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  • /*
     * 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 General Public License as published by
     * the Free Software Foundation; either version 2 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 General Public License for more details.
     *
     * You should have received a copy of the GNU 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
     *
     * the C code (not assembly, mmx, ...) of this file can be used
     * under the LGPL license too
     */
    
    #define _SVID_SOURCE //needed for MAP_ANONYMOUS
    #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/avutil.h"
    #include "libavutil/bswap.h"
    #include "libavutil/pixdesc.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
    
    #define isSupportedIn(x)    (       \
               (x)==PIX_FMT_YUV420P     \
            || (x)==PIX_FMT_YUVA420P    \
            || (x)==PIX_FMT_YUYV422     \
            || (x)==PIX_FMT_UYVY422     \
            || (x)==PIX_FMT_RGB48BE     \
            || (x)==PIX_FMT_RGB48LE     \
            || (x)==PIX_FMT_RGB32       \
            || (x)==PIX_FMT_RGB32_1     \
            || (x)==PIX_FMT_BGR24       \
            || (x)==PIX_FMT_BGR565      \
            || (x)==PIX_FMT_BGR555      \
            || (x)==PIX_FMT_BGR32       \
            || (x)==PIX_FMT_BGR32_1     \
            || (x)==PIX_FMT_RGB24       \
            || (x)==PIX_FMT_RGB565      \
            || (x)==PIX_FMT_RGB555      \
            || (x)==PIX_FMT_GRAY8       \
            || (x)==PIX_FMT_YUV410P     \
            || (x)==PIX_FMT_YUV440P     \
            || (x)==PIX_FMT_NV12        \
            || (x)==PIX_FMT_NV21        \
            || (x)==PIX_FMT_GRAY16BE    \
            || (x)==PIX_FMT_GRAY16LE    \
            || (x)==PIX_FMT_YUV444P     \
            || (x)==PIX_FMT_YUV422P     \
            || (x)==PIX_FMT_YUV411P     \
            || (x)==PIX_FMT_PAL8        \
            || (x)==PIX_FMT_BGR8        \
            || (x)==PIX_FMT_RGB8        \
            || (x)==PIX_FMT_BGR4_BYTE   \
            || (x)==PIX_FMT_RGB4_BYTE   \
            || (x)==PIX_FMT_YUV440P     \
            || (x)==PIX_FMT_MONOWHITE   \
            || (x)==PIX_FMT_MONOBLACK   \
            || (x)==PIX_FMT_YUV420P16LE   \
            || (x)==PIX_FMT_YUV422P16LE   \
            || (x)==PIX_FMT_YUV444P16LE   \
            || (x)==PIX_FMT_YUV420P16BE   \
            || (x)==PIX_FMT_YUV422P16BE   \
            || (x)==PIX_FMT_YUV444P16BE   \
        )
    
    int sws_isSupportedInput(enum PixelFormat pix_fmt)
    {
        return isSupportedIn(pix_fmt);
    }
    
    #define isSupportedOut(x)   (       \
               (x)==PIX_FMT_YUV420P     \
            || (x)==PIX_FMT_YUVA420P    \
            || (x)==PIX_FMT_YUYV422     \
            || (x)==PIX_FMT_UYVY422     \
            || (x)==PIX_FMT_YUV444P     \
            || (x)==PIX_FMT_YUV422P     \
            || (x)==PIX_FMT_YUV411P     \
            || isRGB(x)                 \
            || isBGR(x)                 \
            || (x)==PIX_FMT_NV12        \
            || (x)==PIX_FMT_NV21        \
            || (x)==PIX_FMT_GRAY16BE    \
            || (x)==PIX_FMT_GRAY16LE    \
            || (x)==PIX_FMT_GRAY8       \
            || (x)==PIX_FMT_YUV410P     \
            || (x)==PIX_FMT_YUV440P     \
            || (x)==PIX_FMT_YUV420P16LE   \
            || (x)==PIX_FMT_YUV422P16LE   \
            || (x)==PIX_FMT_YUV444P16LE   \
            || (x)==PIX_FMT_YUV420P16BE   \
            || (x)==PIX_FMT_YUV422P16BE   \
            || (x)==PIX_FMT_YUV444P16BE   \
        )
    
    int sws_isSupportedOutput(enum PixelFormat pix_fmt)
    {
        return isSupportedOut(pix_fmt);
    }
    
    #define usePal(x) (av_pix_fmt_descriptors[x].flags & PIX_FMT_PAL)
    
    extern const int32_t ff_yuv2rgb_coeffs[8][4];
    
    const char *sws_format_name(enum PixelFormat format)
    {
        if ((unsigned)format < PIX_FMT_NB && av_pix_fmt_descriptors[format].name)
            return av_pix_fmt_descriptors[format].name;
        else
            return "Unknown format";
    }
    
    static double getSplineCoeff(double a, double b, double c, double d, double dist)
    {
    //    printf("%f %f %f %f %f\n", a,b,c,d,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,
                          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;
    #if ARCH_X86
        if (flags & SWS_CPU_CAPS_MMX)
            __asm__ volatile("emms\n\t"::: "memory"); //FIXME this should not be required but it IS (even for non-MMX versions)
    #endif
    
        // NOTE: the +1 is for the MMX scaler which reads over the end
        FF_ALLOC_OR_GOTO(NULL, *filterPos, (dstW+1)*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;
            int 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;
            int 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((xx<<16) - xDstInSrc)*(fone>>16);
                    if (coeff<0) coeff=0;
                    filter[i*filterSize + j]= coeff;
                    xx++;
                }
                xDstInSrc+= xInc;
            }
        } else {
            int 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= ((int64_t)FFABS((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);
                        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 if (d < 1LL<<31)
                            coeff = (-B-6*C)*ddd + (6*B+30*C)*dd + (-12*B-48*C)*d + (8*B+24*C)*(1<<30);
                        else
                            coeff=0.0;
                        coeff *= fone>>(30+24);
                    }
    /*                else if (flags & SWS_X) {
                        double p= param ? param*0.01 : 0.3;
                        coeff = d ? sin(d*PI)/(d*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)
    
                        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;
    
    316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000
                        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 (flags & SWS_CPU_CAPS_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 (flags & SWS_CPU_CAPS_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+1)*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]= (*filterPos)[dstW-1]; // the MMX scaler will read over the end
        for (i=0; i<*outFilterSize; i++) {
            int j= dstW*(*outFilterSize);
            (*outFilter)[j + i]= (*outFilter)[j + i - (*outFilterSize)];
        }
    
        ret=0;
    fail:
        av_free(filter);
        av_free(filter2);
        return ret;
    }
    
    #if ARCH_X86 && (HAVE_MMX2 || CONFIG_RUNTIME_CPUDETECT) && CONFIG_GPL
    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 /* ARCH_X86 && (HAVE_MMX2 || CONFIG_RUNTIME_CPUDETECT) && CONFIG_GPL */
    
    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;
    }
    
    static uint16_t roundToInt16(int64_t f)
    {
        int r= (f + (1<<15))>>16;
             if (r<-0x7FFF) return 0x8000;
        else if (r> 0x7FFF) return 0x7FFF;
        else                return r;
    }
    
    int sws_setColorspaceDetails(SwsContext *c, const int inv_table[4], int srcRange, const int table[4], int dstRange, int brightness, int contrast, int saturation)
    {
        int64_t crv =  inv_table[0];
        int64_t cbu =  inv_table[1];
        int64_t cgu = -inv_table[2];
        int64_t cgv = -inv_table[3];
        int64_t cy  = 1<<16;
        int64_t oy  = 0;
    
        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->uOffset=   0x0400040004000400LL;
        c->vOffset=   0x0400040004000400LL;
    
        if (!srcRange) {
            cy= (cy*255) / 219;
            oy= 16<<16;
        } else {
            crv= (crv*224) / 255;
            cbu= (cbu*224) / 255;
            cgu= (cgu*224) / 255;
            cgv= (cgv*224) / 255;
        }
    
        cy = (cy *contrast             )>>16;
        crv= (crv*contrast * saturation)>>32;
        cbu= (cbu*contrast * saturation)>>32;
        cgu= (cgu*contrast * saturation)>>32;
        cgv= (cgv*contrast * saturation)>>32;
    
        oy -= 256*brightness;
    
        c->yCoeff=    roundToInt16(cy *8192) * 0x0001000100010001ULL;
        c->vrCoeff=   roundToInt16(crv*8192) * 0x0001000100010001ULL;
        c->ubCoeff=   roundToInt16(cbu*8192) * 0x0001000100010001ULL;
        c->vgCoeff=   roundToInt16(cgv*8192) * 0x0001000100010001ULL;
        c->ugCoeff=   roundToInt16(cgu*8192) * 0x0001000100010001ULL;
        c->yOffset=   roundToInt16(oy *   8) * 0x0001000100010001ULL;
    
        c->yuv2rgb_y_coeff  = (int16_t)roundToInt16(cy <<13);
        c->yuv2rgb_y_offset = (int16_t)roundToInt16(oy << 9);
        c->yuv2rgb_v2r_coeff= (int16_t)roundToInt16(crv<<13);
        c->yuv2rgb_v2g_coeff= (int16_t)roundToInt16(cgv<<13);
        c->yuv2rgb_u2g_coeff= (int16_t)roundToInt16(cgu<<13);
        c->yuv2rgb_u2b_coeff= (int16_t)roundToInt16(cbu<<13);
    
        ff_yuv2rgb_c_init_tables(c, inv_table, srcRange, brightness, contrast, saturation);
        //FIXME factorize
    
    #if ARCH_PPC && (HAVE_ALTIVEC || CONFIG_RUNTIME_CPUDETECT)
        if (c->flags & SWS_CPU_CAPS_ALTIVEC)
            ff_yuv2rgb_init_tables_altivec(c, inv_table, brightness, contrast, saturation);
    #endif
        return 0;
    }
    
    int sws_getColorspaceDetails(SwsContext *c, int **inv_table, int *srcRange, int **table, int *dstRange, int *brightness, int *contrast, int *saturation)
    {
        if (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;
        default:
            return 0;
        }
    }
    
    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;
        int i;
        int usesVFilter, usesHFilter;
        int unscaled;
        int srcRange, dstRange;
        SwsFilter dummyFilter= {NULL, NULL, NULL, NULL};
    #if ARCH_X86
        if (flags & SWS_CPU_CAPS_MMX)
            __asm__ volatile("emms\n\t"::: "memory");
    #endif
    
    #if !CONFIG_RUNTIME_CPUDETECT //ensure that the flags match the compiled variant if cpudetect is off
        flags &= ~(SWS_CPU_CAPS_MMX|SWS_CPU_CAPS_MMX2|SWS_CPU_CAPS_3DNOW|SWS_CPU_CAPS_ALTIVEC|SWS_CPU_CAPS_BFIN);
        flags |= ff_hardcodedcpuflags();
    #endif /* CONFIG_RUNTIME_CPUDETECT */
        if (!rgb15to16) sws_rgb2rgb_init(flags);
    
        unscaled = (srcW == dstW && srcH == dstH);
    
        srcRange = handle_jpeg(&srcFormat);
        dstRange = handle_jpeg(&dstFormat);
    
        if (!isSupportedIn(srcFormat)) {
            av_log(NULL, AV_LOG_ERROR, "swScaler: %s is not supported as input pixel format\n", sws_format_name(srcFormat));
            return NULL;
        }
        if (!isSupportedOut(dstFormat)) {
            av_log(NULL, AV_LOG_ERROR, "swScaler: %s is not supported as output pixel format\n", sws_format_name(dstFormat));
            return NULL;
        }
    
        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(NULL, AV_LOG_ERROR, "swScaler: Exactly one scaler algorithm must be chosen\n");
            return NULL;
        }
    
        /* 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(NULL, AV_LOG_ERROR, "swScaler: %dx%d -> %dx%d is invalid scaling dimension\n",
                   srcW, srcH, dstW, dstH);
            return NULL;
        }
        if(srcW > VOFW || dstW > VOFW) {
            av_log(NULL, AV_LOG_ERROR, "swScaler: Compile-time maximum width is "AV_STRINGIFY(VOFW)" change VOF/VOFW and recompile\n");
            return NULL;
        }
    
        if (!dstFilter) dstFilter= &dummyFilter;
        if (!srcFilter) srcFilter= &dummyFilter;
    
        FF_ALLOCZ_OR_GOTO(NULL, c, sizeof(SwsContext), fail);
    
        c->av_class = &sws_context_class;
        c->srcW= srcW;
        c->srcH= srcH;
        c->dstW= dstW;
        c->dstH= dstH;
        c->lumXInc= ((srcW<<16) + (dstW>>1))/dstW;
        c->lumYInc= ((srcH<<16) + (dstH>>1))/dstH;
        c->flags= flags;
        c->dstFormat= dstFormat;
        c->srcFormat= srcFormat;
        c->vRounder= 4* 0x0001000100010001ULL;
    
        usesHFilter= usesVFilter= 0;
        if (dstFilter->lumV && dstFilter->lumV->length>1) usesVFilter=1;
        if (dstFilter->lumH && dstFilter->lumH->length>1) usesHFilter=1;
        if (dstFilter->chrV && dstFilter->chrV->length>1) usesVFilter=1;
        if (dstFilter->chrH && dstFilter->chrH->length>1) usesHFilter=1;
        if (srcFilter->lumV && srcFilter->lumV->length>1) usesVFilter=1;
        if (srcFilter->lumH && srcFilter->lumH->length>1) usesHFilter=1;
        if (srcFilter->chrV && srcFilter->chrV->length>1) usesVFilter=1;
        if (srcFilter->chrH && srcFilter->chrH->length>1) usesHFilter=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 ((isBGR(dstFormat) || isRGB(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 ((isBGR(srcFormat) || isRGB(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|SWS_POINT))))
            c->chrSrcHSubSample=1;
    
        if (param) {
            c->param[0] = param[0];
            c->param[1] = param[1];
        } else {
            c->param[0] =
            c->param[1] = SWS_PARAM_DEFAULT;
        }
    
        // 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);
    
        sws_setColorspaceDetails(c, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT], srcRange, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT] /* FIXME*/, dstRange, 0, 1<<16, 1<<16);
    
        /* unscaled special cases */
        if (unscaled && !usesHFilter && !usesVFilter && (srcRange == dstRange || isBGR(dstFormat) || isRGB(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",
                           sws_format_name(srcFormat), sws_format_name(dstFormat));
                return c;
            }
        }
    
        if (flags & SWS_CPU_CAPS_MMX2) {
            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) 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 (flags & SWS_CPU_CAPS_MMX) {
                c->lumXInc = ((srcW-2)<<16)/(dstW-2) - 20;
                c->chrXInc = ((c->chrSrcW-2)<<16)/(c->chrDstW-2) - 20;
            }
        }
    
        /* precalculate horizontal scaler filter coefficients */
        {
    #if ARCH_X86 && (HAVE_MMX2 || CONFIG_RUNTIME_CPUDETECT) && CONFIG_GPL
    // 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, 0, 0);
                c->chrMmx2FilterCode = mmap(NULL, c->chrMmx2FilterCodeSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 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
    
                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, c->hLumFilterPos, 8);
                initMMX2HScaler(c->chrDstW, c->chrXInc, c->chrMmx2FilterCode, c->hChrFilter, 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 /* ARCH_X86 && (HAVE_MMX2 || CONFIG_RUNTIME_CPUDETECT) && CONFIG_GPL */
            {
                const int filterAlign=
                    (flags & SWS_CPU_CAPS_MMX) ? 4 :
                    (flags & SWS_CPU_CAPS_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,
                               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,
                               srcFilter->chrH, dstFilter->chrH, c->param) < 0)
                    goto fail;
            }
        } // initialize horizontal stuff
    
        /* precalculate vertical scaler filter coefficients */
        {