ffmpeg/libswscale/swscale.c

/*
 * Copyright (C) 2001-2003 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of Libav.
 *
 * Libav 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.
 *
 * Libav 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 Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
  supported Input formats: YV12, I420/IYUV, YUY2, UYVY, BGR32, BGR32_1, BGR24, BGR16, BGR15, RGB32, RGB32_1, RGB24, Y8/Y800, YVU9/IF09, PAL8
  supported output formats: YV12, I420/IYUV, YUY2, UYVY, {BGR,RGB}{1,4,8,15,16,24,32}, Y8/Y800, YVU9/IF09
  {BGR,RGB}{1,4,8,15,16} support dithering

  unscaled special converters (YV12=I420=IYUV, Y800=Y8)
  YV12 -> {BGR,RGB}{1,4,8,12,15,16,24,32}
  x -> x
  YUV9 -> YV12
  YUV9/YV12 -> Y800
  Y800 -> YUV9/YV12
  BGR24 -> BGR32 & RGB24 -> RGB32
  BGR32 -> BGR24 & RGB32 -> RGB24
  BGR15 -> BGR16
*/

/*
tested special converters (most are tested actually, but I did not write it down ...)
 YV12 -> BGR12/BGR16
 YV12 -> YV12
 BGR15 -> BGR16
 BGR16 -> BGR16
 YVU9 -> YV12

untested special converters
  YV12/I420 -> BGR15/BGR24/BGR32 (it is the yuv2rgb stuff, so it should be OK)
  YV12/I420 -> YV12/I420
  YUY2/BGR15/BGR24/BGR32/RGB24/RGB32 -> same format
  BGR24 -> BGR32 & RGB24 -> RGB32
  BGR32 -> BGR24 & RGB32 -> RGB24
  BGR24 -> YV12
*/

#include <inttypes.h>
#include <string.h>
#include <math.h>
#include <stdio.h>
#include "config.h"
#include <assert.h>
#include "swscale.h"
#include "swscale_internal.h"
#include "rgb2rgb.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/cpu.h"
#include "libavutil/avutil.h"
#include "libavutil/mathematics.h"
#include "libavutil/bswap.h"
#include "libavutil/pixdesc.h"

#define DITHER1XBPP

#define RGB2YUV_SHIFT 15
#define BY ( (int)(0.114*219/255*(1<<RGB2YUV_SHIFT)+0.5))
#define BV (-(int)(0.081*224/255*(1<<RGB2YUV_SHIFT)+0.5))
#define BU ( (int)(0.500*224/255*(1<<RGB2YUV_SHIFT)+0.5))
#define GY ( (int)(0.587*219/255*(1<<RGB2YUV_SHIFT)+0.5))
#define GV (-(int)(0.419*224/255*(1<<RGB2YUV_SHIFT)+0.5))
#define GU (-(int)(0.331*224/255*(1<<RGB2YUV_SHIFT)+0.5))
#define RY ( (int)(0.299*219/255*(1<<RGB2YUV_SHIFT)+0.5))
#define RV ( (int)(0.500*224/255*(1<<RGB2YUV_SHIFT)+0.5))
#define RU (-(int)(0.169*224/255*(1<<RGB2YUV_SHIFT)+0.5))

static const double rgb2yuv_table[8][9]={
    {0.7152, 0.0722, 0.2126, -0.386, 0.5, -0.115, -0.454, -0.046, 0.5}, //ITU709
    {0.7152, 0.0722, 0.2126, -0.386, 0.5, -0.115, -0.454, -0.046, 0.5}, //ITU709
    {0.587 , 0.114 , 0.299 , -0.331, 0.5, -0.169, -0.419, -0.081, 0.5}, //DEFAULT / ITU601 / ITU624 / SMPTE 170M
    {0.587 , 0.114 , 0.299 , -0.331, 0.5, -0.169, -0.419, -0.081, 0.5}, //DEFAULT / ITU601 / ITU624 / SMPTE 170M
    {0.59  , 0.11  , 0.30  , -0.331, 0.5, -0.169, -0.421, -0.079, 0.5}, //FCC
    {0.587 , 0.114 , 0.299 , -0.331, 0.5, -0.169, -0.419, -0.081, 0.5}, //DEFAULT / ITU601 / ITU624 / SMPTE 170M
    {0.587 , 0.114 , 0.299 , -0.331, 0.5, -0.169, -0.419, -0.081, 0.5}, //DEFAULT / ITU601 / ITU624 / SMPTE 170M
    {0.701 , 0.087 , 0.212 , -0.384, 0.5, -0.116, -0.445, -0.055, 0.5}, //SMPTE 240M
};

/*
NOTES
Special versions: fast Y 1:1 scaling (no interpolation in y direction)

TODO
more intelligent misalignment avoidance for the horizontal scaler
write special vertical cubic upscale version
optimize C code (YV12 / minmax)
add support for packed pixel YUV input & output
add support for Y8 output
optimize BGR24 & BGR32
add BGR4 output support
write special BGR->BGR scaler
*/

DECLARE_ALIGNED(8, static const uint8_t, dither_2x2_4)[2][8]={
{  1,   3,   1,   3,   1,   3,   1,   3, },
{  2,   0,   2,   0,   2,   0,   2,   0, },
};

DECLARE_ALIGNED(8, static const uint8_t, dither_2x2_8)[2][8]={
{  6,   2,   6,   2,   6,   2,   6,   2, },
{  0,   4,   0,   4,   0,   4,   0,   4, },
};

DECLARE_ALIGNED(8, const uint8_t, dither_4x4_16)[4][8]={
{  8,   4,  11,   7,   8,   4,  11,   7, },
{  2,  14,   1,  13,   2,  14,   1,  13, },
{ 10,   6,   9,   5,  10,   6,   9,   5, },
{  0,  12,   3,  15,   0,  12,   3,  15, },
};

DECLARE_ALIGNED(8, const uint8_t, dither_8x8_32)[8][8]={
{ 17,   9,  23,  15,  16,   8,  22,  14, },
{  5,  29,   3,  27,   4,  28,   2,  26, },
{ 21,  13,  19,  11,  20,  12,  18,  10, },
{  0,  24,   6,  30,   1,  25,   7,  31, },
{ 16,   8,  22,  14,  17,   9,  23,  15, },
{  4,  28,   2,  26,   5,  29,   3,  27, },
{ 20,  12,  18,  10,  21,  13,  19,  11, },
{  1,  25,   7,  31,   0,  24,   6,  30, },
};

DECLARE_ALIGNED(8, const uint8_t, dither_8x8_73)[8][8]={
{  0,  55,  14,  68,   3,  58,  17,  72, },
{ 37,  18,  50,  32,  40,  22,  54,  35, },
{  9,  64,   5,  59,  13,  67,   8,  63, },
{ 46,  27,  41,  23,  49,  31,  44,  26, },
{  2,  57,  16,  71,   1,  56,  15,  70, },
{ 39,  21,  52,  34,  38,  19,  51,  33, },
{ 11,  66,   7,  62,  10,  65,   6,  60, },
{ 48,  30,  43,  25,  47,  29,  42,  24, },
};

#if 1
DECLARE_ALIGNED(8, const uint8_t, dither_8x8_220)[8][8]={
{117,  62, 158, 103, 113,  58, 155, 100, },
{ 34, 199,  21, 186,  31, 196,  17, 182, },
{144,  89, 131,  76, 141,  86, 127,  72, },
{  0, 165,  41, 206,  10, 175,  52, 217, },
{110,  55, 151,  96, 120,  65, 162, 107, },
{ 28, 193,  14, 179,  38, 203,  24, 189, },
{138,  83, 124,  69, 148,  93, 134,  79, },
{  7, 172,  48, 213,   3, 168,  45, 210, },
};
#elif 1
// tries to correct a gamma of 1.5
DECLARE_ALIGNED(8, const uint8_t, dither_8x8_220)[8][8]={
{  0, 143,  18, 200,   2, 156,  25, 215, },
{ 78,  28, 125,  64,  89,  36, 138,  74, },
{ 10, 180,   3, 161,  16, 195,   8, 175, },
{109,  51,  93,  38, 121,  60, 105,  47, },
{  1, 152,  23, 210,   0, 147,  20, 205, },
{ 85,  33, 134,  71,  81,  30, 130,  67, },
{ 14, 190,   6, 171,  12, 185,   5, 166, },
{117,  57, 101,  44, 113,  54,  97,  41, },
};
#elif 1
// tries to correct a gamma of 2.0
DECLARE_ALIGNED(8, const uint8_t, dither_8x8_220)[8][8]={
{  0, 124,   8, 193,   0, 140,  12, 213, },
{ 55,  14, 104,  42,  66,  19, 119,  52, },
{  3, 168,   1, 145,   6, 187,   3, 162, },
{ 86,  31,  70,  21,  99,  39,  82,  28, },
{  0, 134,  11, 206,   0, 129,   9, 200, },
{ 62,  17, 114,  48,  58,  16, 109,  45, },
{  5, 181,   2, 157,   4, 175,   1, 151, },
{ 95,  36,  78,  26,  90,  34,  74,  24, },
};
#else
// tries to correct a gamma of 2.5
DECLARE_ALIGNED(8, const uint8_t, dither_8x8_220)[8][8]={
{  0, 107,   3, 187,   0, 125,   6, 212, },
{ 39,   7,  86,  28,  49,  11, 102,  36, },
{  1, 158,   0, 131,   3, 180,   1, 151, },
{ 68,  19,  52,  12,  81,  25,  64,  17, },
{  0, 119,   5, 203,   0, 113,   4, 195, },
{ 45,   9,  96,  33,  42,   8,  91,  30, },
{  2, 172,   1, 144,   2, 165,   0, 137, },
{ 77,  23,  60,  15,  72,  21,  56,  14, },
};
#endif

static av_always_inline void
yuv2yuvX16_c_template(const int16_t *lumFilter, const int16_t **lumSrc,
                      int lumFilterSize, const int16_t *chrFilter,
                      const int16_t **chrUSrc, const int16_t **chrVSrc,
                      int chrFilterSize, const int16_t **alpSrc,
                      uint16_t *dest, uint16_t *uDest, uint16_t *vDest,
                      uint16_t *aDest, int dstW, int chrDstW,
                      int big_endian, int output_bits)
{
    //FIXME Optimize (just quickly written not optimized..)
    int i;
    int shift = 11 + 16 - output_bits;

#define output_pixel(pos, val) \
    if (big_endian) { \
        if (output_bits == 16) { \
            AV_WB16(pos, av_clip_uint16(val >> shift)); \
        } else { \
            AV_WB16(pos, av_clip_uintp2(val >> shift, output_bits)); \
        } \
    } else { \
        if (output_bits == 16) { \
            AV_WL16(pos, av_clip_uint16(val >> shift)); \
        } else { \
            AV_WL16(pos, av_clip_uintp2(val >> shift, output_bits)); \
        } \
    }
    for (i = 0; i < dstW; i++) {
        int val = 1 << (26-output_bits);
        int j;

        for (j = 0; j < lumFilterSize; j++)
            val += lumSrc[j][i] * lumFilter[j];

        output_pixel(&dest[i], val);
    }

    if (uDest) {
        for (i = 0; i < chrDstW; i++) {
            int u = 1 << (26-output_bits);
            int v = 1 << (26-output_bits);
            int j;

            for (j = 0; j < chrFilterSize; j++) {
                u += chrUSrc[j][i] * chrFilter[j];
                v += chrVSrc[j][i] * chrFilter[j];
            }

            output_pixel(&uDest[i], u);
            output_pixel(&vDest[i], v);
        }
    }

    if (CONFIG_SWSCALE_ALPHA && aDest) {
        for (i = 0; i < dstW; i++) {
            int val = 1 << (26-output_bits);
            int j;

            for (j = 0; j < lumFilterSize; j++)
                val += alpSrc[j][i] * lumFilter[j];

            output_pixel(&aDest[i], val);
        }
    }
#undef output_pixel
}

#define yuv2NBPS(bits, BE_LE, is_be) \
static void yuv2yuvX ## bits ## BE_LE ## _c(SwsContext *c, const int16_t *lumFilter, \
                              const int16_t **lumSrc, int lumFilterSize, \
                              const int16_t *chrFilter, const int16_t **chrUSrc, \
                              const int16_t **chrVSrc, \
                              int chrFilterSize, const int16_t **alpSrc, \
                              uint8_t *_dest, uint8_t *_uDest, uint8_t *_vDest, \
                              uint8_t *_aDest, int dstW, int chrDstW) \
{ \
    uint16_t *dest  = (uint16_t *) _dest,  *uDest = (uint16_t *) _uDest, \
             *vDest = (uint16_t *) _vDest, *aDest = (uint16_t *) _aDest; \
    yuv2yuvX16_c_template(lumFilter, lumSrc, lumFilterSize, \
                          chrFilter, chrUSrc, chrVSrc, chrFilterSize, \
                          alpSrc, \
                          dest, uDest, vDest, aDest, \
                          dstW, chrDstW, is_be, bits); \
}
yuv2NBPS( 9, BE, 1);
yuv2NBPS( 9, LE, 0);
yuv2NBPS(10, BE, 1);
yuv2NBPS(10, LE, 0);
yuv2NBPS(16, BE, 1);
yuv2NBPS(16, LE, 0);

static inline void yuv2yuvX16_c(SwsContext *c, const int16_t *lumFilter, const int16_t **lumSrc, int lumFilterSize,
                                const int16_t *chrFilter, const int16_t **chrUSrc, const int16_t **chrVSrc, int chrFilterSize,
                                const int16_t **alpSrc, uint8_t *dest, uint8_t *uDest, uint8_t *vDest, uint8_t *aDest, int dstW, int chrDstW,
                                enum PixelFormat dstFormat)
{
#define conv16(bits) \
    if (isBE(dstFormat)) { \
        yuv2yuvX ## bits ## BE_c(c, lumFilter, lumSrc, lumFilterSize, \
                                 chrFilter, chrUSrc, chrVSrc, chrFilterSize, \
                                 alpSrc, \
                                 dest, uDest, vDest, aDest, \
                                 dstW, chrDstW); \
    } else { \
        yuv2yuvX ## bits ## LE_c(c, lumFilter, lumSrc, lumFilterSize, \
                                 chrFilter, chrUSrc, chrVSrc, chrFilterSize, \
                                 alpSrc, \
                                 dest, uDest, vDest, aDest, \
                                 dstW, chrDstW); \
    }
    if (is16BPS(dstFormat)) {
        conv16(16);
    } else if (av_pix_fmt_descriptors[dstFormat].comp[0].depth_minus1 == 8) {
        conv16(9);
    } else {
        conv16(10);
    }
#undef conv16
}

static inline void yuv2yuvX_c(SwsContext *c, const int16_t *lumFilter,
                              const int16_t **lumSrc, int lumFilterSize,
                              const int16_t *chrFilter, const int16_t **chrUSrc,
                              const int16_t **chrVSrc,
                              int chrFilterSize, const int16_t **alpSrc,
                              uint8_t *dest, uint8_t *uDest, uint8_t *vDest,
                              uint8_t *aDest, int dstW, int chrDstW)
{
    //FIXME Optimize (just quickly written not optimized..)
    int i;
    for (i=0; i<dstW; i++) {
        int val=1<<18;
        int j;
        for (j=0; j<lumFilterSize; j++)
            val += lumSrc[j][i] * lumFilter[j];

        dest[i]= av_clip_uint8(val>>19);
    }

    if (uDest)
        for (i=0; i<chrDstW; i++) {
            int u=1<<18;
            int v=1<<18;
            int j;
            for (j=0; j<chrFilterSize; j++) {
                u += chrUSrc[j][i] * chrFilter[j];
                v += chrVSrc[j][i] * chrFilter[j];
            }

            uDest[i]= av_clip_uint8(u>>19);
            vDest[i]= av_clip_uint8(v>>19);
        }

    if (CONFIG_SWSCALE_ALPHA && aDest)
        for (i=0; i<dstW; i++) {
            int val=1<<18;
            int j;
            for (j=0; j<lumFilterSize; j++)
                val += alpSrc[j][i] * lumFilter[j];

            aDest[i]= av_clip_uint8(val>>19);
        }

}

static inline void yuv2nv12X_c(SwsContext *c, const int16_t *lumFilter,
                               const int16_t **lumSrc, int lumFilterSize,
                               const int16_t *chrFilter, const int16_t **chrUSrc,
                               const int16_t **chrVSrc, int chrFilterSize,
                               const int16_t **alpSrc, uint8_t *dest, uint8_t *uDest,
                               uint8_t *vDest, uint8_t *aDest,
                               int dstW, int chrDstW)
{
    enum PixelFormat dstFormat = c->dstFormat;

    //FIXME Optimize (just quickly written not optimized..)
    int i;
    for (i=0; i<dstW; i++) {
        int val=1<<18;
        int j;
        for (j=0; j<lumFilterSize; j++)
            val += lumSrc[j][i] * lumFilter[j];

        dest[i]= av_clip_uint8(val>>19);
    }

    if (!uDest)
        return;

    if (dstFormat == PIX_FMT_NV12)
        for (i=0; i<chrDstW; i++) {
            int u=1<<18;
            int v=1<<18;
            int j;
            for (j=0; j<chrFilterSize; j++) {
                u += chrUSrc[j][i] * chrFilter[j];
                v += chrVSrc[j][i] * chrFilter[j];
            }

            uDest[2*i]= av_clip_uint8(u>>19);
            uDest[2*i+1]= av_clip_uint8(v>>19);
        }
    else
        for (i=0; i<chrDstW; i++) {
            int u=1<<18;
            int v=1<<18;
            int j;
            for (j=0; j<chrFilterSize; j++) {
                u += chrUSrc[j][i] * chrFilter[j];
                v += chrVSrc[j][i] * chrFilter[j];
            }

            uDest[2*i]= av_clip_uint8(v>>19);
            uDest[2*i+1]= av_clip_uint8(u>>19);
        }
}

#define YSCALE_YUV_2_PACKEDX_NOCLIP_C(type,alpha) \
    for (i=0; i<(dstW>>1); i++) {\
        int j;\
        int Y1 = 1<<18;\
        int Y2 = 1<<18;\
        int U  = 1<<18;\
        int V  = 1<<18;\
        int av_unused A1, A2;\
        type av_unused *r, *b, *g;\
        const int i2= 2*i;\
        \
        for (j=0; j<lumFilterSize; j++) {\
            Y1 += lumSrc[j][i2] * lumFilter[j];\
            Y2 += lumSrc[j][i2+1] * lumFilter[j];\
        }\
        for (j=0; j<chrFilterSize; j++) {\
            U += chrUSrc[j][i] * chrFilter[j];\
            V += chrVSrc[j][i] * chrFilter[j];\
        }\
        Y1>>=19;\
        Y2>>=19;\
        U >>=19;\
        V >>=19;\
        if (alpha) {\
            A1 = 1<<18;\
            A2 = 1<<18;\
            for (j=0; j<lumFilterSize; j++) {\
                A1 += alpSrc[j][i2  ] * lumFilter[j];\
                A2 += alpSrc[j][i2+1] * lumFilter[j];\
            }\
            A1>>=19;\
            A2>>=19;\
        }

#define YSCALE_YUV_2_PACKEDX_C(type,alpha) \
        YSCALE_YUV_2_PACKEDX_NOCLIP_C(type,alpha)\
        if ((Y1|Y2|U|V)&256) {\
            if (Y1>255)   Y1=255; \
            else if (Y1<0)Y1=0;   \
            if (Y2>255)   Y2=255; \
            else if (Y2<0)Y2=0;   \
            if (U>255)    U=255;  \
            else if (U<0) U=0;    \
            if (V>255)    V=255;  \
            else if (V<0) V=0;    \
        }\
        if (alpha && ((A1|A2)&256)) {\
            A1=av_clip_uint8(A1);\
            A2=av_clip_uint8(A2);\
        }

#define YSCALE_YUV_2_PACKEDX_FULL_C(rnd,alpha) \
    for (i=0; i<dstW; i++) {\
        int j;\
        int Y = 0;\
        int U = -128<<19;\
        int V = -128<<19;\
        int av_unused A;\
        int R,G,B;\
        \
        for (j=0; j<lumFilterSize; j++) {\
            Y += lumSrc[j][i     ] * lumFilter[j];\
        }\
        for (j=0; j<chrFilterSize; j++) {\
            U += chrUSrc[j][i] * chrFilter[j];\
            V += chrVSrc[j][i] * chrFilter[j];\
        }\
        Y >>=10;\
        U >>=10;\
        V >>=10;\
        if (alpha) {\
            A = rnd;\
            for (j=0; j<lumFilterSize; j++)\
                A += alpSrc[j][i     ] * lumFilter[j];\
            A >>=19;\
            if (A&256)\
                A = av_clip_uint8(A);\
        }

#define YSCALE_YUV_2_RGBX_FULL_C(rnd,alpha) \
    YSCALE_YUV_2_PACKEDX_FULL_C(rnd>>3,alpha)\
        Y-= c->yuv2rgb_y_offset;\
        Y*= c->yuv2rgb_y_coeff;\
        Y+= rnd;\
        R= Y + V*c->yuv2rgb_v2r_coeff;\
        G= Y + V*c->yuv2rgb_v2g_coeff + U*c->yuv2rgb_u2g_coeff;\
        B= Y +                          U*c->yuv2rgb_u2b_coeff;\
        if ((R|G|B)&(0xC0000000)) {\
            if (R>=(256<<22))   R=(256<<22)-1; \
            else if (R<0)R=0;   \
            if (G>=(256<<22))   G=(256<<22)-1; \
            else if (G<0)G=0;   \
            if (B>=(256<<22))   B=(256<<22)-1; \
            else if (B<0)B=0;   \
        }

#define YSCALE_YUV_2_GRAY16_C \
    for (i=0; i<(dstW>>1); i++) {\
        int j;\
        int Y1 = 1<<18;\
        int Y2 = 1<<18;\
        int U  = 1<<18;\
        int V  = 1<<18;\
        \
        const int i2= 2*i;\
        \
        for (j=0; j<lumFilterSize; j++) {\
            Y1 += lumSrc[j][i2] * lumFilter[j];\
            Y2 += lumSrc[j][i2+1] * lumFilter[j];\
        }\
        Y1>>=11;\
        Y2>>=11;\
        if ((Y1|Y2|U|V)&65536) {\
            if (Y1>65535)   Y1=65535; \
            else if (Y1<0)Y1=0;   \
            if (Y2>65535)   Y2=65535; \
            else if (Y2<0)Y2=0;   \
        }

#define YSCALE_YUV_2_RGBX_C(type,alpha) \
    YSCALE_YUV_2_PACKEDX_C(type,alpha)  /* FIXME fix tables so that clipping is not needed and then use _NOCLIP*/\
    r = (type *)c->table_rV[V];   \
    g = (type *)(c->table_gU[U] + c->table_gV[V]); \
    b = (type *)c->table_bU[U];

#define YSCALE_YUV_2_PACKED2_C(type,alpha)   \
    for (i=0; i<(dstW>>1); i++) { \
        const int i2= 2*i;       \
        int Y1= (buf0[i2  ]*yalpha1+buf1[i2  ]*yalpha)>>19;           \
        int Y2= (buf0[i2+1]*yalpha1+buf1[i2+1]*yalpha)>>19;           \
        int U= (ubuf0[i]*uvalpha1+ubuf1[i]*uvalpha)>>19;              \
        int V= (vbuf0[i]*uvalpha1+vbuf1[i]*uvalpha)>>19;              \
        type av_unused *r, *b, *g;                                    \
        int av_unused A1, A2;                                         \
        if (alpha) {\
            A1= (abuf0[i2  ]*yalpha1+abuf1[i2  ]*yalpha)>>19;         \
            A2= (abuf0[i2+1]*yalpha1+abuf1[i2+1]*yalpha)>>19;         \
        }

#define YSCALE_YUV_2_GRAY16_2_C   \
    for (i=0; i<(dstW>>1); i++) { \
        const int i2= 2*i;       \
        int Y1= (buf0[i2  ]*yalpha1+buf1[i2  ]*yalpha)>>11;           \
        int Y2= (buf0[i2+1]*yalpha1+buf1[i2+1]*yalpha)>>11;

#define YSCALE_YUV_2_RGB2_C(type,alpha) \
    YSCALE_YUV_2_PACKED2_C(type,alpha)\
    r = (type *)c->table_rV[V];\
    g = (type *)(c->table_gU[U] + c->table_gV[V]);\
    b = (type *)c->table_bU[U];

#define YSCALE_YUV_2_PACKED1_C(type,alpha) \
    for (i=0; i<(dstW>>1); i++) {\
        const int i2= 2*i;\
        int Y1= buf0[i2  ]>>7;\
        int Y2= buf0[i2+1]>>7;\
        int U= (ubuf1[i])>>7;\
        int V= (vbuf1[i])>>7;\
        type av_unused *r, *b, *g;\
        int av_unused A1, A2;\
        if (alpha) {\
            A1= abuf0[i2  ]>>7;\
            A2= abuf0[i2+1]>>7;\
        }

#define YSCALE_YUV_2_GRAY16_1_C \
    for (i=0; i<(dstW>>1); i++) {\
        const int i2= 2*i;\
        int Y1= buf0[i2  ]<<1;\
        int Y2= buf0[i2+1]<<1;

#define YSCALE_YUV_2_RGB1_C(type,alpha) \
    YSCALE_YUV_2_PACKED1_C(type,alpha)\
    r = (type *)c->table_rV[V];\
    g = (type *)(c->table_gU[U] + c->table_gV[V]);\
    b = (type *)c->table_bU[U];

#define YSCALE_YUV_2_PACKED1B_C(type,alpha) \
    for (i=0; i<(dstW>>1); i++) {\
        const int i2= 2*i;\
        int Y1= buf0[i2  ]>>7;\
        int Y2= buf0[i2+1]>>7;\
        int U= (ubuf0[i] + ubuf1[i])>>8;\
        int V= (vbuf0[i] + vbuf1[i])>>8;\
        type av_unused *r, *b, *g;\
        int av_unused A1, A2;\
        if (alpha) {\
            A1= abuf0[i2  ]>>7;\
            A2= abuf0[i2+1]>>7;\
        }

#define YSCALE_YUV_2_RGB1B_C(type,alpha) \
    YSCALE_YUV_2_PACKED1B_C(type,alpha)\
    r = (type *)c->table_rV[V];\
    g = (type *)(c->table_gU[U] + c->table_gV[V]);\
    b = (type *)c->table_bU[U];

#define YSCALE_YUV_2_MONO2_C \
    const uint8_t * const d128=dither_8x8_220[y&7];\
    uint8_t *g= c->table_gU[128] + c->table_gV[128];\
    for (i=0; i<dstW-7; i+=8) {\
        int acc;\
        acc =       g[((buf0[i  ]*yalpha1+buf1[i  ]*yalpha)>>19) + d128[0]];\
        acc+= acc + g[((buf0[i+1]*yalpha1+buf1[i+1]*yalpha)>>19) + d128[1]];\
        acc+= acc + g[((buf0[i+2]*yalpha1+buf1[i+2]*yalpha)>>19) + d128[2]];\
        acc+= acc + g[((buf0[i+3]*yalpha1+buf1[i+3]*yalpha)>>19) + d128[3]];\
        acc+= acc + g[((buf0[i+4]*yalpha1+buf1[i+4]*yalpha)>>19) + d128[4]];\
        acc+= acc + g[((buf0[i+5]*yalpha1+buf1[i+5]*yalpha)>>19) + d128[5]];\
        acc+= acc + g[((buf0[i+6]*yalpha1+buf1[i+6]*yalpha)>>19) + d128[6]];\
        acc+= acc + g[((buf0[i+7]*yalpha1+buf1[i+7]*yalpha)>>19) + d128[7]];\
        ((uint8_t*)dest)[0]= c->dstFormat == PIX_FMT_MONOBLACK ? acc : ~acc;\
        dest++;\
    }

#define YSCALE_YUV_2_MONOX_C \
    const uint8_t * const d128=dither_8x8_220[y&7];\
    uint8_t *g= c->table_gU[128] + c->table_gV[128];\
    int acc=0;\
    for (i=0; i<dstW-1; i+=2) {\
        int j;\
        int Y1=1<<18;\
        int Y2=1<<18;\
\
        for (j=0; j<lumFilterSize; j++) {\
            Y1 += lumSrc[j][i] * lumFilter[j];\
            Y2 += lumSrc[j][i+1] * lumFilter[j];\
        }\
        Y1>>=19;\
        Y2>>=19;\
        if ((Y1|Y2)&256) {\
            if (Y1>255)   Y1=255;\
            else if (Y1<0)Y1=0;\
            if (Y2>255)   Y2=255;\
            else if (Y2<0)Y2=0;\
        }\
        acc+= acc + g[Y1+d128[(i+0)&7]];\
        acc+= acc + g[Y2+d128[(i+1)&7]];\
        if ((i&7)==6) {\
            ((uint8_t*)dest)[0]= c->dstFormat == PIX_FMT_MONOBLACK ? acc : ~acc;\
            dest++;\
        }\
    }

#define YSCALE_YUV_2_ANYRGB_C(func, func2, func_g16, func_monoblack)\
    switch(c->dstFormat) {\
    case PIX_FMT_RGB48BE:\
    case PIX_FMT_RGB48LE:\
        func(uint8_t,0)\
            ((uint8_t*)dest)[ 0]= r[Y1];\
            ((uint8_t*)dest)[ 1]= r[Y1];\
            ((uint8_t*)dest)[ 2]= g[Y1];\
            ((uint8_t*)dest)[ 3]= g[Y1];\
            ((uint8_t*)dest)[ 4]= b[Y1];\
            ((uint8_t*)dest)[ 5]= b[Y1];\
            ((uint8_t*)dest)[ 6]= r[Y2];\
            ((uint8_t*)dest)[ 7]= r[Y2];\
            ((uint8_t*)dest)[ 8]= g[Y2];\
            ((uint8_t*)dest)[ 9]= g[Y2];\
            ((uint8_t*)dest)[10]= b[Y2];\
            ((uint8_t*)dest)[11]= b[Y2];\
            dest+=12;\
        }\
        break;\
    case PIX_FMT_BGR48BE:\
    case PIX_FMT_BGR48LE:\
        func(uint8_t,0)\
            ((uint8_t*)dest)[ 0] = ((uint8_t*)dest)[ 1] = b[Y1];\
            ((uint8_t*)dest)[ 2] = ((uint8_t*)dest)[ 3] = g[Y1];\
            ((uint8_t*)dest)[ 4] = ((uint8_t*)dest)[ 5] = r[Y1];\
            ((uint8_t*)dest)[ 6] = ((uint8_t*)dest)[ 7] = b[Y2];\
            ((uint8_t*)dest)[ 8] = ((uint8_t*)dest)[ 9] = g[Y2];\
            ((uint8_t*)dest)[10] = ((uint8_t*)dest)[11] = r[Y2];\
            dest+=12;\
        }\
        break;\
    case PIX_FMT_RGBA:\
    case PIX_FMT_BGRA:\
        if (CONFIG_SMALL) {\
            int needAlpha = CONFIG_SWSCALE_ALPHA && c->alpPixBuf;\
            func(uint32_t,needAlpha)\
                ((uint32_t*)dest)[i2+0]= r[Y1] + g[Y1] + b[Y1] + (needAlpha ? (A1<<24) : 0);\
                ((uint32_t*)dest)[i2+1]= r[Y2] + g[Y2] + b[Y2] + (needAlpha ? (A2<<24) : 0);\
            }\
        } else {\
            if (CONFIG_SWSCALE_ALPHA && c->alpPixBuf) {\
                func(uint32_t,1)\
                    ((uint32_t*)dest)[i2+0]= r[Y1] + g[Y1] + b[Y1] + (A1<<24);\
                    ((uint32_t*)dest)[i2+1]= r[Y2] + g[Y2] + b[Y2] + (A2<<24);\
                }\
            } else {\
                func(uint32_t,0)\
                    ((uint32_t*)dest)[i2+0]= r[Y1] + g[Y1] + b[Y1];\
                    ((uint32_t*)dest)[i2+1]= r[Y2] + g[Y2] + b[Y2];\
                }\
            }\
        }\
        break;\
    case PIX_FMT_ARGB:\
    case PIX_FMT_ABGR:\
        if (CONFIG_SMALL) {\
            int needAlpha = CONFIG_SWSCALE_ALPHA && c->alpPixBuf;\
            func(uint32_t,needAlpha)\
                ((uint32_t*)dest)[i2+0]= r[Y1] + g[Y1] + b[Y1] + (needAlpha ? A1 : 0);\
                ((uint32_t*)dest)[i2+1]= r[Y2] + g[Y2] + b[Y2] + (needAlpha ? A2 : 0);\
            }\
        } else {\
            if (CONFIG_SWSCALE_ALPHA && c->alpPixBuf) {\
                func(uint32_t,1)\
                    ((uint32_t*)dest)[i2+0]= r[Y1] + g[Y1] + b[Y1] + A1;\
                    ((uint32_t*)dest)[i2+1]= r[Y2] + g[Y2] + b[Y2] + A2;\
                }\
            } else {\
                func(uint32_t,0)\
                    ((uint32_t*)dest)[i2+0]= r[Y1] + g[Y1] + b[Y1];\
                    ((uint32_t*)dest)[i2+1]= r[Y2] + g[Y2] + b[Y2];\
                }\
            }\
        }                \
        break;\
    case PIX_FMT_RGB24:\
        func(uint8_t,0)\
            ((uint8_t*)dest)[0]= r[Y1];\
            ((uint8_t*)dest)[1]= g[Y1];\
            ((uint8_t*)dest)[2]= b[Y1];\
            ((uint8_t*)dest)[3]= r[Y2];\
            ((uint8_t*)dest)[4]= g[Y2];\
            ((uint8_t*)dest)[5]= b[Y2];\
            dest+=6;\
        }\
        break;\
    case PIX_FMT_BGR24:\
        func(uint8_t,0)\
            ((uint8_t*)dest)[0]= b[Y1];\
            ((uint8_t*)dest)[1]= g[Y1];\
            ((uint8_t*)dest)[2]= r[Y1];\
            ((uint8_t*)dest)[3]= b[Y2];\
            ((uint8_t*)dest)[4]= g[Y2];\
            ((uint8_t*)dest)[5]= r[Y2];\
            dest+=6;\
        }\
        break;\
    case PIX_FMT_RGB565BE:\
    case PIX_FMT_RGB565LE:\
    case PIX_FMT_BGR565BE:\
    case PIX_FMT_BGR565LE:\
        {\
            const int dr1= dither_2x2_8[y&1    ][0];\
            const int dg1= dither_2x2_4[y&1    ][0];\
            const int db1= dither_2x2_8[(y&1)^1][0];\
            const int dr2= dither_2x2_8[y&1    ][1];\
            const int dg2= dither_2x2_4[y&1    ][1];\
            const int db2= dither_2x2_8[(y&1)^1][1];\
            func(uint16_t,0)\
                ((uint16_t*)dest)[i2+0]= r[Y1+dr1] + g[Y1+dg1] + b[Y1+db1];\
                ((uint16_t*)dest)[i2+1]= r[Y2+dr2] + g[Y2+dg2] + b[Y2+db2];\
            }\
        }\
        break;\
    case PIX_FMT_RGB555BE:\
    case PIX_FMT_RGB555LE:\
    case PIX_FMT_BGR555BE:\
    case PIX_FMT_BGR555LE:\
        {\
            const int dr1= dither_2x2_8[y&1    ][0];\
            const int dg1= dither_2x2_8[y&1    ][1];\
            const int db1= dither_2x2_8[(y&1)^1][0];\
            const int dr2= dither_2x2_8[y&1    ][1];\
            const int dg2= dither_2x2_8[y&1    ][0];\
            const int db2= dither_2x2_8[(y&1)^1][1];\
            func(uint16_t,0)\
                ((uint16_t*)dest)[i2+0]= r[Y1+dr1] + g[Y1+dg1] + b[Y1+db1];\
                ((uint16_t*)dest)[i2+1]= r[Y2+dr2] + g[Y2+dg2] + b[Y2+db2];\
            }\
        }\
        break;\
    case PIX_FMT_RGB444BE:\
    case PIX_FMT_RGB444LE:\
    case PIX_FMT_BGR444BE:\
    case PIX_FMT_BGR444LE:\
        {\
            const int dr1= dither_4x4_16[y&3    ][0];\
            const int dg1= dither_4x4_16[y&3    ][1];\
            const int db1= dither_4x4_16[(y&3)^3][0];\
            const int dr2= dither_4x4_16[y&3    ][1];\
            const int dg2= dither_4x4_16[y&3    ][0];\
            const int db2= dither_4x4_16[(y&3)^3][1];\
            func(uint16_t,0)\
                ((uint16_t*)dest)[i2+0]= r[Y1+dr1] + g[Y1+dg1] + b[Y1+db1];\
                ((uint16_t*)dest)[i2+1]= r[Y2+dr2] + g[Y2+dg2] + b[Y2+db2];\
            }\
        }\
        break;\
    case PIX_FMT_RGB8:\
    case PIX_FMT_BGR8:\
        {\
            const uint8_t * const d64= dither_8x8_73[y&7];\
            const uint8_t * const d32= dither_8x8_32[y&7];\
            func(uint8_t,0)\
                ((uint8_t*)dest)[i2+0]= r[Y1+d32[(i2+0)&7]] + g[Y1+d32[(i2+0)&7]] + b[Y1+d64[(i2+0)&7]];\
                ((uint8_t*)dest)[i2+1]= r[Y2+d32[(i2+1)&7]] + g[Y2+d32[(i2+1)&7]] + b[Y2+d64[(i2+1)&7]];\
            }\
        }\
        break;\
    case PIX_FMT_RGB4:\
    case PIX_FMT_BGR4:\
        {\
            const uint8_t * const d64= dither_8x8_73 [y&7];\
            const uint8_t * const d128=dither_8x8_220[y&7];\
            func(uint8_t,0)\
                ((uint8_t*)dest)[i]= r[Y1+d128[(i2+0)&7]] + g[Y1+d64[(i2+0)&7]] + b[Y1+d128[(i2+0)&7]]\
                                 + ((r[Y2+d128[(i2+1)&7]] + g[Y2+d64[(i2+1)&7]] + b[Y2+d128[(i2+1)&7]])<<4);\
            }\
        }\
        break;\
    case PIX_FMT_RGB4_BYTE:\
    case PIX_FMT_BGR4_BYTE:\
        {\
            const uint8_t * const d64= dither_8x8_73 [y&7];\
            const uint8_t * const d128=dither_8x8_220[y&7];\
            func(uint8_t,0)\
                ((uint8_t*)dest)[i2+0]= r[Y1+d128[(i2+0)&7]] + g[Y1+d64[(i2+0)&7]] + b[Y1+d128[(i2+0)&7]];\
                ((uint8_t*)dest)[i2+1]= r[Y2+d128[(i2+1)&7]] + g[Y2+d64[(i2+1)&7]] + b[Y2+d128[(i2+1)&7]];\
            }\
        }\
        break;\
    case PIX_FMT_MONOBLACK:\
    case PIX_FMT_MONOWHITE:\
        {\
            func_monoblack\
        }\
        break;\
    case PIX_FMT_YUYV422:\
        func2\
            ((uint8_t*)dest)[2*i2+0]= Y1;\
            ((uint8_t*)dest)[2*i2+1]= U;\
            ((uint8_t*)dest)[2*i2+2]= Y2;\
            ((uint8_t*)dest)[2*i2+3]= V;\
        }                \
        break;\
    case PIX_FMT_UYVY422:\
        func2\
            ((uint8_t*)dest)[2*i2+0]= U;\
            ((uint8_t*)dest)[2*i2+1]= Y1;\
            ((uint8_t*)dest)[2*i2+2]= V;\
            ((uint8_t*)dest)[2*i2+3]= Y2;\
        }                \
        break;\
    case PIX_FMT_GRAY16BE:\
        func_g16\
            ((uint8_t*)dest)[2*i2+0]= Y1>>8;\
            ((uint8_t*)dest)[2*i2+1]= Y1;\
            ((uint8_t*)dest)[2*i2+2]= Y2>>8;\
            ((uint8_t*)dest)[2*i2+3]= Y2;\
        }                \
        break;\
    case PIX_FMT_GRAY16LE:\
        func_g16\
            ((uint8_t*)dest)[2*i2+0]= Y1;\
            ((uint8_t*)dest)[2*i2+1]= Y1>>8;\
            ((uint8_t*)dest)[2*i2+2]= Y2;\
            ((uint8_t*)dest)[2*i2+3]= Y2>>8;\
        }                \
        break;\
    }

static void yuv2packedX_c(SwsContext *c, const int16_t *lumFilter,
                          const int16_t **lumSrc, int lumFilterSize,
                          const int16_t *chrFilter, const int16_t **chrUSrc,
                          const int16_t **chrVSrc, int chrFilterSize,
                          const int16_t **alpSrc, uint8_t *dest, int dstW, int y)
{
    int i;
    YSCALE_YUV_2_ANYRGB_C(YSCALE_YUV_2_RGBX_C, YSCALE_YUV_2_PACKEDX_C(void,0), YSCALE_YUV_2_GRAY16_C, YSCALE_YUV_2_MONOX_C)
}

static inline void yuv2rgbX_c_full(SwsContext *c, const int16_t *lumFilter,
                                   const int16_t **lumSrc, int lumFilterSize,
                                   const int16_t *chrFilter, const int16_t **chrUSrc,
                                   const int16_t **chrVSrc, int chrFilterSize,
                                   const int16_t **alpSrc, uint8_t *dest, int dstW, int y)
{
    int i;
    int step= c->dstFormatBpp/8;
    int aidx= 3;

    switch(c->dstFormat) {
    case PIX_FMT_ARGB:
        dest++;
        aidx= 0;
    case PIX_FMT_RGB24:
        aidx--;
    case PIX_FMT_RGBA:
        if (CONFIG_SMALL) {
            int needAlpha = CONFIG_SWSCALE_ALPHA && c->alpPixBuf;
            YSCALE_YUV_2_RGBX_FULL_C(1<<21, needAlpha)
                dest[aidx]= needAlpha ? A : 255;
                dest[0]= R>>22;
                dest[1]= G>>22;
                dest[2]= B>>22;
                dest+= step;
            }
        } else {
            if (CONFIG_SWSCALE_ALPHA && c->alpPixBuf) {
                YSCALE_YUV_2_RGBX_FULL_C(1<<21, 1)
                    dest[aidx]= A;
                    dest[0]= R>>22;
                    dest[1]= G>>22;
                    dest[2]= B>>22;
                    dest+= step;
                }
            } else {
                YSCALE_YUV_2_RGBX_FULL_C(1<<21, 0)
                    dest[aidx]= 255;
                    dest[0]= R>>22;
                    dest[1]= G>>22;
                    dest[2]= B>>22;
                    dest+= step;
                }
            }
        }
        break;
    case PIX_FMT_ABGR:
        dest++;
        aidx= 0;
    case PIX_FMT_BGR24:
        aidx--;
    case PIX_FMT_BGRA:
        if (CONFIG_SMALL) {
            int needAlpha = CONFIG_SWSCALE_ALPHA && c->alpPixBuf;
            YSCALE_YUV_2_RGBX_FULL_C(1<<21, needAlpha)
                dest[aidx]= needAlpha ? A : 255;
                dest[0]= B>>22;
                dest[1]= G>>22;
                dest[2]= R>>22;
                dest+= step;
            }
        } else {
            if (CONFIG_SWSCALE_ALPHA && c->alpPixBuf) {
                YSCALE_YUV_2_RGBX_FULL_C(1<<21, 1)
                    dest[aidx]= A;
                    dest[0]= B>>22;
                    dest[1]= G>>22;
                    dest[2]= R>>22;
                    dest+= step;
                }
            } else {
                YSCALE_YUV_2_RGBX_FULL_C(1<<21, 0)
                    dest[aidx]= 255;
                    dest[0]= B>>22;
                    dest[1]= G>>22;
                    dest[2]= R>>22;
                    dest+= step;
                }
            }
        }
        break;
    default:
        assert(0);
    }
}

static void fillPlane(uint8_t* plane, int stride, int width, int height, int y, uint8_t val)
{
    int i;
    uint8_t *ptr = plane + stride*y;
    for (i=0; i<height; i++) {
        memset(ptr, val, width);
        ptr += stride;
    }
}

#define rgb48funcs(LE_BE, rfunc, compA, compB, compC) \
static void compA ## compB ## compC ## 48 ## LE_BE ## ToY_c( \
                       uint8_t *dst, const uint8_t *src, int width, \
                       uint32_t *unused) \
{ \
    int i; \
    for (i = 0; i < width; i++) { \
        int compA = rfunc(&src[i*6+0]) >> 8; \
        int compB = rfunc(&src[i*6+2]) >> 8; \
        int compC = rfunc(&src[i*6+4]) >> 8; \
 \
        dst[i] = (RY*r + GY*g + BY*b + (33<<(RGB2YUV_SHIFT-1))) >> RGB2YUV_SHIFT; \
    } \
} \
 \
static void compA ## compB ## compC ## 48 ## LE_BE ## ToUV_c( \
                        uint8_t *dstU, uint8_t *dstV, \
                        const uint8_t *src1, const uint8_t *src2, \
                        int width, uint32_t *unused) \
{ \
    int i; \
    assert(src1==src2); \
    for (i = 0; i < width; i++) { \
        int compA = rfunc(&src1[6*i + 0]) >> 8; \
        int compB = rfunc(&src1[6*i + 2]) >> 8; \
        int compC = rfunc(&src1[6*i + 4]) >> 8; \
 \
        dstU[i] = (RU*r + GU*g + BU*b + (257<<(RGB2YUV_SHIFT-1))) >> RGB2YUV_SHIFT; \
        dstV[i] = (RV*r + GV*g + BV*b + (257<<(RGB2YUV_SHIFT-1))) >> RGB2YUV_SHIFT; \
    } \
} \
 \
static void compA ## compB ## compC ## 48 ## LE_BE ## ToUV_half_c( \
                            uint8_t *dstU, uint8_t *dstV, \
                            const uint8_t *src1, const uint8_t *src2, \
                            int width, uint32_t *unused) \
{ \
    int i; \
    assert(src1==src2); \
    for (i = 0; i < width; i++) { \
        int compA = (rfunc(&src1[12*i + 0]) >> 8) + (rfunc(&src1[12*i + 6]) >> 8); \
        int compB = (rfunc(&src1[12*i + 2]) >> 8) + (rfunc(&src1[12*i + 8]) >> 8); \
        int compC = (rfunc(&src1[12*i + 4]) >> 8) + (rfunc(&src1[12*i + 10]) >> 8); \
 \
        dstU[i]= (RU*r + GU*g + BU*b + (257<<RGB2YUV_SHIFT)) >> (RGB2YUV_SHIFT+1); \
        dstV[i]= (RV*r + GV*g + BV*b + (257<<RGB2YUV_SHIFT)) >> (RGB2YUV_SHIFT+1); \
    } \
}
rgb48funcs(LE, AV_RL16, r, g, b);
rgb48funcs(BE, AV_RB16, r, g, b);
rgb48funcs(LE, AV_RL16, b, g, r);
rgb48funcs(BE, AV_RB16, b, g, r);

#define BGR2Y(type, name, shr, shg, shb, maskr, maskg, maskb, RY, GY, BY, S)\
static void name ## _c(uint8_t *dst, const uint8_t *src, \
                       int width, uint32_t *unused)\
{\
    int i;\
    for (i=0; i<width; i++) {\
        int b= (((const type*)src)[i]>>shb)&maskb;\
        int g= (((const type*)src)[i]>>shg)&maskg;\
        int r= (((const type*)src)[i]>>shr)&maskr;\
\
        dst[i]= (((RY)*r + (GY)*g + (BY)*b + (33<<((S)-1)))>>(S));\
    }\
}

BGR2Y(uint32_t, bgr32ToY,16, 0, 0, 0x00FF, 0xFF00, 0x00FF, RY<< 8, GY   , BY<< 8, RGB2YUV_SHIFT+8)
BGR2Y(uint32_t,bgr321ToY,16,16, 0, 0xFF00, 0x00FF, 0xFF00, RY    , GY<<8, BY    , RGB2YUV_SHIFT+8)
BGR2Y(uint32_t, rgb32ToY, 0, 0,16, 0x00FF, 0xFF00, 0x00FF, RY<< 8, GY   , BY<< 8, RGB2YUV_SHIFT+8)
BGR2Y(uint32_t,rgb321ToY, 0,16,16, 0xFF00, 0x00FF, 0xFF00, RY    , GY<<8, BY    , RGB2YUV_SHIFT+8)
BGR2Y(uint16_t, bgr16ToY, 0, 0, 0, 0x001F, 0x07E0, 0xF800, RY<<11, GY<<5, BY    , RGB2YUV_SHIFT+8)
BGR2Y(uint16_t, bgr15ToY, 0, 0, 0, 0x001F, 0x03E0, 0x7C00, RY<<10, GY<<5, BY    , RGB2YUV_SHIFT+7)
BGR2Y(uint16_t, rgb16ToY, 0, 0, 0, 0xF800, 0x07E0, 0x001F, RY    , GY<<5, BY<<11, RGB2YUV_SHIFT+8)
BGR2Y(uint16_t, rgb15ToY, 0, 0, 0, 0x7C00, 0x03E0, 0x001F, RY    , GY<<5, BY<<10, RGB2YUV_SHIFT+7)

static void abgrToA_c(uint8_t *dst, const uint8_t *src, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        dst[i]= src[4*i];
    }
}

static void rgbaToA_c(uint8_t *dst, const uint8_t *src, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        dst[i]= src[4*i+3];
    }
}

#define BGR2UV(type, name, shr, shg, shb, shp, maskr, maskg, maskb, RU, GU, BU, RV, GV, BV, S) \
static void name ## _c(uint8_t *dstU, uint8_t *dstV, \
                       const uint8_t *src, const uint8_t *dummy, \
                       int width, uint32_t *unused)\
{\
    int i;\
    for (i=0; i<width; i++) {\
        int b= ((((const type*)src)[i]>>shp)&maskb)>>shb;\
        int g= ((((const type*)src)[i]>>shp)&maskg)>>shg;\
        int r= ((((const type*)src)[i]>>shp)&maskr)>>shr;\
\
        dstU[i]= ((RU)*r + (GU)*g + (BU)*b + (257<<((S)-1)))>>(S);\
        dstV[i]= ((RV)*r + (GV)*g + (BV)*b + (257<<((S)-1)))>>(S);\
    }\
}\
static void name ## _half_c(uint8_t *dstU, uint8_t *dstV, \
                            const uint8_t *src, const uint8_t *dummy, \
                            int width, uint32_t *unused)\
{\
    int i;\
    for (i=0; i<width; i++) {\
        int pix0= ((const type*)src)[2*i+0]>>shp;\
        int pix1= ((const type*)src)[2*i+1]>>shp;\
        int g= (pix0&~(maskr|maskb))+(pix1&~(maskr|maskb));\
        int b= ((pix0+pix1-g)&(maskb|(2*maskb)))>>shb;\
        int r= ((pix0+pix1-g)&(maskr|(2*maskr)))>>shr;\
        g&= maskg|(2*maskg);\
\
        g>>=shg;\
\
        dstU[i]= ((RU)*r + (GU)*g + (BU)*b + (257<<(S)))>>((S)+1);\
        dstV[i]= ((RV)*r + (GV)*g + (BV)*b + (257<<(S)))>>((S)+1);\
    }\
}

BGR2UV(uint32_t, bgr32ToUV,16, 0, 0, 0, 0xFF0000, 0xFF00,   0x00FF, RU<< 8, GU   , BU<< 8, RV<< 8, GV   , BV<< 8, RGB2YUV_SHIFT+8)
BGR2UV(uint32_t,bgr321ToUV,16, 0, 0, 8, 0xFF0000, 0xFF00,   0x00FF, RU<< 8, GU   , BU<< 8, RV<< 8, GV   , BV<< 8, RGB2YUV_SHIFT+8)
BGR2UV(uint32_t, rgb32ToUV, 0, 0,16, 0,   0x00FF, 0xFF00, 0xFF0000, RU<< 8, GU   , BU<< 8, RV<< 8, GV   , BV<< 8, RGB2YUV_SHIFT+8)
BGR2UV(uint32_t,rgb321ToUV, 0, 0,16, 8,   0x00FF, 0xFF00, 0xFF0000, RU<< 8, GU   , BU<< 8, RV<< 8, GV   , BV<< 8, RGB2YUV_SHIFT+8)
BGR2UV(uint16_t, bgr16ToUV, 0, 0, 0, 0,   0x001F, 0x07E0,   0xF800, RU<<11, GU<<5, BU    , RV<<11, GV<<5, BV    , RGB2YUV_SHIFT+8)
BGR2UV(uint16_t, bgr15ToUV, 0, 0, 0, 0,   0x001F, 0x03E0,   0x7C00, RU<<10, GU<<5, BU    , RV<<10, GV<<5, BV    , RGB2YUV_SHIFT+7)
BGR2UV(uint16_t, rgb16ToUV, 0, 0, 0, 0,   0xF800, 0x07E0,   0x001F, RU    , GU<<5, BU<<11, RV    , GV<<5, BV<<11, RGB2YUV_SHIFT+8)
BGR2UV(uint16_t, rgb15ToUV, 0, 0, 0, 0,   0x7C00, 0x03E0,   0x001F, RU    , GU<<5, BU<<10, RV    , GV<<5, BV<<10, RGB2YUV_SHIFT+7)

static void palToY_c(uint8_t *dst, const uint8_t *src, int width, uint32_t *pal)
{
    int i;
    for (i=0; i<width; i++) {
        int d= src[i];

        dst[i]= pal[d] & 0xFF;
    }
}

static void palToUV_c(uint8_t *dstU, uint8_t *dstV,
                      const uint8_t *src1, const uint8_t *src2,
                      int width, uint32_t *pal)
{
    int i;
    assert(src1 == src2);
    for (i=0; i<width; i++) {
        int p= pal[src1[i]];

        dstU[i]= p>>8;
        dstV[i]= p>>16;
    }
}

static void monowhite2Y_c(uint8_t *dst, const uint8_t *src,
                          int width, uint32_t *unused)
{
    int i, j;
    for (i=0; i<width/8; i++) {
        int d= ~src[i];
        for(j=0; j<8; j++)
            dst[8*i+j]= ((d>>(7-j))&1)*255;
    }
}

static void monoblack2Y_c(uint8_t *dst, const uint8_t *src,
                          int width, uint32_t *unused)
{
    int i, j;
    for (i=0; i<width/8; i++) {
        int d= src[i];
        for(j=0; j<8; j++)
            dst[8*i+j]= ((d>>(7-j))&1)*255;
    }
}

static void yuv2yuv1_c(SwsContext *c, const int16_t *lumSrc,
                       const int16_t *chrUSrc, const int16_t *chrVSrc,
                       const int16_t *alpSrc,
                       uint8_t *dest, uint8_t *uDest, uint8_t *vDest,
                       uint8_t *aDest, int dstW, int chrDstW)
{
    int i;
    for (i=0; i<dstW; i++) {
        int val= (lumSrc[i]+64)>>7;
        dest[i]= av_clip_uint8(val);
    }

    if (uDest)
        for (i=0; i<chrDstW; i++) {
            int u=(chrUSrc[i]+64)>>7;
            int v=(chrVSrc[i]+64)>>7;
            uDest[i]= av_clip_uint8(u);
            vDest[i]= av_clip_uint8(v);
        }

    if (CONFIG_SWSCALE_ALPHA && aDest)
        for (i=0; i<dstW; i++) {
            int val= (alpSrc[i]+64)>>7;
            aDest[i]= av_clip_uint8(val);
        }
}

/**
 * vertical bilinear scale YV12 to RGB
 */
static void yuv2packed2_c(SwsContext *c, const uint16_t *buf0,
                          const uint16_t *buf1, const uint16_t *ubuf0,
                          const uint16_t *ubuf1, const uint16_t *vbuf0,
                          const uint16_t *vbuf1, const uint16_t *abuf0,
                          const uint16_t *abuf1, uint8_t *dest, int dstW,
                          int yalpha, int uvalpha, int y)
{
    int  yalpha1=4095- yalpha;
    int uvalpha1=4095-uvalpha;
    int i;

    YSCALE_YUV_2_ANYRGB_C(YSCALE_YUV_2_RGB2_C, YSCALE_YUV_2_PACKED2_C(void,0), YSCALE_YUV_2_GRAY16_2_C, YSCALE_YUV_2_MONO2_C)
}

/**
 * YV12 to RGB without scaling or interpolating
 */
static void yuv2packed1_c(SwsContext *c, const uint16_t *buf0,
                          const uint16_t *ubuf0, const uint16_t *ubuf1,
                          const uint16_t *vbuf0, const uint16_t *vbuf1,
                          const uint16_t *abuf0, uint8_t *dest, int dstW,
                          int uvalpha, enum PixelFormat dstFormat,
                          int flags, int y)
{
    const int yalpha1=0;
    int i;

    const uint16_t *buf1= buf0; //FIXME needed for RGB1/BGR1
    const int yalpha= 4096; //FIXME ...

    if (uvalpha < 2048) {
        YSCALE_YUV_2_ANYRGB_C(YSCALE_YUV_2_RGB1_C, YSCALE_YUV_2_PACKED1_C(void,0), YSCALE_YUV_2_GRAY16_1_C, YSCALE_YUV_2_MONO2_C)
    } else {
        YSCALE_YUV_2_ANYRGB_C(YSCALE_YUV_2_RGB1B_C, YSCALE_YUV_2_PACKED1B_C(void,0), YSCALE_YUV_2_GRAY16_1_C, YSCALE_YUV_2_MONO2_C)
    }
}

//FIXME yuy2* can read up to 7 samples too much

static void yuy2ToY_c(uint8_t *dst, const uint8_t *src, int width,
                      uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++)
        dst[i]= src[2*i];
}

static void yuy2ToUV_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                       const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        dstU[i]= src1[4*i + 1];
        dstV[i]= src1[4*i + 3];
    }
    assert(src1 == src2);
}

static void LEToUV_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                     const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        dstU[i]= src1[2*i + 1];
        dstV[i]= src2[2*i + 1];
    }
}

/* This is almost identical to the previous, end exists only because
 * yuy2ToY/UV)(dst, src+1, ...) would have 100% unaligned accesses. */
static void uyvyToY_c(uint8_t *dst, const uint8_t *src, int width,
                      uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++)
        dst[i]= src[2*i+1];
}

static void uyvyToUV_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                       const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        dstU[i]= src1[4*i + 0];
        dstV[i]= src1[4*i + 2];
    }
    assert(src1 == src2);
}

static void BEToUV_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                     const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        dstU[i]= src1[2*i];
        dstV[i]= src2[2*i];
    }
}

static av_always_inline void nvXXtoUV_c(uint8_t *dst1, uint8_t *dst2,
                                        const uint8_t *src, int width)
{
    int i;
    for (i = 0; i < width; i++) {
        dst1[i] = src[2*i+0];
        dst2[i] = src[2*i+1];
    }
}

static void nv12ToUV_c(uint8_t *dstU, uint8_t *dstV,
                       const uint8_t *src1, const uint8_t *src2,
                       int width, uint32_t *unused)
{
    nvXXtoUV_c(dstU, dstV, src1, width);
}

static void nv21ToUV_c(uint8_t *dstU, uint8_t *dstV,
                       const uint8_t *src1, const uint8_t *src2,
                       int width, uint32_t *unused)
{
    nvXXtoUV_c(dstV, dstU, src1, width);
}

// FIXME Maybe dither instead.
#define YUV_NBPS(depth, endianness, rfunc) \
static void endianness ## depth ## ToUV_c(uint8_t *dstU, uint8_t *dstV, \
                                          const uint8_t *_srcU, const uint8_t *_srcV, \
                                          int width, uint32_t *unused) \
{ \
    int i; \
    const uint16_t *srcU = (const uint16_t*)_srcU; \
    const uint16_t *srcV = (const uint16_t*)_srcV; \
    for (i = 0; i < width; i++) { \
        dstU[i] = rfunc(&srcU[i])>>(depth-8); \
        dstV[i] = rfunc(&srcV[i])>>(depth-8); \
    } \
} \
\
static void endianness ## depth ## ToY_c(uint8_t *dstY, const uint8_t *_srcY, \
                                         int width, uint32_t *unused) \
{ \
    int i; \
    const uint16_t *srcY = (const uint16_t*)_srcY; \
    for (i = 0; i < width; i++) \
        dstY[i] = rfunc(&srcY[i])>>(depth-8); \
} \

YUV_NBPS( 9, LE, AV_RL16)
YUV_NBPS( 9, BE, AV_RB16)
YUV_NBPS(10, LE, AV_RL16)
YUV_NBPS(10, BE, AV_RB16)

static void bgr24ToY_c(uint8_t *dst, const uint8_t *src,
                       int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        int b= src[i*3+0];
        int g= src[i*3+1];
        int r= src[i*3+2];

        dst[i]= ((RY*r + GY*g + BY*b + (33<<(RGB2YUV_SHIFT-1)))>>RGB2YUV_SHIFT);
    }
}

static void bgr24ToUV_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                        const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        int b= src1[3*i + 0];
        int g= src1[3*i + 1];
        int r= src1[3*i + 2];

        dstU[i]= (RU*r + GU*g + BU*b + (257<<(RGB2YUV_SHIFT-1)))>>RGB2YUV_SHIFT;
        dstV[i]= (RV*r + GV*g + BV*b + (257<<(RGB2YUV_SHIFT-1)))>>RGB2YUV_SHIFT;
    }
    assert(src1 == src2);
}

static void bgr24ToUV_half_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                             const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        int b= src1[6*i + 0] + src1[6*i + 3];
        int g= src1[6*i + 1] + src1[6*i + 4];
        int r= src1[6*i + 2] + src1[6*i + 5];

        dstU[i]= (RU*r + GU*g + BU*b + (257<<RGB2YUV_SHIFT))>>(RGB2YUV_SHIFT+1);
        dstV[i]= (RV*r + GV*g + BV*b + (257<<RGB2YUV_SHIFT))>>(RGB2YUV_SHIFT+1);
    }
    assert(src1 == src2);
}

static void rgb24ToY_c(uint8_t *dst, const uint8_t *src, int width,
                       uint32_t *unused)
{
    int i;
    for (i=0; i<width; i++) {
        int r= src[i*3+0];
        int g= src[i*3+1];
        int b= src[i*3+2];

        dst[i]= ((RY*r + GY*g + BY*b + (33<<(RGB2YUV_SHIFT-1)))>>RGB2YUV_SHIFT);
    }
}

static void rgb24ToUV_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                        const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    assert(src1==src2);
    for (i=0; i<width; i++) {
        int r= src1[3*i + 0];
        int g= src1[3*i + 1];
        int b= src1[3*i + 2];

        dstU[i]= (RU*r + GU*g + BU*b + (257<<(RGB2YUV_SHIFT-1)))>>RGB2YUV_SHIFT;
        dstV[i]= (RV*r + GV*g + BV*b + (257<<(RGB2YUV_SHIFT-1)))>>RGB2YUV_SHIFT;
    }
}

static void rgb24ToUV_half_c(uint8_t *dstU, uint8_t *dstV, const uint8_t *src1,
                             const uint8_t *src2, int width, uint32_t *unused)
{
    int i;
    assert(src1==src2);
    for (i=0; i<width; i++) {
        int r= src1[6*i + 0] + src1[6*i + 3];
        int g= src1[6*i + 1] + src1[6*i + 4];
        int b= src1[6*i + 2] + src1[6*i + 5];

        dstU[i]= (RU*r + GU*g + BU*b + (257<<RGB2YUV_SHIFT))>>(RGB2YUV_SHIFT+1);
        dstV[i]= (RV*r + GV*g + BV*b + (257<<RGB2YUV_SHIFT))>>(RGB2YUV_SHIFT+1);
    }
}


// bilinear / bicubic scaling
static void hScale_c(int16_t *dst, int dstW, const uint8_t *src,
                     int srcW, int xInc,
                     const int16_t *filter, const int16_t *filterPos,
                     int filterSize)
{
    int i;
    for (i=0; i<dstW; i++) {
        int j;
        int srcPos= filterPos[i];
        int val=0;
        for (j=0; j<filterSize; j++) {
            val += ((int)src[srcPos + j])*filter[filterSize*i + j];
        }
        //filter += hFilterSize;
        dst[i] = FFMIN(val>>7, (1<<15)-1); // the cubic equation does overflow ...
        //dst[i] = val>>7;
    }
}

//FIXME all pal and rgb srcFormats could do this convertion as well
//FIXME all scalers more complex than bilinear could do half of this transform
static void chrRangeToJpeg_c(uint16_t *dstU, uint16_t *dstV, int width)
{
    int i;
    for (i = 0; i < width; i++) {
        dstU[i] = (FFMIN(dstU[i],30775)*4663 - 9289992)>>12; //-264
        dstV[i] = (FFMIN(dstV[i],30775)*4663 - 9289992)>>12; //-264
    }
}
static void chrRangeFromJpeg_c(uint16_t *dstU, uint16_t *dstV, int width)
{
    int i;
    for (i = 0; i < width; i++) {
        dstU[i] = (dstU[i]*1799 + 4081085)>>11; //1469
        dstV[i] = (dstV[i]*1799 + 4081085)>>11; //1469
    }
}
static void lumRangeToJpeg_c(uint16_t *dst, int width)
{
    int i;
    for (i = 0; i < width; i++)
        dst[i] = (FFMIN(dst[i],30189)*19077 - 39057361)>>14;
}
static void lumRangeFromJpeg_c(uint16_t *dst, int width)
{
    int i;
    for (i = 0; i < width; i++)
        dst[i] = (dst[i]*14071 + 33561947)>>14;
}

static void hyscale_fast_c(SwsContext *c, int16_t *dst, int dstWidth,
                           const uint8_t *src, int srcW, int xInc)
{
    int i;
    unsigned int xpos=0;
    for (i=0;i<dstWidth;i++) {
        register unsigned int xx=xpos>>16;
        register unsigned int xalpha=(xpos&0xFFFF)>>9;
        dst[i]= (src[xx]<<7) + (src[xx+1] - src[xx])*xalpha;
        xpos+=xInc;
    }
}

// *** horizontal scale Y line to temp buffer
static inline void hyscale(SwsContext *c, uint16_t *dst, int dstWidth,
                           const uint8_t *src, int srcW, int xInc,
                           const int16_t *hLumFilter,
                           const int16_t *hLumFilterPos, int hLumFilterSize,
                           uint8_t *formatConvBuffer,
                           uint32_t *pal, int isAlpha)
{
    void (*toYV12)(uint8_t *, const uint8_t *, int, uint32_t *) = isAlpha ? c->alpToYV12 : c->lumToYV12;
    void (*convertRange)(uint16_t *, int) = isAlpha ? NULL : c->lumConvertRange;

    if (toYV12) {
        toYV12(formatConvBuffer, src, srcW, pal);
        src= formatConvBuffer;
    }

    if (!c->hyscale_fast) {
        c->hScale(dst, dstWidth, src, srcW, xInc, hLumFilter, hLumFilterPos, hLumFilterSize);
    } else { // fast bilinear upscale / crap downscale
        c->hyscale_fast(c, dst, dstWidth, src, srcW, xInc);
    }

    if (convertRange)
        convertRange(dst, dstWidth);
}

static void hcscale_fast_c(SwsContext *c, int16_t *dst1, int16_t *dst2,
                           int dstWidth, const uint8_t *src1,
                           const uint8_t *src2, int srcW, int xInc)
{
    int i;
    unsigned int xpos=0;
    for (i=0;i<dstWidth;i++) {
        register unsigned int xx=xpos>>16;
        register unsigned int xalpha=(xpos&0xFFFF)>>9;
        dst1[i]=(src1[xx]*(xalpha^127)+src1[xx+1]*xalpha);
        dst2[i]=(src2[xx]*(xalpha^127)+src2[xx+1]*xalpha);
        xpos+=xInc;
    }
}

static inline void hcscale(SwsContext *c, uint16_t *dst1, uint16_t *dst2, int dstWidth,
                           const uint8_t *src1, const uint8_t *src2,
                           int srcW, int xInc, const int16_t *hChrFilter,
                           const int16_t *hChrFilterPos, int hChrFilterSize,
                           uint8_t *formatConvBuffer, uint32_t *pal)
{
    if (c->chrToYV12) {
        uint8_t *buf2 = formatConvBuffer + FFALIGN(srcW, 16);
        c->chrToYV12(formatConvBuffer, buf2, src1, src2, srcW, pal);
        src1= formatConvBuffer;
        src2= buf2;
    }

    if (!c->hcscale_fast) {
        c->hScale(dst1, dstWidth, src1, srcW, xInc, hChrFilter, hChrFilterPos, hChrFilterSize);
        c->hScale(dst2, dstWidth, src2, srcW, xInc, hChrFilter, hChrFilterPos, hChrFilterSize);
    } else { // fast bilinear upscale / crap downscale
        c->hcscale_fast(c, dst1, dst2, dstWidth, src1, src2, srcW, xInc);
    }

    if (c->chrConvertRange)
        c->chrConvertRange(dst1, dst2, dstWidth);
}

#define DEBUG_SWSCALE_BUFFERS 0
#define DEBUG_BUFFERS(...) if (DEBUG_SWSCALE_BUFFERS) av_log(c, AV_LOG_DEBUG, __VA_ARGS__)

static int swScale(SwsContext *c, const uint8_t* src[],
                   int srcStride[], int srcSliceY,
                   int srcSliceH, uint8_t* dst[], int dstStride[])
{
    /* load a few things into local vars to make the code more readable? and faster */
    const int srcW= c->srcW;
    const int dstW= c->dstW;
    const int dstH= c->dstH;
    const int chrDstW= c->chrDstW;
    const int chrSrcW= c->chrSrcW;
    const int lumXInc= c->lumXInc;
    const int chrXInc= c->chrXInc;
    const enum PixelFormat dstFormat= c->dstFormat;
    const int flags= c->flags;
    int16_t *vLumFilterPos= c->vLumFilterPos;
    int16_t *vChrFilterPos= c->vChrFilterPos;
    int16_t *hLumFilterPos= c->hLumFilterPos;
    int16_t *hChrFilterPos= c->hChrFilterPos;
    int16_t *vLumFilter= c->vLumFilter;
    int16_t *vChrFilter= c->vChrFilter;
    int16_t *hLumFilter= c->hLumFilter;
    int16_t *hChrFilter= c->hChrFilter;
    int32_t *lumMmxFilter= c->lumMmxFilter;
    int32_t *chrMmxFilter= c->chrMmxFilter;
    int32_t av_unused *alpMmxFilter= c->alpMmxFilter;
    const int vLumFilterSize= c->vLumFilterSize;
    const int vChrFilterSize= c->vChrFilterSize;
    const int hLumFilterSize= c->hLumFilterSize;
    const int hChrFilterSize= c->hChrFilterSize;
    int16_t **lumPixBuf= c->lumPixBuf;
    int16_t **chrUPixBuf= c->chrUPixBuf;
    int16_t **chrVPixBuf= c->chrVPixBuf;
    int16_t **alpPixBuf= c->alpPixBuf;
    const int vLumBufSize= c->vLumBufSize;
    const int vChrBufSize= c->vChrBufSize;
    uint8_t *formatConvBuffer= c->formatConvBuffer;
    const int chrSrcSliceY= srcSliceY >> c->chrSrcVSubSample;
    const int chrSrcSliceH= -((-srcSliceH) >> c->chrSrcVSubSample);
    int lastDstY;
    uint32_t *pal=c->pal_yuv;

    /* vars which will change and which we need to store back in the context */
    int dstY= c->dstY;
    int lumBufIndex= c->lumBufIndex;
    int chrBufIndex= c->chrBufIndex;
    int lastInLumBuf= c->lastInLumBuf;
    int lastInChrBuf= c->lastInChrBuf;

    if (isPacked(c->srcFormat)) {
        src[0]=
        src[1]=
        src[2]=
        src[3]= src[0];
        srcStride[0]=
        srcStride[1]=
        srcStride[2]=
        srcStride[3]= srcStride[0];
    }
    srcStride[1]<<= c->vChrDrop;
    srcStride[2]<<= c->vChrDrop;

    DEBUG_BUFFERS("swScale() %p[%d] %p[%d] %p[%d] %p[%d] -> %p[%d] %p[%d] %p[%d] %p[%d]\n",
                  src[0], srcStride[0], src[1], srcStride[1], src[2], srcStride[2], src[3], srcStride[3],
                  dst[0], dstStride[0], dst[1], dstStride[1], dst[2], dstStride[2], dst[3], dstStride[3]);
    DEBUG_BUFFERS("srcSliceY: %d srcSliceH: %d dstY: %d dstH: %d\n",
                   srcSliceY,    srcSliceH,    dstY,    dstH);
    DEBUG_BUFFERS("vLumFilterSize: %d vLumBufSize: %d vChrFilterSize: %d vChrBufSize: %d\n",
                   vLumFilterSize,    vLumBufSize,    vChrFilterSize,    vChrBufSize);

    if (dstStride[0]%8 !=0 || dstStride[1]%8 !=0 || dstStride[2]%8 !=0 || dstStride[3]%8 != 0) {
        static int warnedAlready=0; //FIXME move this into the context perhaps
        if (flags & SWS_PRINT_INFO && !warnedAlready) {
            av_log(c, AV_LOG_WARNING, "Warning: dstStride is not aligned!\n"
                   "         ->cannot do aligned memory accesses anymore\n");
            warnedAlready=1;
        }
    }

    /* Note the user might start scaling the picture in the middle so this
       will not get executed. This is not really intended but works
       currently, so people might do it. */
    if (srcSliceY ==0) {
        lumBufIndex=-1;
        chrBufIndex=-1;
        dstY=0;
        lastInLumBuf= -1;
        lastInChrBuf= -1;
    }

    lastDstY= dstY;

    for (;dstY < dstH; dstY++) {
        unsigned char *dest =dst[0]+dstStride[0]*dstY;
        const int chrDstY= dstY>>c->chrDstVSubSample;
        unsigned char *uDest=dst[1]+dstStride[1]*chrDstY;
        unsigned char *vDest=dst[2]+dstStride[2]*chrDstY;
        unsigned char *aDest=(CONFIG_SWSCALE_ALPHA && alpPixBuf) ? dst[3]+dstStride[3]*dstY : NULL;

        const int firstLumSrcY= vLumFilterPos[dstY]; //First line needed as input
        const int firstLumSrcY2= vLumFilterPos[FFMIN(dstY | ((1<<c->chrDstVSubSample) - 1), dstH-1)];
        const int firstChrSrcY= vChrFilterPos[chrDstY]; //First line needed as input
        int lastLumSrcY= firstLumSrcY + vLumFilterSize -1; // Last line needed as input
        int lastLumSrcY2=firstLumSrcY2+ vLumFilterSize -1; // Last line needed as input
        int lastChrSrcY= firstChrSrcY + vChrFilterSize -1; // Last line needed as input
        int enough_lines;

        //handle holes (FAST_BILINEAR & weird filters)
        if (firstLumSrcY > lastInLumBuf) lastInLumBuf= firstLumSrcY-1;
        if (firstChrSrcY > lastInChrBuf) lastInChrBuf= firstChrSrcY-1;
        assert(firstLumSrcY >= lastInLumBuf - vLumBufSize + 1);
        assert(firstChrSrcY >= lastInChrBuf - vChrBufSize + 1);

        DEBUG_BUFFERS("dstY: %d\n", dstY);
        DEBUG_BUFFERS("\tfirstLumSrcY: %d lastLumSrcY: %d lastInLumBuf: %d\n",
                         firstLumSrcY,    lastLumSrcY,    lastInLumBuf);
        DEBUG_BUFFERS("\tfirstChrSrcY: %d lastChrSrcY: %d lastInChrBuf: %d\n",
                         firstChrSrcY,    lastChrSrcY,    lastInChrBuf);

        // Do we have enough lines in this slice to output the dstY line
        enough_lines = lastLumSrcY2 < srcSliceY + srcSliceH && lastChrSrcY < -((-srcSliceY - srcSliceH)>>c->chrSrcVSubSample);

        if (!enough_lines) {
            lastLumSrcY = srcSliceY + srcSliceH - 1;
            lastChrSrcY = chrSrcSliceY + chrSrcSliceH - 1;
            DEBUG_BUFFERS("buffering slice: lastLumSrcY %d lastChrSrcY %d\n",
                                            lastLumSrcY, lastChrSrcY);
        }

        //Do horizontal scaling
        while(lastInLumBuf < lastLumSrcY) {
            const uint8_t *src1= src[0]+(lastInLumBuf + 1 - srcSliceY)*srcStride[0];
            const uint8_t *src2= src[3]+(lastInLumBuf + 1 - srcSliceY)*srcStride[3];
            lumBufIndex++;
            assert(lumBufIndex < 2*vLumBufSize);
            assert(lastInLumBuf + 1 - srcSliceY < srcSliceH);
            assert(lastInLumBuf + 1 - srcSliceY >= 0);
            hyscale(c, lumPixBuf[ lumBufIndex ], dstW, src1, srcW, lumXInc,
                    hLumFilter, hLumFilterPos, hLumFilterSize,
                    formatConvBuffer,
                    pal, 0);
            if (CONFIG_SWSCALE_ALPHA && alpPixBuf)
                hyscale(c, alpPixBuf[ lumBufIndex ], dstW, src2, srcW,
                        lumXInc, hLumFilter, hLumFilterPos, hLumFilterSize,
                        formatConvBuffer,
                        pal, 1);
            lastInLumBuf++;
            DEBUG_BUFFERS("\t\tlumBufIndex %d: lastInLumBuf: %d\n",
                               lumBufIndex,    lastInLumBuf);
        }
        while(lastInChrBuf < lastChrSrcY) {
            const uint8_t *src1= src[1]+(lastInChrBuf + 1 - chrSrcSliceY)*srcStride[1];
            const uint8_t *src2= src[2]+(lastInChrBuf + 1 - chrSrcSliceY)*srcStride[2];
            chrBufIndex++;
            assert(chrBufIndex < 2*vChrBufSize);
            assert(lastInChrBuf + 1 - chrSrcSliceY < (chrSrcSliceH));
            assert(lastInChrBuf + 1 - chrSrcSliceY >= 0);
            //FIXME replace parameters through context struct (some at least)

            if (c->needs_hcscale)
                hcscale(c, chrUPixBuf[chrBufIndex], chrVPixBuf[chrBufIndex],
                          chrDstW, src1, src2, chrSrcW, chrXInc,
                          hChrFilter, hChrFilterPos, hChrFilterSize,
                          formatConvBuffer, pal);
            lastInChrBuf++;
            DEBUG_BUFFERS("\t\tchrBufIndex %d: lastInChrBuf: %d\n",
                               chrBufIndex,    lastInChrBuf);
        }
        //wrap buf index around to stay inside the ring buffer
        if (lumBufIndex >= vLumBufSize) lumBufIndex-= vLumBufSize;
        if (chrBufIndex >= vChrBufSize) chrBufIndex-= vChrBufSize;
        if (!enough_lines)
            break; //we can't output a dstY line so let's try with the next slice

#if HAVE_MMX
        updateMMXDitherTables(c, dstY, lumBufIndex, chrBufIndex, lastInLumBuf, lastInChrBuf);
#endif
        if (dstY < dstH-2) {
            const int16_t **lumSrcPtr= (const int16_t **) lumPixBuf + lumBufIndex + firstLumSrcY - lastInLumBuf + vLumBufSize;
            const int16_t **chrUSrcPtr= (const int16_t **) chrUPixBuf + chrBufIndex + firstChrSrcY - lastInChrBuf + vChrBufSize;
            const int16_t **chrVSrcPtr= (const int16_t **) chrVPixBuf + chrBufIndex + firstChrSrcY - lastInChrBuf + vChrBufSize;
            const int16_t **alpSrcPtr= (CONFIG_SWSCALE_ALPHA && alpPixBuf) ? (const int16_t **) alpPixBuf + lumBufIndex + firstLumSrcY - lastInLumBuf + vLumBufSize : NULL;
            if (isPlanarYUV(dstFormat) || dstFormat==PIX_FMT_GRAY8) { //YV12 like
                const int chrSkipMask= (1<<c->chrDstVSubSample)-1;
                if ((dstY&chrSkipMask) || isGray(dstFormat)) uDest=vDest= NULL; //FIXME split functions in lumi / chromi
                if (c->yuv2yuv1 && vLumFilterSize == 1 && vChrFilterSize == 1) { // unscaled YV12
                    const int16_t *lumBuf = lumSrcPtr[0];
                    const int16_t *chrUBuf= chrUSrcPtr[0];
                    const int16_t *chrVBuf= chrVSrcPtr[0];
                    const int16_t *alpBuf= (CONFIG_SWSCALE_ALPHA && alpPixBuf) ? alpSrcPtr[0] : NULL;
                    c->yuv2yuv1(c, lumBuf, chrUBuf, chrVBuf, alpBuf, dest,
                                uDest, vDest, aDest, dstW, chrDstW);
                } else { //General YV12
                    c->yuv2yuvX(c,
                                vLumFilter+dstY*vLumFilterSize   , lumSrcPtr, vLumFilterSize,
                                vChrFilter+chrDstY*vChrFilterSize, chrUSrcPtr,
                                chrVSrcPtr, vChrFilterSize,
                                alpSrcPtr, dest, uDest, vDest, aDest, dstW, chrDstW);
                }
            } else {
                assert(lumSrcPtr  + vLumFilterSize - 1 < lumPixBuf  + vLumBufSize*2);
                assert(chrUSrcPtr + vChrFilterSize - 1 < chrUPixBuf + vChrBufSize*2);
                if (c->yuv2packed1 && vLumFilterSize == 1 && vChrFilterSize == 2) { //unscaled RGB
                    int chrAlpha= vChrFilter[2*dstY+1];
                    c->yuv2packed1(c, *lumSrcPtr, *chrUSrcPtr, *(chrUSrcPtr+1),
                                   *chrVSrcPtr, *(chrVSrcPtr+1),
                                   alpPixBuf ? *alpSrcPtr : NULL,
                                   dest, dstW, chrAlpha, dstFormat, flags, dstY);
                } else if (c->yuv2packed2 && vLumFilterSize == 2 && vChrFilterSize == 2) { //bilinear upscale RGB
                    int lumAlpha= vLumFilter[2*dstY+1];
                    int chrAlpha= vChrFilter[2*dstY+1];
                    lumMmxFilter[2]=
                    lumMmxFilter[3]= vLumFilter[2*dstY   ]*0x10001;
                    chrMmxFilter[2]=
                    chrMmxFilter[3]= vChrFilter[2*chrDstY]*0x10001;
                    c->yuv2packed2(c, *lumSrcPtr, *(lumSrcPtr+1), *chrUSrcPtr, *(chrUSrcPtr+1),
                                   *chrVSrcPtr, *(chrVSrcPtr+1),
                                   alpPixBuf ? *alpSrcPtr : NULL, alpPixBuf ? *(alpSrcPtr+1) : NULL,
                                   dest, dstW, lumAlpha, chrAlpha, dstY);
                } else { //general RGB
                    c->yuv2packedX(c,
                                   vLumFilter+dstY*vLumFilterSize, lumSrcPtr, vLumFilterSize,
                                   vChrFilter+dstY*vChrFilterSize, chrUSrcPtr, chrVSrcPtr, vChrFilterSize,
                                   alpSrcPtr, dest, dstW, dstY);
                }
            }
        } else { // hmm looks like we can't use MMX here without overwriting this array's tail
            const int16_t **lumSrcPtr= (const int16_t **)lumPixBuf + lumBufIndex + firstLumSrcY - lastInLumBuf + vLumBufSize;
            const int16_t **chrUSrcPtr= (const int16_t **)chrUPixBuf + chrBufIndex + firstChrSrcY - lastInChrBuf + vChrBufSize;
            const int16_t **chrVSrcPtr= (const int16_t **)chrVPixBuf + chrBufIndex + firstChrSrcY - lastInChrBuf + vChrBufSize;
            const int16_t **alpSrcPtr= (CONFIG_SWSCALE_ALPHA && alpPixBuf) ? (const int16_t **)alpPixBuf + lumBufIndex + firstLumSrcY - lastInLumBuf + vLumBufSize : NULL;
            if (dstFormat == PIX_FMT_NV12 || dstFormat == PIX_FMT_NV21) {
                const int chrSkipMask= (1<<c->chrDstVSubSample)-1;
                if (dstY&chrSkipMask) uDest= NULL; //FIXME split functions in lumi / chromi
                yuv2nv12X_c(c, vLumFilter+dstY*vLumFilterSize,
                            lumSrcPtr, vLumFilterSize,
                            vChrFilter+chrDstY*vChrFilterSize,
                            chrUSrcPtr, chrVSrcPtr, vChrFilterSize, NULL,
                            dest, uDest, NULL, NULL, dstW, chrDstW);
            } else if (isPlanarYUV(dstFormat) || dstFormat==PIX_FMT_GRAY8) { //YV12
                const int chrSkipMask= (1<<c->chrDstVSubSample)-1;
                if ((dstY&chrSkipMask) || isGray(dstFormat)) uDest=vDest= NULL; //FIXME split functions in lumi / chromi
                if (is16BPS(dstFormat) || is9_OR_10BPS(dstFormat)) {
                    yuv2yuvX16_c(c, vLumFilter+dstY*vLumFilterSize   , lumSrcPtr, vLumFilterSize,
                                 vChrFilter+chrDstY*vChrFilterSize, chrUSrcPtr, chrVSrcPtr, vChrFilterSize,
                                 alpSrcPtr, dest, uDest, vDest, aDest, dstW, chrDstW,
                                 dstFormat);
                } else {
                    yuv2yuvX_c(c, vLumFilter+dstY*vLumFilterSize,
                               lumSrcPtr, vLumFilterSize,
                               vChrFilter+chrDstY*vChrFilterSize,
                               chrUSrcPtr, chrVSrcPtr, vChrFilterSize,
                               alpSrcPtr, dest, uDest, vDest, aDest,
                               dstW, chrDstW);
                }
            } else {
                assert(lumSrcPtr + vLumFilterSize - 1 < lumPixBuf + vLumBufSize*2);
                assert(chrUSrcPtr + vChrFilterSize - 1 < chrUPixBuf + vChrBufSize*2);
                if(flags & SWS_FULL_CHR_H_INT) {
                    yuv2rgbX_c_full(c,
                                    vLumFilter+dstY*vLumFilterSize, lumSrcPtr, vLumFilterSize,
                                    vChrFilter+dstY*vChrFilterSize, chrUSrcPtr, chrVSrcPtr, vChrFilterSize,
                                    alpSrcPtr, dest, dstW, dstY);
                } else {
                    yuv2packedX_c(c,
                                  vLumFilter+dstY*vLumFilterSize, lumSrcPtr, vLumFilterSize,
                                  vChrFilter+dstY*vChrFilterSize, chrUSrcPtr, chrVSrcPtr, vChrFilterSize,
                                  alpSrcPtr, dest, dstW, dstY);
                }
            }
        }
    }

    if ((dstFormat == PIX_FMT_YUVA420P) && !alpPixBuf)
        fillPlane(dst[3], dstStride[3], dstW, dstY-lastDstY, lastDstY, 255);

#if HAVE_MMX2
    if (av_get_cpu_flags() & AV_CPU_FLAG_MMX2)
        __asm__ volatile("sfence":::"memory");
#endif
    emms_c();

    /* store changed local vars back in the context */
    c->dstY= dstY;
    c->lumBufIndex= lumBufIndex;
    c->chrBufIndex= chrBufIndex;
    c->lastInLumBuf= lastInLumBuf;
    c->lastInChrBuf= lastInChrBuf;

    return dstY - lastDstY;
}

static void sws_init_swScale_c(SwsContext *c)
{
    enum PixelFormat srcFormat = c->srcFormat,
                     dstFormat = c->dstFormat;

    if (dstFormat == PIX_FMT_NV12 || dstFormat == PIX_FMT_NV21) {
        c->yuv2yuvX     = yuv2nv12X_c;
    } else if (is16BPS(dstFormat)) {
        c->yuv2yuvX     = isBE(dstFormat) ? yuv2yuvX16BE_c  : yuv2yuvX16LE_c;
    } else if (is9_OR_10BPS(dstFormat)) {
        if (dstFormat == PIX_FMT_YUV420P9BE || dstFormat == PIX_FMT_YUV420P9LE) {
            c->yuv2yuvX = isBE(dstFormat) ? yuv2yuvX9BE_c :  yuv2yuvX9LE_c;
        } else {
            c->yuv2yuvX = isBE(dstFormat) ? yuv2yuvX10BE_c : yuv2yuvX10LE_c;
        }
    } else {
        c->yuv2yuv1     = yuv2yuv1_c;
        c->yuv2yuvX     = yuv2yuvX_c;
    }
    if(c->flags & SWS_FULL_CHR_H_INT) {
        c->yuv2packedX = yuv2rgbX_c_full;
    } else {
        c->yuv2packed1  = yuv2packed1_c;
        c->yuv2packed2  = yuv2packed2_c;
        c->yuv2packedX  = yuv2packedX_c;
    }

    c->hScale       = hScale_c;

    if (c->flags & SWS_FAST_BILINEAR) {
        c->hyscale_fast = hyscale_fast_c;
        c->hcscale_fast = hcscale_fast_c;
    }

    c->chrToYV12 = NULL;
    switch(srcFormat) {
        case PIX_FMT_YUYV422  : c->chrToYV12 = yuy2ToUV_c; break;
        case PIX_FMT_UYVY422  : c->chrToYV12 = uyvyToUV_c; break;
        case PIX_FMT_NV12     : c->chrToYV12 = nv12ToUV_c; break;
        case PIX_FMT_NV21     : c->chrToYV12 = nv21ToUV_c; break;
        case PIX_FMT_RGB8     :
        case PIX_FMT_BGR8     :
        case PIX_FMT_PAL8     :
        case PIX_FMT_BGR4_BYTE:
        case PIX_FMT_RGB4_BYTE: c->chrToYV12 = palToUV_c; break;
        case PIX_FMT_YUV420P9BE: c->chrToYV12 = BE9ToUV_c; break;
        case PIX_FMT_YUV420P9LE: c->chrToYV12 = LE9ToUV_c; break;
        case PIX_FMT_YUV420P10BE: c->chrToYV12 = BE10ToUV_c; break;
        case PIX_FMT_YUV420P10LE: c->chrToYV12 = LE10ToUV_c; break;
        case PIX_FMT_YUV420P16BE:
        case PIX_FMT_YUV422P16BE:
        case PIX_FMT_YUV444P16BE: c->chrToYV12 = BEToUV_c; break;
        case PIX_FMT_YUV420P16LE:
        case PIX_FMT_YUV422P16LE:
        case PIX_FMT_YUV444P16LE: c->chrToYV12 = LEToUV_c; break;
    }
    if (c->chrSrcHSubSample) {
        switch(srcFormat) {
        case PIX_FMT_RGB48BE: c->chrToYV12 = rgb48BEToUV_half_c; break;
        case PIX_FMT_RGB48LE: c->chrToYV12 = rgb48LEToUV_half_c; break;
        case PIX_FMT_BGR48BE: c->chrToYV12 = bgr48BEToUV_half_c; break;
        case PIX_FMT_BGR48LE: c->chrToYV12 = bgr48LEToUV_half_c; break;
        case PIX_FMT_RGB32  : c->chrToYV12 = bgr32ToUV_half_c;  break;
        case PIX_FMT_RGB32_1: c->chrToYV12 = bgr321ToUV_half_c; break;
        case PIX_FMT_BGR24  : c->chrToYV12 = bgr24ToUV_half_c; break;
        case PIX_FMT_BGR565 : c->chrToYV12 = bgr16ToUV_half_c; break;
        case PIX_FMT_BGR555 : c->chrToYV12 = bgr15ToUV_half_c; break;
        case PIX_FMT_BGR32  : c->chrToYV12 = rgb32ToUV_half_c;  break;
        case PIX_FMT_BGR32_1: c->chrToYV12 = rgb321ToUV_half_c; break;
        case PIX_FMT_RGB24  : c->chrToYV12 = rgb24ToUV_half_c; break;
        case PIX_FMT_RGB565 : c->chrToYV12 = rgb16ToUV_half_c; break;
        case PIX_FMT_RGB555 : c->chrToYV12 = rgb15ToUV_half_c; break;
        }
    } else {
        switch(srcFormat) {
        case PIX_FMT_RGB48BE: c->chrToYV12 = rgb48BEToUV_c; break;
        case PIX_FMT_RGB48LE: c->chrToYV12 = rgb48LEToUV_c; break;
        case PIX_FMT_BGR48BE: c->chrToYV12 = bgr48BEToUV_c; break;
        case PIX_FMT_BGR48LE: c->chrToYV12 = bgr48LEToUV_c; break;
        case PIX_FMT_RGB32  : c->chrToYV12 = bgr32ToUV_c;  break;
        case PIX_FMT_RGB32_1: c->chrToYV12 = bgr321ToUV_c; break;
        case PIX_FMT_BGR24  : c->chrToYV12 = bgr24ToUV_c; break;
        case PIX_FMT_BGR565 : c->chrToYV12 = bgr16ToUV_c; break;
        case PIX_FMT_BGR555 : c->chrToYV12 = bgr15ToUV_c; break;
        case PIX_FMT_BGR32  : c->chrToYV12 = rgb32ToUV_c;  break;
        case PIX_FMT_BGR32_1: c->chrToYV12 = rgb321ToUV_c; break;
        case PIX_FMT_RGB24  : c->chrToYV12 = rgb24ToUV_c; break;
        case PIX_FMT_RGB565 : c->chrToYV12 = rgb16ToUV_c; break;
        case PIX_FMT_RGB555 : c->chrToYV12 = rgb15ToUV_c; break;
        }
    }

    c->lumToYV12 = NULL;
    c->alpToYV12 = NULL;
    switch (srcFormat) {
    case PIX_FMT_YUV420P9BE: c->lumToYV12 = BE9ToY_c; break;
    case PIX_FMT_YUV420P9LE: c->lumToYV12 = LE9ToY_c; break;
    case PIX_FMT_YUV420P10BE: c->lumToYV12 = BE10ToY_c; break;
    case PIX_FMT_YUV420P10LE: c->lumToYV12 = LE10ToY_c; break;
    case PIX_FMT_YUYV422  :
    case PIX_FMT_YUV420P16BE:
    case PIX_FMT_YUV422P16BE:
    case PIX_FMT_YUV444P16BE:
    case PIX_FMT_Y400A    :
    case PIX_FMT_GRAY16BE : c->lumToYV12 = yuy2ToY_c; break;
    case PIX_FMT_UYVY422  :
    case PIX_FMT_YUV420P16LE:
    case PIX_FMT_YUV422P16LE:
    case PIX_FMT_YUV444P16LE:
    case PIX_FMT_GRAY16LE : c->lumToYV12 = uyvyToY_c; break;
    case PIX_FMT_BGR24    : c->lumToYV12 = bgr24ToY_c; break;
    case PIX_FMT_BGR565   : c->lumToYV12 = bgr16ToY_c; break;
    case PIX_FMT_BGR555   : c->lumToYV12 = bgr15ToY_c; break;
    case PIX_FMT_RGB24    : c->lumToYV12 = rgb24ToY_c; break;
    case PIX_FMT_RGB565   : c->lumToYV12 = rgb16ToY_c; break;
    case PIX_FMT_RGB555   : c->lumToYV12 = rgb15ToY_c; break;
    case PIX_FMT_RGB8     :
    case PIX_FMT_BGR8     :
    case PIX_FMT_PAL8     :
    case PIX_FMT_BGR4_BYTE:
    case PIX_FMT_RGB4_BYTE: c->lumToYV12 = palToY_c; break;
    case PIX_FMT_MONOBLACK: c->lumToYV12 = monoblack2Y_c; break;
    case PIX_FMT_MONOWHITE: c->lumToYV12 = monowhite2Y_c; break;
    case PIX_FMT_RGB32  : c->lumToYV12 = bgr32ToY_c;  break;
    case PIX_FMT_RGB32_1: c->lumToYV12 = bgr321ToY_c; break;
    case PIX_FMT_BGR32  : c->lumToYV12 = rgb32ToY_c;  break;
    case PIX_FMT_BGR32_1: c->lumToYV12 = rgb321ToY_c; break;
    case PIX_FMT_RGB48BE: c->lumToYV12 = rgb48BEToY_c; break;
    case PIX_FMT_RGB48LE: c->lumToYV12 = rgb48LEToY_c; break;
    case PIX_FMT_BGR48BE: c->lumToYV12 = bgr48BEToY_c; break;
    case PIX_FMT_BGR48LE: c->lumToYV12 = bgr48LEToY_c; break;
    }
    if (c->alpPixBuf) {
        switch (srcFormat) {
        case PIX_FMT_BGRA:
        case PIX_FMT_RGBA:  c->alpToYV12 = rgbaToA_c; break;
        case PIX_FMT_ABGR:
        case PIX_FMT_ARGB:  c->alpToYV12 = abgrToA_c; break;
        case PIX_FMT_Y400A: c->alpToYV12 = uyvyToY_c; break;
        }
    }

    if (c->srcRange != c->dstRange && !isAnyRGB(c->dstFormat)) {
        if (c->srcRange) {
            c->lumConvertRange = lumRangeFromJpeg_c;
            c->chrConvertRange = chrRangeFromJpeg_c;
        } else {
            c->lumConvertRange = lumRangeToJpeg_c;
            c->chrConvertRange = chrRangeToJpeg_c;
        }
    }

    if (!(isGray(srcFormat) || isGray(c->dstFormat) ||
          srcFormat == PIX_FMT_MONOBLACK || srcFormat == PIX_FMT_MONOWHITE))
        c->needs_hcscale = 1;
}

SwsFunc ff_getSwsFunc(SwsContext *c)
{
    sws_init_swScale_c(c);

    if (HAVE_MMX)
        ff_sws_init_swScale_mmx(c);
    if (HAVE_ALTIVEC)
        ff_sws_init_swScale_altivec(c);

    return swScale;
}