000) >> 16);
            y_table[i + 110]        = (yval >> 7)        << rbase;
            y_table[i +  37 + 1024] = ((yval + 43) / 85) << gbase;
            y_table[i + 110 + 2048] = (yval >> 7)        << bbase;
            yb += cy;
        }
        fill_table(c->table_rV, 1, crv, y_table + yoffs);
        fill_table(c->table_gU, 1, cgu, y_table + yoffs + 1024);
        fill_table(c->table_bU, 1, cbu, y_table + yoffs + 2048);
        fill_gv_table(c->table_gV, 1, cgv);
        break;
    case 8:
        rbase       = isRgb ? 5 : 0;
        gbase       = isRgb ? 2 : 3;
        bbase       = isRgb ? 0 : 6;
        c->yuvTable = av_malloc(1024 * 3);
        y_table     = c->yuvTable;
        yb = -(384 << 16) - oy;
        for (i = 0; i < 1024 - 38; i++) {
            int yval               = av_clip_uint8((yb + 0x8000) >> 16);
            y_table[i + 16]        = ((yval + 18) / 36) << rbase;
            y_table[i + 16 + 1024] = ((yval + 18) / 36) << gbase;
            y_table[i + 37 + 2048] = ((yval + 43) / 85) << bbase;
            yb += cy;
        }
        fill_table(c->table_rV, 1, crv, y_table + yoffs);
        fill_table(c->table_gU, 1, cgu, y_table + yoffs + 1024);
        fill_table(c->table_bU, 1, cbu, y_table + yoffs + 2048);
        fill_gv_table(c->table_gV, 1, cgv);
        break;
    case 12:
        rbase       = isRgb ? 8 : 0;
        gbase       = 4;
        bbase       = isRgb ? 0 : 8;
        c->yuvTable = av_malloc(1024 * 3 * 2);
        y_table16   = c->yuvTable;
        yb = -(384 << 16) - oy;
        for (i = 0; i < 1024; i++) {
            uint8_t yval        = av_clip_uint8((yb + 0x8000) >> 16);
            y_table16[i]        = (yval >> 4) << rbase;
            y_table16[i + 1024] = (yval >> 4) << gbase;
            y_table16[i + 2048] = (yval >> 4) << bbase;
            yb += cy;
        }
        if (isNotNe)
            for (i = 0; i < 1024 * 3; i++)
                y_table16[i] = av_bswap16(y_table16[i]);
        fill_table(c->table_rV, 2, crv, y_table16 + yoffs);
        fill_table(c->table_gU, 2, cgu, y_table16 + yoffs + 1024);
        fill_table(c->table_bU, 2, cbu, y_table16 + yoffs + 2048);
        fill_gv_table(c->table_gV, 2, cgv);
        break;
    case 15:
    case 16:
        rbase       = isRgb ? bpp - 5 : 0;
        gbase       = 5;
        bbase       = isRgb ? 0 : (bpp - 5);
        c->yuvTable = av_malloc(1024 * 3 * 2);
        y_table16   = c->yuvTable;
        yb = -(384 << 16) - oy;
        for (i = 0; i < 1024; i++) {
            uint8_t yval        = av_clip_uint8((yb + 0x8000) >> 16);
            y_table16[i]        = (yval >> 3)          << rbase;
            y_table16[i + 1024] = (yval >> (18 - bpp)) << gbase;
            y_table16[i + 2048] = (yval >> 3)          << bbase;
            yb += cy;
        }
        if (isNotNe)
            for (i = 0; i < 1024 * 3; i++)
                y_table16[i] = av_bswap16(y_table16[i]);
        fill_table(c->table_rV, 2, crv, y_table16 + yoffs);
        fill_table(c->table_gU, 2, cgu, y_table16 + yoffs + 1024);
        fill_table(c->table_bU, 2, cbu, y_table16 + yoffs + 2048);
        fill_gv_table(c->table_gV, 2, cgv);
        break;
    case 24:
    case 48:
        c->yuvTable = av_malloc(1024);
        y_table     = c->yuvTable;
        yb = -(384 << 16) - oy;
        for (i = 0; i < 1024; i++) {
            y_table[i]  = av_clip_uint8((yb + 0x8000) >> 16);
            yb         += cy;
        }
        fill_table(c->table_rV, 1, crv, y_table + yoffs);
        fill_table(c->table_gU, 1, cgu, y_table + yoffs);
        fill_table(c->table_bU, 1, cbu, y_table + yoffs);
        fill_gv_table(c->table_gV, 1, cgv);
        break;
    case 32:
        base      = (c->dstFormat == PIX_FMT_RGB32_1 ||
                     c->dstFormat == PIX_FMT_BGR32_1) ? 8 : 0;
        rbase     = base + (isRgb ? 16 : 0);
        gbase     = base + 8;
        bbase     = base + (isRgb ? 0 : 16);
        needAlpha = CONFIG_SWSCALE_ALPHA && isALPHA(c->srcFormat);
        if (!needAlpha)
            abase = (base + 24) & 31;
        c->yuvTable = av_malloc(1024 * 3 * 4);
        y_table32   = c->yuvTable;
        yb = -(384 << 16) - oy;
        for (i = 0; i < 1024; i++) {
            unsigned yval       = av_clip_uint8((yb + 0x8000) >> 16);
            y_table32[i]        = (yval << rbase) +
                                  (needAlpha ? 0 : (255u << abase));
            y_table32[i + 1024] =  yval << gbase;
            y_table32[i + 2048] =  yval << bbase;
            yb += cy;
        }
        fill_table(c->table_rV, 4, crv, y_table32 + yoffs);
        fill_table(c->table_gU, 4, cgu, y_table32 + yoffs + 1024);
        fill_table(c->table_bU, 4, cbu, y_table32 + yoffs + 2048);
        fill_gv_table(c->table_gV, 4, cgv);
        break;
    default:
        c->yuvTable = NULL;
        av_log(c, AV_LOG_ERROR, "%ibpp not supported by yuv2rgb\n", bpp);
        return -1;
    }
    return 0;
}