/*
  * Copyright (C) 2001-2003 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
  */
 
 #define _SVID_SOURCE //needed for MAP_ANONYMOUS

 #define _DARWIN_C_SOURCE // needed for MAP_ANON

 #include <inttypes.h>
 #include <string.h>
 #include <math.h>
 #include <stdio.h>
 #include "config.h"
 #include <assert.h>
 #if HAVE_SYS_MMAN_H
 #include <sys/mman.h>
 #if defined(MAP_ANON) && !defined(MAP_ANONYMOUS)
 #define MAP_ANONYMOUS MAP_ANON
 #endif
 #endif
 #if HAVE_VIRTUALALLOC
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #endif
 #include "swscale.h"
 #include "swscale_internal.h"
 #include "rgb2rgb.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/x86_cpu.h"

 #include "libavutil/cpu.h"

 #include "libavutil/avutil.h"
 #include "libavutil/bswap.h"

 #include "libavutil/mathematics.h"

 #include "libavutil/opt.h"

 #include "libavutil/pixdesc.h"

 #include "libavutil/avassert.h"

 
 unsigned swscale_version(void)
 {
     return LIBSWSCALE_VERSION_INT;
 }
 
 const char *swscale_configuration(void)
 {

     return FFMPEG_CONFIGURATION;

 }
 
 const char *swscale_license(void)
 {
 #define LICENSE_PREFIX "libswscale license: "

     return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;

 }
 
 #define RET 0xC3 //near return opcode for x86
 

 typedef struct FormatEntry {

     int is_supported_in, is_supported_out;

 } FormatEntry;
 
 const static FormatEntry format_entries[PIX_FMT_NB] = {
     [PIX_FMT_YUV420P]     = { 1 , 1 },
     [PIX_FMT_YUYV422]     = { 1 , 1 },
     [PIX_FMT_RGB24]       = { 1 , 1 },
     [PIX_FMT_BGR24]       = { 1 , 1 },
     [PIX_FMT_YUV422P]     = { 1 , 1 },
     [PIX_FMT_YUV444P]     = { 1 , 1 },
     [PIX_FMT_YUV410P]     = { 1 , 1 },
     [PIX_FMT_YUV411P]     = { 1 , 1 },
     [PIX_FMT_GRAY8]       = { 1 , 1 },
     [PIX_FMT_MONOWHITE]   = { 1 , 1 },
     [PIX_FMT_MONOBLACK]   = { 1 , 1 },
     [PIX_FMT_PAL8]        = { 1 , 0 },
     [PIX_FMT_YUVJ420P]    = { 1 , 1 },
     [PIX_FMT_YUVJ422P]    = { 1 , 1 },
     [PIX_FMT_YUVJ444P]    = { 1 , 1 },
     [PIX_FMT_UYVY422]     = { 1 , 1 },
     [PIX_FMT_UYYVYY411]   = { 0 , 0 },
     [PIX_FMT_BGR8]        = { 1 , 1 },
     [PIX_FMT_BGR4]        = { 0 , 1 },
     [PIX_FMT_BGR4_BYTE]   = { 1 , 1 },
     [PIX_FMT_RGB8]        = { 1 , 1 },
     [PIX_FMT_RGB4]        = { 0 , 1 },
     [PIX_FMT_RGB4_BYTE]   = { 1 , 1 },
     [PIX_FMT_NV12]        = { 1 , 1 },
     [PIX_FMT_NV21]        = { 1 , 1 },
     [PIX_FMT_ARGB]        = { 1 , 1 },
     [PIX_FMT_RGBA]        = { 1 , 1 },
     [PIX_FMT_ABGR]        = { 1 , 1 },
     [PIX_FMT_BGRA]        = { 1 , 1 },

     [PIX_FMT_0RGB]        = { 1 , 1 },
     [PIX_FMT_RGB0]        = { 1 , 1 },
     [PIX_FMT_0BGR]        = { 1 , 1 },
     [PIX_FMT_BGR0]        = { 1 , 1 },

     [PIX_FMT_GRAY16BE]    = { 1 , 1 },
     [PIX_FMT_GRAY16LE]    = { 1 , 1 },
     [PIX_FMT_YUV440P]     = { 1 , 1 },
     [PIX_FMT_YUVJ440P]    = { 1 , 1 },
     [PIX_FMT_YUVA420P]    = { 1 , 1 },
     [PIX_FMT_RGB48BE]     = { 1 , 1 },
     [PIX_FMT_RGB48LE]     = { 1 , 1 },

     [PIX_FMT_RGBA64BE]    = { 0 , 0 },
     [PIX_FMT_RGBA64LE]    = { 0 , 0 },

     [PIX_FMT_RGB565BE]    = { 1 , 1 },
     [PIX_FMT_RGB565LE]    = { 1 , 1 },
     [PIX_FMT_RGB555BE]    = { 1 , 1 },
     [PIX_FMT_RGB555LE]    = { 1 , 1 },
     [PIX_FMT_BGR565BE]    = { 1 , 1 },
     [PIX_FMT_BGR565LE]    = { 1 , 1 },
     [PIX_FMT_BGR555BE]    = { 1 , 1 },
     [PIX_FMT_BGR555LE]    = { 1 , 1 },
     [PIX_FMT_YUV420P16LE] = { 1 , 1 },
     [PIX_FMT_YUV420P16BE] = { 1 , 1 },
     [PIX_FMT_YUV422P16LE] = { 1 , 1 },
     [PIX_FMT_YUV422P16BE] = { 1 , 1 },
     [PIX_FMT_YUV444P16LE] = { 1 , 1 },
     [PIX_FMT_YUV444P16BE] = { 1 , 1 },
     [PIX_FMT_RGB444LE]    = { 0 , 1 },
     [PIX_FMT_RGB444BE]    = { 0 , 1 },
     [PIX_FMT_BGR444LE]    = { 0 , 1 },
     [PIX_FMT_BGR444BE]    = { 0 , 1 },

     [PIX_FMT_Y400A]       = { 1 , 0 },

     [PIX_FMT_BGR48BE]     = { 1 , 1 },
     [PIX_FMT_BGR48LE]     = { 1 , 1 },

     [PIX_FMT_BGRA64BE]    = { 0 , 0 },
     [PIX_FMT_BGRA64LE]    = { 0 , 0 },

     [PIX_FMT_YUV420P9BE]  = { 1 , 1 },
     [PIX_FMT_YUV420P9LE]  = { 1 , 1 },
     [PIX_FMT_YUV420P10BE] = { 1 , 1 },
     [PIX_FMT_YUV420P10LE] = { 1 , 1 },

     [PIX_FMT_YUV422P9BE]  = { 1 , 1 },
     [PIX_FMT_YUV422P9LE]  = { 1 , 1 },

     [PIX_FMT_YUV422P10BE] = { 1 , 1 },
     [PIX_FMT_YUV422P10LE] = { 1 , 1 },

     [PIX_FMT_YUV444P9BE]  = { 1 , 1 },
     [PIX_FMT_YUV444P9LE]  = { 1 , 1 },
     [PIX_FMT_YUV444P10BE] = { 1 , 1 },
     [PIX_FMT_YUV444P10LE] = { 1 , 1 },

     [PIX_FMT_GBR24P]      = { 1 , 0 },

     [PIX_FMT_GBRP]        = { 1 , 0 },
     [PIX_FMT_GBRP9LE]     = { 1 , 0 },
     [PIX_FMT_GBRP9BE]     = { 1 , 0 },
     [PIX_FMT_GBRP10LE]    = { 1 , 0 },
     [PIX_FMT_GBRP10BE]    = { 1 , 0 },
     [PIX_FMT_GBRP16LE]    = { 1 , 0 },
     [PIX_FMT_GBRP16BE]    = { 1 , 0 },

 };
 

 int sws_isSupportedInput(enum PixelFormat pix_fmt)
 {

     return (unsigned)pix_fmt < PIX_FMT_NB ?
         format_entries[pix_fmt].is_supported_in : 0;

 }
 
 int sws_isSupportedOutput(enum PixelFormat pix_fmt)
 {

     return (unsigned)pix_fmt < PIX_FMT_NB ?
         format_entries[pix_fmt].is_supported_out : 0;

 }
 
 extern const int32_t ff_yuv2rgb_coeffs[8][4];
 

 #if FF_API_SWS_FORMAT_NAME
 const char *sws_format_name(enum PixelFormat format)
 {
     return av_get_pix_fmt_name(format);
 }
 #endif
 

 static double getSplineCoeff(double a, double b, double c, double d, double dist)
 {
     if (dist<=1.0) return ((d*dist + c)*dist + b)*dist +a;
     else           return getSplineCoeff(        0.0,
                                           b+ 2.0*c + 3.0*d,
                                                  c + 3.0*d,
                                          -b- 3.0*c - 6.0*d,
                                          dist-1.0);
 }
 
 static int initFilter(int16_t **outFilter, int16_t **filterPos, int *outFilterSize, int xInc,

                       int srcW, int dstW, int filterAlign, int one, int flags, int cpu_flags,

                       SwsVector *srcFilter, SwsVector *dstFilter, double param[2])
 {
     int i;
     int filterSize;
     int filter2Size;
     int minFilterSize;
     int64_t *filter=NULL;
     int64_t *filter2=NULL;
     const int64_t fone= 1LL<<54;
     int ret= -1;

     emms_c(); //FIXME this should not be required but it IS (even for non-MMX versions)

     // NOTE: the +3 is for the MMX(+1)/SSE(+3) scaler which reads over the end
     FF_ALLOC_OR_GOTO(NULL, *filterPos, (dstW+3)*sizeof(int16_t), fail);

 
     if (FFABS(xInc - 0x10000) <10) { // unscaled
         int i;
         filterSize= 1;
         FF_ALLOCZ_OR_GOTO(NULL, filter, dstW*sizeof(*filter)*filterSize, fail);
 
         for (i=0; i<dstW; i++) {
             filter[i*filterSize]= fone;
             (*filterPos)[i]=i;
         }
 
     } else if (flags&SWS_POINT) { // lame looking point sampling mode
         int i;

         int64_t xDstInSrc;

         filterSize= 1;
         FF_ALLOC_OR_GOTO(NULL, filter, dstW*sizeof(*filter)*filterSize, fail);
 
         xDstInSrc= xInc/2 - 0x8000;
         for (i=0; i<dstW; i++) {
             int xx= (xDstInSrc - ((filterSize-1)<<15) + (1<<15))>>16;
 
             (*filterPos)[i]= xx;
             filter[i]= fone;
             xDstInSrc+= xInc;
         }
     } else if ((xInc <= (1<<16) && (flags&SWS_AREA)) || (flags&SWS_FAST_BILINEAR)) { // bilinear upscale
         int i;

         int64_t xDstInSrc;

         filterSize= 2;
         FF_ALLOC_OR_GOTO(NULL, filter, dstW*sizeof(*filter)*filterSize, fail);
 
         xDstInSrc= xInc/2 - 0x8000;
         for (i=0; i<dstW; i++) {
             int xx= (xDstInSrc - ((filterSize-1)<<15) + (1<<15))>>16;
             int j;
 
             (*filterPos)[i]= xx;
             //bilinear upscale / linear interpolate / area averaging
             for (j=0; j<filterSize; j++) {

                 int64_t coeff= fone - FFABS(((int64_t)xx<<16) - xDstInSrc)*(fone>>16);

                 if (coeff<0) coeff=0;
                 filter[i*filterSize + j]= coeff;
                 xx++;
             }
             xDstInSrc+= xInc;
         }
     } else {

         int64_t xDstInSrc;

         int sizeFactor;
 
         if      (flags&SWS_BICUBIC)      sizeFactor=  4;
         else if (flags&SWS_X)            sizeFactor=  8;
         else if (flags&SWS_AREA)         sizeFactor=  1; //downscale only, for upscale it is bilinear
         else if (flags&SWS_GAUSS)        sizeFactor=  8;   // infinite ;)
         else if (flags&SWS_LANCZOS)      sizeFactor= param[0] != SWS_PARAM_DEFAULT ? ceil(2*param[0]) : 6;
         else if (flags&SWS_SINC)         sizeFactor= 20; // infinite ;)
         else if (flags&SWS_SPLINE)       sizeFactor= 20;  // infinite ;)
         else if (flags&SWS_BILINEAR)     sizeFactor=  2;
         else {
             sizeFactor= 0; //GCC warning killer
             assert(0);
         }
 
         if (xInc <= 1<<16)      filterSize= 1 + sizeFactor; // upscale
         else                    filterSize= 1 + (sizeFactor*srcW + dstW - 1)/ dstW;
 
         if (filterSize > srcW-2) filterSize=srcW-2;
 
         FF_ALLOC_OR_GOTO(NULL, filter, dstW*sizeof(*filter)*filterSize, fail);
 
         xDstInSrc= xInc - 0x10000;
         for (i=0; i<dstW; i++) {
             int xx= (xDstInSrc - ((filterSize-2)<<16)) / (1<<17);
             int j;
             (*filterPos)[i]= xx;
             for (j=0; j<filterSize; j++) {

                 int64_t d= (FFABS(((int64_t)xx<<17) - xDstInSrc))<<13;

                 double floatd;
                 int64_t coeff;
 
                 if (xInc > 1<<16)
                     d= d*dstW/srcW;
                 floatd= d * (1.0/(1<<30));
 
                 if (flags & SWS_BICUBIC) {
                     int64_t B= (param[0] != SWS_PARAM_DEFAULT ? param[0] :   0) * (1<<24);
                     int64_t C= (param[1] != SWS_PARAM_DEFAULT ? param[1] : 0.6) * (1<<24);
 

                     if (d >= 1LL<<31) {
                         coeff = 0.0;
                     } else {
                         int64_t dd  = (d  * d) >> 30;
                         int64_t ddd = (dd * d) >> 30;
 
                         if (d < 1LL<<30)
                             coeff = (12*(1<<24)-9*B-6*C)*ddd + (-18*(1<<24)+12*B+6*C)*dd + (6*(1<<24)-2*B)*(1<<30);
                         else
                             coeff = (-B-6*C)*ddd + (6*B+30*C)*dd + (-12*B-48*C)*d + (8*B+24*C)*(1<<30);
                     }

                     coeff *= fone>>(30+24);
                 }
 /*                else if (flags & SWS_X) {
                     double p= param ? param*0.01 : 0.3;

                     coeff = d ? sin(d*M_PI)/(d*M_PI) : 1.0;

                     coeff*= pow(2.0, - p*d*d);
                 }*/
                 else if (flags & SWS_X) {
                     double A= param[0] != SWS_PARAM_DEFAULT ? param[0] : 1.0;
                     double c;
 
                     if (floatd<1.0)

                         c = cos(floatd*M_PI);

                     else
                         c=-1.0;
                     if (c<0.0)      c= -pow(-c, A);
                     else            c=  pow( c, A);
                     coeff= (c*0.5 + 0.5)*fone;
                 } else if (flags & SWS_AREA) {
                     int64_t d2= d - (1<<29);
                     if      (d2*xInc < -(1LL<<(29+16))) coeff= 1.0 * (1LL<<(30+16));
                     else if (d2*xInc <  (1LL<<(29+16))) coeff= -d2*xInc + (1LL<<(29+16));
                     else coeff=0.0;
                     coeff *= fone>>(30+16);
                 } else if (flags & SWS_GAUSS) {
                     double p= param[0] != SWS_PARAM_DEFAULT ? param[0] : 3.0;
                     coeff = (pow(2.0, - p*floatd*floatd))*fone;
                 } else if (flags & SWS_SINC) {

                     coeff = (d ? sin(floatd*M_PI)/(floatd*M_PI) : 1.0)*fone;

                 } else if (flags & SWS_LANCZOS) {
                     double p= param[0] != SWS_PARAM_DEFAULT ? param[0] : 3.0;

                     coeff = (d ? sin(floatd*M_PI)*sin(floatd*M_PI/p)/(floatd*floatd*M_PI*M_PI/p) : 1.0)*fone;

                     if (floatd>p) coeff=0;
                 } else if (flags & SWS_BILINEAR) {
                     coeff= (1<<30) - d;
                     if (coeff<0) coeff=0;
                     coeff *= fone >> 30;
                 } else if (flags & SWS_SPLINE) {
                     double p=-2.196152422706632;
                     coeff = getSplineCoeff(1.0, 0.0, p, -p-1.0, floatd) * fone;
                 } else {
                     coeff= 0.0; //GCC warning killer
                     assert(0);
                 }
 
                 filter[i*filterSize + j]= coeff;
                 xx++;
             }
             xDstInSrc+= 2*xInc;
         }
     }
 
     /* apply src & dst Filter to filter -> filter2
        av_free(filter);
     */
     assert(filterSize>0);
     filter2Size= filterSize;
     if (srcFilter) filter2Size+= srcFilter->length - 1;
     if (dstFilter) filter2Size+= dstFilter->length - 1;
     assert(filter2Size>0);
     FF_ALLOCZ_OR_GOTO(NULL, filter2, filter2Size*dstW*sizeof(*filter2), fail);
 
     for (i=0; i<dstW; i++) {
         int j, k;
 
         if(srcFilter) {
             for (k=0; k<srcFilter->length; k++) {
                 for (j=0; j<filterSize; j++)
                     filter2[i*filter2Size + k + j] += srcFilter->coeff[k]*filter[i*filterSize + j];
             }
         } else {
             for (j=0; j<filterSize; j++)
                 filter2[i*filter2Size + j]= filter[i*filterSize + j];
         }
         //FIXME dstFilter
 
         (*filterPos)[i]+= (filterSize-1)/2 - (filter2Size-1)/2;
     }
     av_freep(&filter);
 
     /* try to reduce the filter-size (step1 find size and shift left) */
     // Assume it is near normalized (*0.5 or *2.0 is OK but * 0.001 is not).
     minFilterSize= 0;
     for (i=dstW-1; i>=0; i--) {
         int min= filter2Size;
         int j;
         int64_t cutOff=0.0;
 
         /* get rid of near zero elements on the left by shifting left */
         for (j=0; j<filter2Size; j++) {
             int k;
             cutOff += FFABS(filter2[i*filter2Size]);
 
             if (cutOff > SWS_MAX_REDUCE_CUTOFF*fone) break;
 
             /* preserve monotonicity because the core can't handle the filter otherwise */
             if (i<dstW-1 && (*filterPos)[i] >= (*filterPos)[i+1]) break;
 
             // move filter coefficients left
             for (k=1; k<filter2Size; k++)
                 filter2[i*filter2Size + k - 1]= filter2[i*filter2Size + k];
             filter2[i*filter2Size + k - 1]= 0;
             (*filterPos)[i]++;
         }
 
         cutOff=0;
         /* count near zeros on the right */
         for (j=filter2Size-1; j>0; j--) {
             cutOff += FFABS(filter2[i*filter2Size + j]);
 
             if (cutOff > SWS_MAX_REDUCE_CUTOFF*fone) break;
             min--;
         }
 
         if (min>minFilterSize) minFilterSize= min;
     }
 

     if (HAVE_ALTIVEC && cpu_flags & AV_CPU_FLAG_ALTIVEC) {

         // we can handle the special case 4,
         // so we don't want to go to the full 8
         if (minFilterSize < 5)
             filterAlign = 4;
 
         // We really don't want to waste our time
         // doing useless computation, so fall back on
         // the scalar C code for very small filters.
         // Vectorizing is worth it only if you have a
         // decent-sized vector.
         if (minFilterSize < 3)
             filterAlign = 1;
     }
 

     if (HAVE_MMX && cpu_flags & AV_CPU_FLAG_MMX) {

         // special case for unscaled vertical filtering
         if (minFilterSize == 1 && filterAlign == 2)
             filterAlign= 1;
     }
 
     assert(minFilterSize > 0);
     filterSize= (minFilterSize +(filterAlign-1)) & (~(filterAlign-1));
     assert(filterSize > 0);
     filter= av_malloc(filterSize*dstW*sizeof(*filter));
     if (filterSize >= MAX_FILTER_SIZE*16/((flags&SWS_ACCURATE_RND) ? APCK_SIZE : 16) || !filter)
         goto fail;
     *outFilterSize= filterSize;
 
     if (flags&SWS_PRINT_INFO)
         av_log(NULL, AV_LOG_VERBOSE, "SwScaler: reducing / aligning filtersize %d -> %d\n", filter2Size, filterSize);
     /* try to reduce the filter-size (step2 reduce it) */
     for (i=0; i<dstW; i++) {
         int j;
 
         for (j=0; j<filterSize; j++) {
             if (j>=filter2Size) filter[i*filterSize + j]= 0;
             else               filter[i*filterSize + j]= filter2[i*filter2Size + j];
             if((flags & SWS_BITEXACT) && j>=minFilterSize)
                 filter[i*filterSize + j]= 0;
         }
     }
 
     //FIXME try to align filterPos if possible
 
     //fix borders
     for (i=0; i<dstW; i++) {
         int j;
         if ((*filterPos)[i] < 0) {
             // move filter coefficients left to compensate for filterPos
             for (j=1; j<filterSize; j++) {
                 int left= FFMAX(j + (*filterPos)[i], 0);
                 filter[i*filterSize + left] += filter[i*filterSize + j];
                 filter[i*filterSize + j]=0;
             }
             (*filterPos)[i]= 0;
         }
 
         if ((*filterPos)[i] + filterSize > srcW) {
             int shift= (*filterPos)[i] + filterSize - srcW;
             // move filter coefficients right to compensate for filterPos
             for (j=filterSize-2; j>=0; j--) {
                 int right= FFMIN(j + shift, filterSize-1);
                 filter[i*filterSize +right] += filter[i*filterSize +j];
                 filter[i*filterSize +j]=0;
             }
             (*filterPos)[i]= srcW - filterSize;
         }
     }
 
     // Note the +1 is for the MMX scaler which reads over the end
     /* align at 16 for AltiVec (needed by hScale_altivec_real) */

     FF_ALLOCZ_OR_GOTO(NULL, *outFilter, *outFilterSize*(dstW+3)*sizeof(int16_t), fail);

 
     /* normalize & store in outFilter */
     for (i=0; i<dstW; i++) {
         int j;
         int64_t error=0;
         int64_t sum=0;
 
         for (j=0; j<filterSize; j++) {
             sum+= filter[i*filterSize + j];
         }
         sum= (sum + one/2)/ one;
         for (j=0; j<*outFilterSize; j++) {
             int64_t v= filter[i*filterSize + j] + error;
             int intV= ROUNDED_DIV(v, sum);
             (*outFilter)[i*(*outFilterSize) + j]= intV;
             error= v - intV*sum;
         }
     }
 

     (*filterPos)[dstW+0] =
     (*filterPos)[dstW+1] =
     (*filterPos)[dstW+2] = (*filterPos)[dstW-1]; // the MMX/SSE scaler will read over the end

     for (i=0; i<*outFilterSize; i++) {

         int k= (dstW - 1) * (*outFilterSize) + i;
         (*outFilter)[k + 1 * (*outFilterSize)] =
         (*outFilter)[k + 2 * (*outFilterSize)] =
         (*outFilter)[k + 3 * (*outFilterSize)] = (*outFilter)[k];

     }
 
     ret=0;
 fail:
     av_free(filter);
     av_free(filter2);
     return ret;
 }
 

 #if HAVE_MMX2

 static int initMMX2HScaler(int dstW, int xInc, uint8_t *filterCode, int16_t *filter, int32_t *filterPos, int numSplits)
 {
     uint8_t *fragmentA;
     x86_reg imm8OfPShufW1A;
     x86_reg imm8OfPShufW2A;
     x86_reg fragmentLengthA;
     uint8_t *fragmentB;
     x86_reg imm8OfPShufW1B;
     x86_reg imm8OfPShufW2B;
     x86_reg fragmentLengthB;
     int fragmentPos;
 
     int xpos, i;
 
     // create an optimized horizontal scaling routine
     /* This scaler is made of runtime-generated MMX2 code using specially
      * tuned pshufw instructions. For every four output pixels, if four
      * input pixels are enough for the fast bilinear scaling, then a chunk
      * of fragmentB is used. If five input pixels are needed, then a chunk
      * of fragmentA is used.
      */
 
     //code fragment
 
     __asm__ volatile(
         "jmp                         9f                 \n\t"
     // Begin
         "0:                                             \n\t"
         "movq    (%%"REG_d", %%"REG_a"), %%mm3          \n\t"
         "movd    (%%"REG_c", %%"REG_S"), %%mm0          \n\t"
         "movd   1(%%"REG_c", %%"REG_S"), %%mm1          \n\t"
         "punpcklbw                %%mm7, %%mm1          \n\t"
         "punpcklbw                %%mm7, %%mm0          \n\t"
         "pshufw                   $0xFF, %%mm1, %%mm1   \n\t"
         "1:                                             \n\t"
         "pshufw                   $0xFF, %%mm0, %%mm0   \n\t"
         "2:                                             \n\t"
         "psubw                    %%mm1, %%mm0          \n\t"
         "movl   8(%%"REG_b", %%"REG_a"), %%esi          \n\t"
         "pmullw                   %%mm3, %%mm0          \n\t"
         "psllw                       $7, %%mm1          \n\t"
         "paddw                    %%mm1, %%mm0          \n\t"
 
         "movq                     %%mm0, (%%"REG_D", %%"REG_a") \n\t"
 
         "add                         $8, %%"REG_a"      \n\t"
     // End
         "9:                                             \n\t"
 //        "int $3                                         \n\t"
         "lea                 " LOCAL_MANGLE(0b) ", %0   \n\t"
         "lea                 " LOCAL_MANGLE(1b) ", %1   \n\t"
         "lea                 " LOCAL_MANGLE(2b) ", %2   \n\t"
         "dec                         %1                 \n\t"
         "dec                         %2                 \n\t"
         "sub                         %0, %1             \n\t"
         "sub                         %0, %2             \n\t"
         "lea                 " LOCAL_MANGLE(9b) ", %3   \n\t"
         "sub                         %0, %3             \n\t"
 
 
         :"=r" (fragmentA), "=r" (imm8OfPShufW1A), "=r" (imm8OfPShufW2A),
         "=r" (fragmentLengthA)
     );
 
     __asm__ volatile(
         "jmp                         9f                 \n\t"
     // Begin
         "0:                                             \n\t"
         "movq    (%%"REG_d", %%"REG_a"), %%mm3          \n\t"
         "movd    (%%"REG_c", %%"REG_S"), %%mm0          \n\t"
         "punpcklbw                %%mm7, %%mm0          \n\t"
         "pshufw                   $0xFF, %%mm0, %%mm1   \n\t"
         "1:                                             \n\t"
         "pshufw                   $0xFF, %%mm0, %%mm0   \n\t"
         "2:                                             \n\t"
         "psubw                    %%mm1, %%mm0          \n\t"
         "movl   8(%%"REG_b", %%"REG_a"), %%esi          \n\t"
         "pmullw                   %%mm3, %%mm0          \n\t"
         "psllw                       $7, %%mm1          \n\t"
         "paddw                    %%mm1, %%mm0          \n\t"
 
         "movq                     %%mm0, (%%"REG_D", %%"REG_a") \n\t"
 
         "add                         $8, %%"REG_a"      \n\t"
     // End
         "9:                                             \n\t"
 //        "int                       $3                   \n\t"
         "lea                 " LOCAL_MANGLE(0b) ", %0   \n\t"
         "lea                 " LOCAL_MANGLE(1b) ", %1   \n\t"
         "lea                 " LOCAL_MANGLE(2b) ", %2   \n\t"
         "dec                         %1                 \n\t"
         "dec                         %2                 \n\t"
         "sub                         %0, %1             \n\t"
         "sub                         %0, %2             \n\t"
         "lea                 " LOCAL_MANGLE(9b) ", %3   \n\t"
         "sub                         %0, %3             \n\t"
 
 
         :"=r" (fragmentB), "=r" (imm8OfPShufW1B), "=r" (imm8OfPShufW2B),
         "=r" (fragmentLengthB)
     );
 
     xpos= 0; //lumXInc/2 - 0x8000; // difference between pixel centers
     fragmentPos=0;
 
     for (i=0; i<dstW/numSplits; i++) {
         int xx=xpos>>16;
 
         if ((i&3) == 0) {
             int a=0;
             int b=((xpos+xInc)>>16) - xx;
             int c=((xpos+xInc*2)>>16) - xx;
             int d=((xpos+xInc*3)>>16) - xx;
             int inc                = (d+1<4);
             uint8_t *fragment      = (d+1<4) ? fragmentB       : fragmentA;
             x86_reg imm8OfPShufW1  = (d+1<4) ? imm8OfPShufW1B  : imm8OfPShufW1A;
             x86_reg imm8OfPShufW2  = (d+1<4) ? imm8OfPShufW2B  : imm8OfPShufW2A;
             x86_reg fragmentLength = (d+1<4) ? fragmentLengthB : fragmentLengthA;
             int maxShift= 3-(d+inc);
             int shift=0;
 
             if (filterCode) {
                 filter[i  ] = (( xpos         & 0xFFFF) ^ 0xFFFF)>>9;
                 filter[i+1] = (((xpos+xInc  ) & 0xFFFF) ^ 0xFFFF)>>9;
                 filter[i+2] = (((xpos+xInc*2) & 0xFFFF) ^ 0xFFFF)>>9;
                 filter[i+3] = (((xpos+xInc*3) & 0xFFFF) ^ 0xFFFF)>>9;
                 filterPos[i/2]= xx;
 
                 memcpy(filterCode + fragmentPos, fragment, fragmentLength);
 
                 filterCode[fragmentPos + imm8OfPShufW1]=
                     (a+inc) | ((b+inc)<<2) | ((c+inc)<<4) | ((d+inc)<<6);
                 filterCode[fragmentPos + imm8OfPShufW2]=
                     a | (b<<2) | (c<<4) | (d<<6);
 
                 if (i+4-inc>=dstW) shift=maxShift; //avoid overread
                 else if ((filterPos[i/2]&3) <= maxShift) shift=filterPos[i/2]&3; //Align
 
                 if (shift && i>=shift) {
                     filterCode[fragmentPos + imm8OfPShufW1]+= 0x55*shift;
                     filterCode[fragmentPos + imm8OfPShufW2]+= 0x55*shift;
                     filterPos[i/2]-=shift;
                 }
             }
 
             fragmentPos+= fragmentLength;
 
             if (filterCode)
                 filterCode[fragmentPos]= RET;
         }
         xpos+=xInc;
     }
     if (filterCode)
         filterPos[((i/2)+1)&(~1)]= xpos>>16; // needed to jump to the next part
 
     return fragmentPos + 1;
 }

 #endif /* HAVE_MMX2 */

 
 static void getSubSampleFactors(int *h, int *v, enum PixelFormat format)
 {
     *h = av_pix_fmt_descriptors[format].log2_chroma_w;
     *v = av_pix_fmt_descriptors[format].log2_chroma_h;
 }
 

 int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4],
                              int srcRange, const int table[4], int dstRange,
                              int brightness, int contrast, int saturation)

 {
     memcpy(c->srcColorspaceTable, inv_table, sizeof(int)*4);
     memcpy(c->dstColorspaceTable,     table, sizeof(int)*4);
 
     c->brightness= brightness;
     c->contrast  = contrast;
     c->saturation= saturation;
     c->srcRange  = srcRange;
     c->dstRange  = dstRange;
     if (isYUV(c->dstFormat) || isGray(c->dstFormat)) return -1;
 

     c->dstFormatBpp = av_get_bits_per_pixel(&av_pix_fmt_descriptors[c->dstFormat]);
     c->srcFormatBpp = av_get_bits_per_pixel(&av_pix_fmt_descriptors[c->srcFormat]);
 

     ff_yuv2rgb_c_init_tables(c, inv_table, srcRange, brightness, contrast, saturation);
     //FIXME factorize
 

     if (HAVE_ALTIVEC && av_get_cpu_flags() & AV_CPU_FLAG_ALTIVEC)

         ff_yuv2rgb_init_tables_altivec(c, inv_table, brightness, contrast, saturation);
     return 0;
 }
 

 int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
                              int *srcRange, int **table, int *dstRange,
                              int *brightness, int *contrast, int *saturation)

 {

     if (!c || isYUV(c->dstFormat) || isGray(c->dstFormat)) return -1;

 
     *inv_table = c->srcColorspaceTable;
     *table     = c->dstColorspaceTable;
     *srcRange  = c->srcRange;
     *dstRange  = c->dstRange;
     *brightness= c->brightness;
     *contrast  = c->contrast;
     *saturation= c->saturation;
 
     return 0;
 }
 
 static int handle_jpeg(enum PixelFormat *format)
 {
     switch (*format) {

     case PIX_FMT_YUVJ420P: *format = PIX_FMT_YUV420P; return 1;
     case PIX_FMT_YUVJ422P: *format = PIX_FMT_YUV422P; return 1;
     case PIX_FMT_YUVJ444P: *format = PIX_FMT_YUV444P; return 1;
     case PIX_FMT_YUVJ440P: *format = PIX_FMT_YUV440P; return 1;

     case PIX_FMT_0BGR    : *format = PIX_FMT_ABGR   ; return 0;
     case PIX_FMT_BGR0    : *format = PIX_FMT_BGRA   ; return 0;
     case PIX_FMT_0RGB    : *format = PIX_FMT_ARGB   ; return 0;
     case PIX_FMT_RGB0    : *format = PIX_FMT_RGBA   ; return 0;

     default:                                          return 0;

     }
 }
 

 SwsContext *sws_alloc_context(void)
 {

     SwsContext *c= av_mallocz(sizeof(SwsContext));
 
     c->av_class = &sws_context_class;

     av_opt_set_defaults(c);

 
     return c;
 }
 

 int sws_init_context(SwsContext *c, SwsFilter *srcFilter, SwsFilter *dstFilter)
 {

     int i, j;

     int usesVFilter, usesHFilter;
     int unscaled;
     SwsFilter dummyFilter= {NULL, NULL, NULL, NULL};

     int srcW= c->srcW;
     int srcH= c->srcH;
     int dstW= c->dstW;
     int dstH= c->dstH;

     int dst_stride = FFALIGN(dstW * sizeof(int16_t)+66, 16);

     int flags, cpu_flags;

     enum PixelFormat srcFormat= c->srcFormat;
     enum PixelFormat dstFormat= c->dstFormat;
 

     cpu_flags = av_get_cpu_flags();
     flags     = c->flags;

     emms_c();

     if (!rgb15to16) sws_rgb2rgb_init();

 
     unscaled = (srcW == dstW && srcH == dstH);
 

     handle_jpeg(&srcFormat);
     handle_jpeg(&dstFormat);
 
     if(srcFormat!=c->srcFormat || dstFormat!=c->dstFormat){
         av_log(c, AV_LOG_WARNING, "deprecated pixel format used, make sure you did set range correctly\n");
         c->srcFormat= srcFormat;
         c->dstFormat= dstFormat;
     }
 

     if (!sws_isSupportedInput(srcFormat)) {

         av_log(c, AV_LOG_ERROR, "%s is not supported as input pixel format\n", av_get_pix_fmt_name(srcFormat));

         return AVERROR(EINVAL);

     }

     if (!sws_isSupportedOutput(dstFormat)) {

         av_log(c, AV_LOG_ERROR, "%s is not supported as output pixel format\n", av_get_pix_fmt_name(dstFormat));

         return AVERROR(EINVAL);

     }
 
     i= flags & ( SWS_POINT
                 |SWS_AREA
                 |SWS_BILINEAR
                 |SWS_FAST_BILINEAR
                 |SWS_BICUBIC
                 |SWS_X
                 |SWS_GAUSS
                 |SWS_LANCZOS
                 |SWS_SINC
                 |SWS_SPLINE
                 |SWS_BICUBLIN);
     if(!i || (i & (i-1))) {

         av_log(c, AV_LOG_ERROR, "Exactly one scaler algorithm must be chosen\n");

         return AVERROR(EINVAL);

     }
     /* sanity check */
     if (srcW<4 || srcH<1 || dstW<8 || dstH<1) { //FIXME check if these are enough and try to lowwer them after fixing the relevant parts of the code

         av_log(c, AV_LOG_ERROR, "%dx%d -> %dx%d is invalid scaling dimension\n",

                srcW, srcH, dstW, dstH);

         return AVERROR(EINVAL);

     }
 
     if (!dstFilter) dstFilter= &dummyFilter;
     if (!srcFilter) srcFilter= &dummyFilter;
 
     c->lumXInc= ((srcW<<16) + (dstW>>1))/dstW;
     c->lumYInc= ((srcH<<16) + (dstH>>1))/dstH;

     c->dstFormatBpp = av_get_bits_per_pixel(&av_pix_fmt_descriptors[dstFormat]);
     c->srcFormatBpp = av_get_bits_per_pixel(&av_pix_fmt_descriptors[srcFormat]);

     c->vRounder= 4* 0x0001000100010001ULL;
 

     usesVFilter = (srcFilter->lumV && srcFilter->lumV->length>1) ||
                   (srcFilter->chrV && srcFilter->chrV->length>1) ||
                   (dstFilter->lumV && dstFilter->lumV->length>1) ||
                   (dstFilter->chrV && dstFilter->chrV->length>1);
     usesHFilter = (srcFilter->lumH && srcFilter->lumH->length>1) ||
                   (srcFilter->chrH && srcFilter->chrH->length>1) ||
                   (dstFilter->lumH && dstFilter->lumH->length>1) ||
                   (dstFilter->chrH && dstFilter->chrH->length>1);

 
     getSubSampleFactors(&c->chrSrcHSubSample, &c->chrSrcVSubSample, srcFormat);
     getSubSampleFactors(&c->chrDstHSubSample, &c->chrDstVSubSample, dstFormat);
 
     // reuse chroma for 2 pixels RGB/BGR unless user wants full chroma interpolation

     if (isAnyRGB(dstFormat) && !(flags&SWS_FULL_CHR_H_INT)) c->chrDstHSubSample=1;

 
     // drop some chroma lines if the user wants it
     c->vChrDrop= (flags&SWS_SRC_V_CHR_DROP_MASK)>>SWS_SRC_V_CHR_DROP_SHIFT;
     c->chrSrcVSubSample+= c->vChrDrop;
 
     // drop every other pixel for chroma calculation unless user wants full chroma

     if (isAnyRGB(srcFormat) && !(flags&SWS_FULL_CHR_H_INP)

       && srcFormat!=PIX_FMT_RGB8      && srcFormat!=PIX_FMT_BGR8
       && srcFormat!=PIX_FMT_RGB4      && srcFormat!=PIX_FMT_BGR4
       && srcFormat!=PIX_FMT_RGB4_BYTE && srcFormat!=PIX_FMT_BGR4_BYTE

       && ((dstW>>c->chrDstHSubSample) <= (srcW>>1) || (flags&SWS_FAST_BILINEAR)))

         c->chrSrcHSubSample=1;
 
     // Note the -((-x)>>y) is so that we always round toward +inf.
     c->chrSrcW= -((-srcW) >> c->chrSrcHSubSample);
     c->chrSrcH= -((-srcH) >> c->chrSrcVSubSample);
     c->chrDstW= -((-dstW) >> c->chrDstHSubSample);
     c->chrDstH= -((-dstH) >> c->chrDstVSubSample);
 
     /* unscaled special cases */

     if (unscaled && !usesHFilter && !usesVFilter && (c->srcRange == c->dstRange || isAnyRGB(dstFormat))) {

         ff_get_unscaled_swscale(c);
 
         if (c->swScale) {
             if (flags&SWS_PRINT_INFO)
                 av_log(c, AV_LOG_INFO, "using unscaled %s -> %s special converter\n",

                        av_get_pix_fmt_name(srcFormat), av_get_pix_fmt_name(dstFormat));

             return 0;

         }
     }
 

     c->srcBpc = 1 + av_pix_fmt_descriptors[srcFormat].comp[0].depth_minus1;
     if (c->srcBpc < 8)
         c->srcBpc = 8;
     c->dstBpc = 1 + av_pix_fmt_descriptors[dstFormat].comp[0].depth_minus1;
     if (c->dstBpc < 8)
         c->dstBpc = 8;

     if (isAnyRGB(srcFormat) || srcFormat == PIX_FMT_PAL8)

         c->srcBpc = 16;

     if (c->dstBpc == 16)

         dst_stride <<= 1;

     FF_ALLOC_OR_GOTO(c, c->formatConvBuffer, FFALIGN(srcW*2+78, 16) * 2, fail);

     if (HAVE_MMX2 && cpu_flags & AV_CPU_FLAG_MMX2 && c->srcBpc == 8 && c->dstBpc <= 10) {

         c->canMMX2BeUsed= (dstW >=srcW && (dstW&31)==0 && (srcW&15)==0) ? 1 : 0;
         if (!c->canMMX2BeUsed && dstW >=srcW && (srcW&15)==0 && (flags&SWS_FAST_BILINEAR)) {
             if (flags&SWS_PRINT_INFO)
                 av_log(c, AV_LOG_INFO, "output width is not a multiple of 32 -> no MMX2 scaler\n");
         }

         if (usesHFilter || isNBPS(c->srcFormat) || is16BPS(c->srcFormat) || isAnyRGB(c->srcFormat)) c->canMMX2BeUsed=0;

     }
     else
         c->canMMX2BeUsed=0;
 
     c->chrXInc= ((c->chrSrcW<<16) + (c->chrDstW>>1))/c->chrDstW;
     c->chrYInc= ((c->chrSrcH<<16) + (c->chrDstH>>1))/c->chrDstH;
 
     // match pixel 0 of the src to pixel 0 of dst and match pixel n-2 of src to pixel n-2 of dst
     // but only for the FAST_BILINEAR mode otherwise do correct scaling
     // n-2 is the last chrominance sample available
     // this is not perfect, but no one should notice the difference, the more correct variant
     // would be like the vertical one, but that would require some special code for the
     // first and last pixel
     if (flags&SWS_FAST_BILINEAR) {
         if (c->canMMX2BeUsed) {
             c->lumXInc+= 20;
             c->chrXInc+= 20;
         }
         //we don't use the x86 asm scaler if MMX is available

         else if (HAVE_MMX && cpu_flags & AV_CPU_FLAG_MMX && c->dstBpc <= 10) {

             c->lumXInc = ((srcW-2)<<16)/(dstW-2) - 20;
             c->chrXInc = ((c->chrSrcW-2)<<16)/(c->chrDstW-2) - 20;
         }
     }
 
     /* precalculate horizontal scaler filter coefficients */
     {

 #if HAVE_MMX2

 // can't downscale !!!
         if (c->canMMX2BeUsed && (flags & SWS_FAST_BILINEAR)) {
             c->lumMmx2FilterCodeSize = initMMX2HScaler(      dstW, c->lumXInc, NULL, NULL, NULL, 8);
             c->chrMmx2FilterCodeSize = initMMX2HScaler(c->chrDstW, c->chrXInc, NULL, NULL, NULL, 4);
 
 #ifdef MAP_ANONYMOUS

             c->lumMmx2FilterCode = mmap(NULL, c->lumMmx2FilterCodeSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
             c->chrMmx2FilterCode = mmap(NULL, c->chrMmx2FilterCodeSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);

 #elif HAVE_VIRTUALALLOC
             c->lumMmx2FilterCode = VirtualAlloc(NULL, c->lumMmx2FilterCodeSize, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
             c->chrMmx2FilterCode = VirtualAlloc(NULL, c->chrMmx2FilterCodeSize, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
 #else
             c->lumMmx2FilterCode = av_malloc(c->lumMmx2FilterCodeSize);
             c->chrMmx2FilterCode = av_malloc(c->chrMmx2FilterCodeSize);
 #endif
 

 #ifdef MAP_ANONYMOUS
             if (c->lumMmx2FilterCode == MAP_FAILED || c->chrMmx2FilterCode == MAP_FAILED)
 #else

             if (!c->lumMmx2FilterCode || !c->chrMmx2FilterCode)

 #endif

                 return AVERROR(ENOMEM);

             FF_ALLOCZ_OR_GOTO(c, c->hLumFilter   , (dstW        /8+8)*sizeof(int16_t), fail);
             FF_ALLOCZ_OR_GOTO(c, c->hChrFilter   , (c->chrDstW  /4+8)*sizeof(int16_t), fail);
             FF_ALLOCZ_OR_GOTO(c, c->hLumFilterPos, (dstW      /2/8+8)*sizeof(int32_t), fail);
             FF_ALLOCZ_OR_GOTO(c, c->hChrFilterPos, (c->chrDstW/2/4+8)*sizeof(int32_t), fail);
 

             initMMX2HScaler(      dstW, c->lumXInc, c->lumMmx2FilterCode, c->hLumFilter, (uint32_t*)c->hLumFilterPos, 8);
             initMMX2HScaler(c->chrDstW, c->chrXInc, c->chrMmx2FilterCode, c->hChrFilter, (uint32_t*)c->hChrFilterPos, 4);

 
 #ifdef MAP_ANONYMOUS
             mprotect(c->lumMmx2FilterCode, c->lumMmx2FilterCodeSize, PROT_EXEC | PROT_READ);
             mprotect(c->chrMmx2FilterCode, c->chrMmx2FilterCodeSize, PROT_EXEC | PROT_READ);
 #endif
         } else

 #endif /* HAVE_MMX2 */

         {
             const int filterAlign=

                 (HAVE_MMX     && cpu_flags & AV_CPU_FLAG_MMX) ? 4 :
                 (HAVE_ALTIVEC && cpu_flags & AV_CPU_FLAG_ALTIVEC) ? 8 :

                 1;
 
             if (initFilter(&c->hLumFilter, &c->hLumFilterPos, &c->hLumFilterSize, c->lumXInc,
                            srcW      ,       dstW, filterAlign, 1<<14,

                            (flags&SWS_BICUBLIN) ? (flags|SWS_BICUBIC)  : flags, cpu_flags,

                            srcFilter->lumH, dstFilter->lumH, c->param) < 0)
                 goto fail;
             if (initFilter(&c->hChrFilter, &c->hChrFilterPos, &c->hChrFilterSize, c->chrXInc,
                            c->chrSrcW, c->chrDstW, filterAlign, 1<<14,

                            (flags&SWS_BICUBLIN) ? (flags|SWS_BILINEAR) : flags, cpu_flags,

                            srcFilter->chrH, dstFilter->chrH, c->param) < 0)
                 goto fail;
         }
     } // initialize horizontal stuff
 
     /* precalculate vertical scaler filter coefficients */
     {
         const int filterAlign=

             (HAVE_MMX     && cpu_flags & AV_CPU_FLAG_MMX) ? 2 :

             (HAVE_ALTIVEC && cpu_flags & AV_CPU_FLAG_ALTIVEC) ? 8 :

             1;
 
         if (initFilter(&c->vLumFilter, &c->vLumFilterPos, &c->vLumFilterSize, c->lumYInc,
                        srcH      ,        dstH, filterAlign, (1<<12),

                        (flags&SWS_BICUBLIN) ? (flags|SWS_BICUBIC)  : flags, cpu_flags,

                        srcFilter->lumV, dstFilter->lumV, c->param) < 0)
             goto fail;
         if (initFilter(&c->vChrFilter, &c->vChrFilterPos, &c->vChrFilterSize, c->chrYInc,
                        c->chrSrcH, c->chrDstH, filterAlign, (1<<12),

                        (flags&SWS_BICUBLIN) ? (flags|SWS_BILINEAR) : flags, cpu_flags,

                        srcFilter->chrV, dstFilter->chrV, c->param) < 0)
             goto fail;
 

 #if HAVE_ALTIVEC

         FF_ALLOC_OR_GOTO(c, c->vYCoeffsBank, sizeof (vector signed short)*c->vLumFilterSize*c->dstH, fail);
         FF_ALLOC_OR_GOTO(c, c->vCCoeffsBank, sizeof (vector signed short)*c->vChrFilterSize*c->chrDstH, fail);
 
         for (i=0;i<c->vLumFilterSize*c->dstH;i++) {
             int j;
             short *p = (short *)&c->vYCoeffsBank[i];
             for (j=0;j<8;j++)
                 p[j] = c->vLumFilter[i];
         }
 
         for (i=0;i<c->vChrFilterSize*c->chrDstH;i++) {
             int j;
             short *p = (short *)&c->vCCoeffsBank[i];
             for (j=0;j<8;j++)
                 p[j] = c->vChrFilter[i];
         }
 #endif
     }
 
     // calculate buffer sizes so that they won't run out while handling these damn slices
     c->vLumBufSize= c->vLumFilterSize;
     c->vChrBufSize= c->vChrFilterSize;
     for (i=0; i<dstH; i++) {

         int chrI= (int64_t)i*c->chrDstH / dstH;

         int nextSlice= FFMAX(c->vLumFilterPos[i   ] + c->vLumFilterSize - 1,
                            ((c->vChrFilterPos[chrI] + c->vChrFilterSize - 1)<<c->chrSrcVSubSample));
 
         nextSlice>>= c->chrSrcVSubSample;
         nextSlice<<= c->chrSrcVSubSample;
         if (c->vLumFilterPos[i   ] + c->vLumBufSize < nextSlice)
             c->vLumBufSize= nextSlice - c->vLumFilterPos[i];
         if (c->vChrFilterPos[chrI] + c->vChrBufSize < (nextSlice>>c->chrSrcVSubSample))
             c->vChrBufSize= (nextSlice>>c->chrSrcVSubSample) - c->vChrFilterPos[chrI];
     }
 
     // allocate pixbufs (we use dynamic allocation because otherwise we would need to
     // allocate several megabytes to handle all possible cases)
     FF_ALLOC_OR_GOTO(c, c->lumPixBuf, c->vLumBufSize*2*sizeof(int16_t*), fail);

     FF_ALLOC_OR_GOTO(c, c->chrUPixBuf, c->vChrBufSize*2*sizeof(int16_t*), fail);
     FF_ALLOC_OR_GOTO(c, c->chrVPixBuf, c->vChrBufSize*2*sizeof(int16_t*), fail);

     if (CONFIG_SWSCALE_ALPHA && isALPHA(c->srcFormat) && isALPHA(c->dstFormat))
         FF_ALLOCZ_OR_GOTO(c, c->alpPixBuf, c->vLumBufSize*2*sizeof(int16_t*), fail);
     //Note we need at least one pixel more at the end because of the MMX code (just in case someone wanna replace the 4000/8000)
     /* align at 16 bytes for AltiVec */
     for (i=0; i<c->vLumBufSize; i++) {

         FF_ALLOCZ_OR_GOTO(c, c->lumPixBuf[i+c->vLumBufSize], dst_stride+16, fail);

         c->lumPixBuf[i] = c->lumPixBuf[i+c->vLumBufSize];
     }

     // 64 / c->scalingBpp is the same as 16 / sizeof(scaling_intermediate)

     c->uv_off   = (dst_stride>>1) + 64 / (c->dstBpc &~ 7);

     c->uv_offx2 = dst_stride + 16;

     for (i=0; i<c->vChrBufSize; i++) {

         FF_ALLOC_OR_GOTO(c, c->chrUPixBuf[i+c->vChrBufSize], dst_stride*2+32, fail);

         c->chrUPixBuf[i] = c->chrUPixBuf[i+c->vChrBufSize];

         c->chrVPixBuf[i] = c->chrVPixBuf[i+c->vChrBufSize] = c->chrUPixBuf[i] + (dst_stride >> 1) + 8;

     }
     if (CONFIG_SWSCALE_ALPHA && c->alpPixBuf)
         for (i=0; i<c->vLumBufSize; i++) {

             FF_ALLOCZ_OR_GOTO(c, c->alpPixBuf[i+c->vLumBufSize], dst_stride+16, fail);

             c->alpPixBuf[i] = c->alpPixBuf[i+c->vLumBufSize];
         }
 
     //try to avoid drawing green stuff between the right end and the stride end

     for (i=0; i<c->vChrBufSize; i++)

         if(av_pix_fmt_descriptors[c->dstFormat].comp[0].depth_minus1 == 15){

             av_assert0(c->dstBpc > 10);

             for(j=0; j<dst_stride/2+1; j++)
                 ((int32_t*)(c->chrUPixBuf[i]))[j] = 1<<18;
         } else
             for(j=0; j<dst_stride+1; j++)
                 ((int16_t*)(c->chrUPixBuf[i]))[j] = 1<<14;

 
     assert(c->chrDstH <= dstH);
 
     if (flags&SWS_PRINT_INFO) {

         if      (flags&SWS_FAST_BILINEAR) av_log(c, AV_LOG_INFO, "FAST_BILINEAR scaler, ");
         else if (flags&SWS_BILINEAR)      av_log(c, AV_LOG_INFO, "BILINEAR scaler, ");
         else if (flags&SWS_BICUBIC)       av_log(c, AV_LOG_INFO, "BICUBIC scaler, ");
         else if (flags&SWS_X)             av_log(c, AV_LOG_INFO, "Experimental scaler, ");
         else if (flags&SWS_POINT)         av_log(c, AV_LOG_INFO, "Nearest Neighbor / POINT scaler, ");
         else if (flags&SWS_AREA)          av_log(c, AV_LOG_INFO, "Area Averaging scaler, ");
         else if (flags&SWS_BICUBLIN)      av_log(c, AV_LOG_INFO, "luma BICUBIC / chroma BILINEAR scaler, ");
         else if (flags&SWS_GAUSS)         av_log(c, AV_LOG_INFO, "Gaussian scaler, ");
         else if (flags&SWS_SINC)          av_log(c, AV_LOG_INFO, "Sinc scaler, ");
         else if (flags&SWS_LANCZOS)       av_log(c, AV_LOG_INFO, "Lanczos scaler, ");
         else if (flags&SWS_SPLINE)        av_log(c, AV_LOG_INFO, "Bicubic spline scaler, ");
         else                              av_log(c, AV_LOG_INFO, "ehh flags invalid?! ");

 
         av_log(c, AV_LOG_INFO, "from %s to %s%s ",

                av_get_pix_fmt_name(srcFormat),

 #ifdef DITHER1XBPP

                dstFormat == PIX_FMT_BGR555 || dstFormat == PIX_FMT_BGR565 ||
                dstFormat == PIX_FMT_RGB444BE || dstFormat == PIX_FMT_RGB444LE ||
                dstFormat == PIX_FMT_BGR444BE || dstFormat == PIX_FMT_BGR444LE ? "dithered " : "",

 #else
                "",
 #endif

                av_get_pix_fmt_name(dstFormat));

         if      (HAVE_MMX2     && cpu_flags & AV_CPU_FLAG_MMX2)    av_log(c, AV_LOG_INFO, "using MMX2\n");
         else if (HAVE_AMD3DNOW && cpu_flags & AV_CPU_FLAG_3DNOW)   av_log(c, AV_LOG_INFO, "using 3DNOW\n");
         else if (HAVE_MMX      && cpu_flags & AV_CPU_FLAG_MMX)     av_log(c, AV_LOG_INFO, "using MMX\n");
         else if (HAVE_ALTIVEC  && cpu_flags & AV_CPU_FLAG_ALTIVEC) av_log(c, AV_LOG_INFO, "using AltiVec\n");

         else                                   av_log(c, AV_LOG_INFO, "using C\n");

 
         av_log(c, AV_LOG_VERBOSE, "%dx%d -> %dx%d\n", srcW, srcH, dstW, dstH);
         av_log(c, AV_LOG_DEBUG, "lum srcW=%d srcH=%d dstW=%d dstH=%d xInc=%d yInc=%d\n",
                c->srcW, c->srcH, c->dstW, c->dstH, c->lumXInc, c->lumYInc);
         av_log(c, AV_LOG_DEBUG, "chr srcW=%d srcH=%d dstW=%d dstH=%d xInc=%d yInc=%d\n",
                c->chrSrcW, c->chrSrcH, c->chrDstW, c->chrDstH, c->chrXInc, c->chrYInc);
     }
 
     c->swScale= ff_getSwsFunc(c);

     return 0;
 fail: //FIXME replace things by appropriate error codes
     return -1;
 }

 #if FF_API_SWS_GETCONTEXT

 SwsContext *sws_getContext(int srcW, int srcH, enum PixelFormat srcFormat,
                            int dstW, int dstH, enum PixelFormat dstFormat, int flags,
                            SwsFilter *srcFilter, SwsFilter *dstFilter, const double *param)
 {
     SwsContext *c;
 
     if(!(c=sws_alloc_context()))
         return NULL;
 
     c->flags= flags;
     c->srcW= srcW;
     c->srcH= srcH;
     c->dstW= dstW;
     c->dstH= dstH;
     c->srcRange = handle_jpeg(&srcFormat);
     c->dstRange = handle_jpeg(&dstFormat);
     c->srcFormat= srcFormat;
     c->dstFormat= dstFormat;
 
     if (param) {
         c->param[0] = param[0];
         c->param[1] = param[1];
     }
     sws_setColorspaceDetails(c, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT], c->srcRange, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT] /* FIXME*/, c->dstRange, 0, 1<<16, 1<<16);
 
     if(sws_init_context(c, srcFilter, dstFilter) < 0){
         sws_freeContext(c);
         return NULL;
     }
 
     return c;

 }

 #endif

 
 SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
                                 float lumaSharpen, float chromaSharpen,
                                 float chromaHShift, float chromaVShift,
                                 int verbose)
 {
     SwsFilter *filter= av_malloc(sizeof(SwsFilter));
     if (!filter)
         return NULL;
 
     if (lumaGBlur!=0.0) {
         filter->lumH= sws_getGaussianVec(lumaGBlur, 3.0);
         filter->lumV= sws_getGaussianVec(lumaGBlur, 3.0);
     } else {
         filter->lumH= sws_getIdentityVec();
         filter->lumV= sws_getIdentityVec();
     }
 
     if (chromaGBlur!=0.0) {
         filter->chrH= sws_getGaussianVec(chromaGBlur, 3.0);
         filter->chrV= sws_getGaussianVec(chromaGBlur, 3.0);
     } else {
         filter->chrH= sws_getIdentityVec();
         filter->chrV= sws_getIdentityVec();
     }
 
     if (chromaSharpen!=0.0) {
         SwsVector *id= sws_getIdentityVec();
         sws_scaleVec(filter->chrH, -chromaSharpen);
         sws_scaleVec(filter->chrV, -chromaSharpen);
         sws_addVec(filter->chrH, id);
         sws_addVec(filter->chrV, id);
         sws_freeVec(id);
     }
 
     if (lumaSharpen!=0.0) {
         SwsVector *id= sws_getIdentityVec();
         sws_scaleVec(filter->lumH, -lumaSharpen);
         sws_scaleVec(filter->lumV, -lumaSharpen);
         sws_addVec(filter->lumH, id);
         sws_addVec(filter->lumV, id);
         sws_freeVec(id);
     }
 
     if (chromaHShift != 0.0)
         sws_shiftVec(filter->chrH, (int)(chromaHShift+0.5));
 
     if (chromaVShift != 0.0)
         sws_shiftVec(filter->chrV, (int)(chromaVShift+0.5));
 
     sws_normalizeVec(filter->chrH, 1.0);
     sws_normalizeVec(filter->chrV, 1.0);
     sws_normalizeVec(filter->lumH, 1.0);
     sws_normalizeVec(filter->lumV, 1.0);
 
     if (verbose) sws_printVec2(filter->chrH, NULL, AV_LOG_DEBUG);
     if (verbose) sws_printVec2(filter->lumH, NULL, AV_LOG_DEBUG);
 
     return filter;
 }
 
 SwsVector *sws_allocVec(int length)
 {
     SwsVector *vec = av_malloc(sizeof(SwsVector));
     if (!vec)
         return NULL;
     vec->length = length;
     vec->coeff  = av_malloc(sizeof(double) * length);
     if (!vec->coeff)
         av_freep(&vec);
     return vec;
 }
 
 SwsVector *sws_getGaussianVec(double variance, double quality)
 {
     const int length= (int)(variance*quality + 0.5) | 1;
     int i;
     double middle= (length-1)*0.5;
     SwsVector *vec= sws_allocVec(length);
 
     if (!vec)
         return NULL;
 
     for (i=0; i<length; i++) {
         double dist= i-middle;

         vec->coeff[i]= exp(-dist*dist/(2*variance*variance)) / sqrt(2*variance*M_PI);

     }
 
     sws_normalizeVec(vec, 1.0);
 
     return vec;
 }
 
 SwsVector *sws_getConstVec(double c, int length)
 {
     int i;
     SwsVector *vec= sws_allocVec(length);
 
     if (!vec)
         return NULL;
 
     for (i=0; i<length; i++)
         vec->coeff[i]= c;
 
     return vec;
 }
 
 SwsVector *sws_getIdentityVec(void)
 {
     return sws_getConstVec(1.0, 1);
 }
 

 static double sws_dcVec(SwsVector *a)

 {
     int i;
     double sum=0;
 
     for (i=0; i<a->length; i++)
         sum+= a->coeff[i];
 
     return sum;
 }
 
 void sws_scaleVec(SwsVector *a, double scalar)
 {
     int i;
 
     for (i=0; i<a->length; i++)
         a->coeff[i]*= scalar;
 }
 
 void sws_normalizeVec(SwsVector *a, double height)
 {
     sws_scaleVec(a, height/sws_dcVec(a));
 }
 
 static SwsVector *sws_getConvVec(SwsVector *a, SwsVector *b)
 {
     int length= a->length + b->length - 1;
     int i, j;
     SwsVector *vec= sws_getConstVec(0.0, length);
 
     if (!vec)
         return NULL;
 
     for (i=0; i<a->length; i++) {
         for (j=0; j<b->length; j++) {
             vec->coeff[i+j]+= a->coeff[i]*b->coeff[j];
         }
     }
 
     return vec;
 }
 
 static SwsVector *sws_sumVec(SwsVector *a, SwsVector *b)
 {
     int length= FFMAX(a->length, b->length);
     int i;
     SwsVector *vec= sws_getConstVec(0.0, length);
 
     if (!vec)
         return NULL;
 
     for (i=0; i<a->length; i++) vec->coeff[i + (length-1)/2 - (a->length-1)/2]+= a->coeff[i];
     for (i=0; i<b->length; i++) vec->coeff[i + (length-1)/2 - (b->length-1)/2]+= b->coeff[i];
 
     return vec;
 }
 
 static SwsVector *sws_diffVec(SwsVector *a, SwsVector *b)
 {
     int length= FFMAX(a->length, b->length);
     int i;
     SwsVector *vec= sws_getConstVec(0.0, length);
 
     if (!vec)
         return NULL;
 
     for (i=0; i<a->length; i++) vec->coeff[i + (length-1)/2 - (a->length-1)/2]+= a->coeff[i];
     for (i=0; i<b->length; i++) vec->coeff[i + (length-1)/2 - (b->length-1)/2]-= b->coeff[i];
 
     return vec;
 }
 
 /* shift left / or right if "shift" is negative */
 static SwsVector *sws_getShiftedVec(SwsVector *a, int shift)
 {
     int length= a->length + FFABS(shift)*2;
     int i;
     SwsVector *vec= sws_getConstVec(0.0, length);
 
     if (!vec)
         return NULL;
 
     for (i=0; i<a->length; i++) {
         vec->coeff[i + (length-1)/2 - (a->length-1)/2 - shift]= a->coeff[i];
     }
 
     return vec;
 }
 
 void sws_shiftVec(SwsVector *a, int shift)
 {
     SwsVector *shifted= sws_getShiftedVec(a, shift);
     av_free(a->coeff);
     a->coeff= shifted->coeff;
     a->length= shifted->length;
     av_free(shifted);
 }
 
 void sws_addVec(SwsVector *a, SwsVector *b)
 {
     SwsVector *sum= sws_sumVec(a, b);
     av_free(a->coeff);
     a->coeff= sum->coeff;
     a->length= sum->length;
     av_free(sum);
 }
 
 void sws_subVec(SwsVector *a, SwsVector *b)
 {
     SwsVector *diff= sws_diffVec(a, b);
     av_free(a->coeff);
     a->coeff= diff->coeff;
     a->length= diff->length;
     av_free(diff);
 }
 
 void sws_convVec(SwsVector *a, SwsVector *b)
 {
     SwsVector *conv= sws_getConvVec(a, b);
     av_free(a->coeff);
     a->coeff= conv->coeff;
     a->length= conv->length;
     av_free(conv);
 }
 
 SwsVector *sws_cloneVec(SwsVector *a)
 {
     int i;
     SwsVector *vec= sws_allocVec(a->length);
 
     if (!vec)
         return NULL;
 
     for (i=0; i<a->length; i++) vec->coeff[i]= a->coeff[i];
 
     return vec;
 }
 
 void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level)
 {
     int i;
     double max=0;
     double min=0;
     double range;
 
     for (i=0; i<a->length; i++)
         if (a->coeff[i]>max) max= a->coeff[i];
 
     for (i=0; i<a->length; i++)
         if (a->coeff[i]<min) min= a->coeff[i];
 
     range= max - min;
 
     for (i=0; i<a->length; i++) {
         int x= (int)((a->coeff[i]-min)*60.0/range +0.5);
         av_log(log_ctx, log_level, "%1.3f ", a->coeff[i]);
         for (;x>0; x--) av_log(log_ctx, log_level, " ");
         av_log(log_ctx, log_level, "|\n");
     }
 }
 
 void sws_freeVec(SwsVector *a)
 {
     if (!a) return;
     av_freep(&a->coeff);
     a->length=0;
     av_free(a);
 }
 
 void sws_freeFilter(SwsFilter *filter)
 {
     if (!filter) return;
 
     if (filter->lumH) sws_freeVec(filter->lumH);
     if (filter->lumV) sws_freeVec(filter->lumV);
     if (filter->chrH) sws_freeVec(filter->chrH);
     if (filter->chrV) sws_freeVec(filter->chrV);
     av_free(filter);
 }
 
 void sws_freeContext(SwsContext *c)
 {
     int i;
     if (!c) return;
 
     if (c->lumPixBuf) {
         for (i=0; i<c->vLumBufSize; i++)
             av_freep(&c->lumPixBuf[i]);
         av_freep(&c->lumPixBuf);
     }
 

     if (c->chrUPixBuf) {

         for (i=0; i<c->vChrBufSize; i++)

             av_freep(&c->chrUPixBuf[i]);
         av_freep(&c->chrUPixBuf);
         av_freep(&c->chrVPixBuf);

     }
 
     if (CONFIG_SWSCALE_ALPHA && c->alpPixBuf) {
         for (i=0; i<c->vLumBufSize; i++)
             av_freep(&c->alpPixBuf[i]);
         av_freep(&c->alpPixBuf);
     }
 
     av_freep(&c->vLumFilter);
     av_freep(&c->vChrFilter);
     av_freep(&c->hLumFilter);
     av_freep(&c->hChrFilter);

 #if HAVE_ALTIVEC

     av_freep(&c->vYCoeffsBank);
     av_freep(&c->vCCoeffsBank);
 #endif
 
     av_freep(&c->vLumFilterPos);
     av_freep(&c->vChrFilterPos);
     av_freep(&c->hLumFilterPos);
     av_freep(&c->hChrFilterPos);
 

 #if HAVE_MMX

 #ifdef MAP_ANONYMOUS
     if (c->lumMmx2FilterCode) munmap(c->lumMmx2FilterCode, c->lumMmx2FilterCodeSize);
     if (c->chrMmx2FilterCode) munmap(c->chrMmx2FilterCode, c->chrMmx2FilterCodeSize);
 #elif HAVE_VIRTUALALLOC

     if (c->lumMmx2FilterCode) VirtualFree(c->lumMmx2FilterCode, 0, MEM_RELEASE);
     if (c->chrMmx2FilterCode) VirtualFree(c->chrMmx2FilterCode, 0, MEM_RELEASE);

 #else
     av_free(c->lumMmx2FilterCode);
     av_free(c->chrMmx2FilterCode);
 #endif
     c->lumMmx2FilterCode=NULL;
     c->chrMmx2FilterCode=NULL;

 #endif /* HAVE_MMX */

 
     av_freep(&c->yuvTable);

     av_freep(&c->formatConvBuffer);

 
     av_free(c);
 }
 
 struct SwsContext *sws_getCachedContext(struct SwsContext *context,
                                         int srcW, int srcH, enum PixelFormat srcFormat,
                                         int dstW, int dstH, enum PixelFormat dstFormat, int flags,
                                         SwsFilter *srcFilter, SwsFilter *dstFilter, const double *param)
 {
     static const double default_param[2] = {SWS_PARAM_DEFAULT, SWS_PARAM_DEFAULT};
 
     if (!param)
         param = default_param;
 

     if (context &&

         (context->srcW      != srcW      ||
          context->srcH      != srcH      ||
          context->srcFormat != srcFormat ||
          context->dstW      != dstW      ||
          context->dstH      != dstH      ||
          context->dstFormat != dstFormat ||
          context->flags     != flags     ||
          context->param[0]  != param[0]  ||

          context->param[1]  != param[1])) {
         sws_freeContext(context);
         context = NULL;
     }

     if (!context) {

         if (!(context = sws_alloc_context()))
             return NULL;
         context->srcW      = srcW;
         context->srcH      = srcH;

         context->srcRange  = handle_jpeg(&srcFormat);

         context->srcFormat = srcFormat;

         context->dstW      = dstW;
         context->dstH      = dstH;

         context->dstRange  = handle_jpeg(&dstFormat);

         context->dstFormat = dstFormat;
         context->flags     = flags;
         context->param[0]  = param[0];
         context->param[1]  = param[1];

         sws_setColorspaceDetails(context, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT], context->srcRange, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT] /* FIXME*/, context->dstRange, 0, 1<<16, 1<<16);

         if (sws_init_context(context, srcFilter, dstFilter) < 0) {
             sws_freeContext(context);
             return NULL;
         }

     }
     return context;
 }