PeerStreamer

/*

 * High quality image resampling with polyphase filters

 * Copyright (c) 2001 Fabrice Bellard.

 *

 * This library 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 of the License, or (at your option) any later version.

 *

 * This library 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 this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file imgresample.c

 * High quality image resampling with polyphase filters .

 */

#include "avcodec.h"

#include "dsputil.h"

#ifdef USE_FASTMEMCPY

#include "fastmemcpy.h"

#endif

#define NB_COMPONENTS 3

#define PHASE_BITS 4

#define NB_PHASES  (1 << PHASE_BITS)

#define NB_TAPS    4

#define FCENTER    1  /* index of the center of the filter */

//#define TEST    1  /* Test it */

#define POS_FRAC_BITS 16

#define POS_FRAC      (1 << POS_FRAC_BITS)

/* 6 bits precision is needed for MMX */

#define FILTER_BITS   8

#define LINE_BUF_HEIGHT (NB_TAPS * 4)

struct ImgReSampleContext {

    int iwidth, iheight, owidth, oheight;

    int topBand, bottomBand, leftBand, rightBand;

    int padtop, padbottom, padleft, padright;

    int pad_owidth, pad_oheight;

    int h_incr, v_incr;

    int16_t h_filters[NB_PHASES][NB_TAPS] __align8; /* horizontal filters */

    int16_t v_filters[NB_PHASES][NB_TAPS] __align8; /* vertical filters */

    uint8_t *line_buf;

};

void av_build_filter(int16_t *filter, double factor, int tap_count, int phase_count, int scale, int type);

static inline int get_phase(int pos)

{

    return ((pos) >> (POS_FRAC_BITS - PHASE_BITS)) & ((1 << PHASE_BITS) - 1);

}

/* This function must be optimized */

static void h_resample_fast(uint8_t *dst, int dst_width, const uint8_t *src,

                            int src_width, int src_start, int src_incr,

                            int16_t *filters)

{

    int src_pos, phase, sum, i;

    const uint8_t *s;

    int16_t *filter;

    src_pos = src_start;

    for(i=0;i<dst_width;i++) {

#ifdef TEST

        /* test */

        if ((src_pos >> POS_FRAC_BITS) < 0 ||

            (src_pos >> POS_FRAC_BITS) > (src_width - NB_TAPS))

            av_abort();

#endif

        s = src + (src_pos >> POS_FRAC_BITS);

        phase = get_phase(src_pos);

        filter = filters + phase * NB_TAPS;

#if NB_TAPS == 4

        sum = s[0] * filter[0] +

            s[1] * filter[1] +

            s[2] * filter[2] +

            s[3] * filter[3];

#else

        {

            int j;

            sum = 0;

            for(j=0;j<NB_TAPS;j++)

                sum += s[j] * filter[j];

        }

#endif

        sum = sum >> FILTER_BITS;

        if (sum < 0)

            sum = 0;

        else if (sum > 255)

            sum = 255;

        dst[0] = sum;

        src_pos += src_incr;

        dst++;

    }

}

/* This function must be optimized */

static void v_resample(uint8_t *dst, int dst_width, const uint8_t *src,

                       int wrap, int16_t *filter)

{

    int sum, i;

    const uint8_t *s;

    s = src;

    for(i=0;i<dst_width;i++) {

#if NB_TAPS == 4

        sum = s[0 * wrap] * filter[0] +

            s[1 * wrap] * filter[1] +

            s[2 * wrap] * filter[2] +

            s[3 * wrap] * filter[3];

#else

        {

            int j;

            uint8_t *s1 = s;

            sum = 0;

            for(j=0;j<NB_TAPS;j++) {

                sum += s1[0] * filter[j];

                s1 += wrap;

            }

        }

#endif

        sum = sum >> FILTER_BITS;

        if (sum < 0)

            sum = 0;

        else if (sum > 255)

            sum = 255;

        dst[0] = sum;

        dst++;

        s++;

    }

}

#ifdef HAVE_MMX

#include "i386/mmx.h"

#define FILTER4(reg) \

{\

        s = src + (src_pos >> POS_FRAC_BITS);\

        phase = get_phase(src_pos);\

        filter = filters + phase * NB_TAPS;\

        movq_m2r(*s, reg);\

        punpcklbw_r2r(mm7, reg);\

        movq_m2r(*filter, mm6);\

        pmaddwd_r2r(reg, mm6);\

        movq_r2r(mm6, reg);\

        psrlq_i2r(32, reg);\

        paddd_r2r(mm6, reg);\

        psrad_i2r(FILTER_BITS, reg);\

        src_pos += src_incr;\

}

#define DUMP(reg) movq_r2m(reg, tmp); printf(#reg "=%016Lx\n", tmp.uq);

/* XXX: do four pixels at a time */

static void h_resample_fast4_mmx(uint8_t *dst, int dst_width,

                                 const uint8_t *src, int src_width,

                                 int src_start, int src_incr, int16_t *filters)

{

    int src_pos, phase;

    const uint8_t *s;

    int16_t *filter;

    mmx_t tmp;

    src_pos = src_start;

    pxor_r2r(mm7, mm7);

    while (dst_width >= 4) {

        FILTER4(mm0);

        FILTER4(mm1);

        FILTER4(mm2);

        FILTER4(mm3);

        packuswb_r2r(mm7, mm0);

        packuswb_r2r(mm7, mm1);

        packuswb_r2r(mm7, mm3);

        packuswb_r2r(mm7, mm2);

        movq_r2m(mm0, tmp);

        dst[0] = tmp.ub[0];

        movq_r2m(mm1, tmp);

        dst[1] = tmp.ub[0];

        movq_r2m(mm2, tmp);

        dst[2] = tmp.ub[0];

        movq_r2m(mm3, tmp);

        dst[3] = tmp.ub[0];

        dst += 4;

        dst_width -= 4;

    }

    while (dst_width > 0) {

        FILTER4(mm0);

        packuswb_r2r(mm7, mm0);

        movq_r2m(mm0, tmp);

        dst[0] = tmp.ub[0];

        dst++;

        dst_width--;

    }

    emms();

}

static void v_resample4_mmx(uint8_t *dst, int dst_width, const uint8_t *src,

                            int wrap, int16_t *filter)

{

    int sum, i, v;

    const uint8_t *s;

    mmx_t tmp;

    mmx_t coefs[4];

    for(i=0;i<4;i++) {

        v = filter[i];

        coefs[i].uw[0] = v;

        coefs[i].uw[1] = v;

        coefs[i].uw[2] = v;

        coefs[i].uw[3] = v;

    }

    pxor_r2r(mm7, mm7);

    s = src;

    while (dst_width >= 4) {

        movq_m2r(s[0 * wrap], mm0);

        punpcklbw_r2r(mm7, mm0);

        movq_m2r(s[1 * wrap], mm1);

        punpcklbw_r2r(mm7, mm1);

        movq_m2r(s[2 * wrap], mm2);

        punpcklbw_r2r(mm7, mm2);

        movq_m2r(s[3 * wrap], mm3);

        punpcklbw_r2r(mm7, mm3);

        pmullw_m2r(coefs[0], mm0);

        pmullw_m2r(coefs[1], mm1);

        pmullw_m2r(coefs[2], mm2);

        pmullw_m2r(coefs[3], mm3);

        paddw_r2r(mm1, mm0);

        paddw_r2r(mm3, mm2);

        paddw_r2r(mm2, mm0);

        psraw_i2r(FILTER_BITS, mm0);

        packuswb_r2r(mm7, mm0);

        movq_r2m(mm0, tmp);

        *(uint32_t *)dst = tmp.ud[0];

        dst += 4;

        s += 4;

        dst_width -= 4;

    }

    while (dst_width > 0) {

        sum = s[0 * wrap] * filter[0] +

            s[1 * wrap] * filter[1] +

            s[2 * wrap] * filter[2] +

            s[3 * wrap] * filter[3];

        sum = sum >> FILTER_BITS;

        if (sum < 0)

            sum = 0;

        else if (sum > 255)

            sum = 255;

        dst[0] = sum;

        dst++;

        s++;

        dst_width--;

    }

    emms();

}

#endif

#ifdef HAVE_ALTIVEC

typedef         union {

    vector unsigned char v;

    unsigned char c[16];

} vec_uc_t;

typedef         union {

    vector signed short v;

    signed short s[8];

} vec_ss_t;

void v_resample16_altivec(uint8_t *dst, int dst_width, const uint8_t *src,

                          int wrap, int16_t *filter)

{

    int sum, i;

    const uint8_t *s;

    vector unsigned char *tv, tmp, dstv, zero;

    vec_ss_t srchv[4], srclv[4], fv[4];

    vector signed short zeros, sumhv, sumlv;

    s = src;

    for(i=0;i<4;i++)

    {

        /*

           The vec_madds later on does an implicit >>15 on the result.

           Since FILTER_BITS is 8, and we have 15 bits of magnitude in

           a signed short, we have just enough bits to pre-shift our

           filter constants <<7 to compensate for vec_madds.

        */

        fv[i].s[0] = filter[i] << (15-FILTER_BITS);

        fv[i].v = vec_splat(fv[i].v, 0);

    }

    zero = vec_splat_u8(0);

    zeros = vec_splat_s16(0);

    /*

       When we're resampling, we'd ideally like both our input buffers,

       and output buffers to be 16-byte aligned, so we can do both aligned

       reads and writes. Sadly we can't always have this at the moment, so

       we opt for aligned writes, as unaligned writes have a huge overhead.

       To do this, do enough scalar resamples to get dst 16-byte aligned.

    */

    i = (-(int)dst) & 0xf;

    while(i>0) {

        sum = s[0 * wrap] * filter[0] +

        s[1 * wrap] * filter[1] +

        s[2 * wrap] * filter[2] +

        s[3 * wrap] * filter[3];

        sum = sum >> FILTER_BITS;

        if (sum<0) sum = 0; else if (sum>255) sum=255;

        dst[0] = sum;

        dst++;

        s++;

        dst_width--;

        i--;

    }

    /* Do our altivec resampling on 16 pixels at once. */

    while(dst_width>=16) {

        /*

           Read 16 (potentially unaligned) bytes from each of

           4 lines into 4 vectors, and split them into shorts.

           Interleave the multipy/accumulate for the resample

           filter with the loads to hide the 3 cycle latency

           the vec_madds have.

        */

        tv = (vector unsigned char *) &s[0 * wrap];

        tmp = vec_perm(tv[0], tv[1], vec_lvsl(0, &s[i * wrap]));

        srchv[0].v = (vector signed short) vec_mergeh(zero, tmp);

        srclv[0].v = (vector signed short) vec_mergel(zero, tmp);

        sumhv = vec_madds(srchv[0].v, fv[0].v, zeros);

        sumlv = vec_madds(srclv[0].v, fv[0].v, zeros);

        tv = (vector unsigned char *) &s[1 * wrap];

        tmp = vec_perm(tv[0], tv[1], vec_lvsl(0, &s[1 * wrap]));

        srchv[1].v = (vector signed short) vec_mergeh(zero, tmp);

        srclv[1].v = (vector signed short) vec_mergel(zero, tmp);

        sumhv = vec_madds(srchv[1].v, fv[1].v, sumhv);

        sumlv = vec_madds(srclv[1].v, fv[1].v, sumlv);

        tv = (vector unsigned char *) &s[2 * wrap];

        tmp = vec_perm(tv[0], tv[1], vec_lvsl(0, &s[2 * wrap]));

        srchv[2].v = (vector signed short) vec_mergeh(zero, tmp);

        srclv[2].v = (vector signed short) vec_mergel(zero, tmp);

        sumhv = vec_madds(srchv[2].v, fv[2].v, sumhv);

        sumlv = vec_madds(srclv[2].v, fv[2].v, sumlv);

        tv = (vector unsigned char *) &s[3 * wrap];

        tmp = vec_perm(tv[0], tv[1], vec_lvsl(0, &s[3 * wrap]));

        srchv[3].v = (vector signed short) vec_mergeh(zero, tmp);

        srclv[3].v = (vector signed short) vec_mergel(zero, tmp);

        sumhv = vec_madds(srchv[3].v, fv[3].v, sumhv);

        sumlv = vec_madds(srclv[3].v, fv[3].v, sumlv);

        /*

           Pack the results into our destination vector,

           and do an aligned write of that back to memory.

        */

        dstv = vec_packsu(sumhv, sumlv) ;

        vec_st(dstv, 0, (vector unsigned char *) dst);

        dst+=16;

        s+=16;

        dst_width-=16;

    }

    /*

       If there are any leftover pixels, resample them

       with the slow scalar method.

    */

    while(dst_width>0) {

        sum = s[0 * wrap] * filter[0] +

        s[1 * wrap] * filter[1] +

        s[2 * wrap] * filter[2] +

        s[3 * wrap] * filter[3];

        sum = sum >> FILTER_BITS;

        if (sum<0) sum = 0; else if (sum>255) sum=255;

        dst[0] = sum;

        dst++;

        s++;

        dst_width--;

    }

}

#endif

/* slow version to handle limit cases. Does not need optimisation */

static void h_resample_slow(uint8_t *dst, int dst_width,

                            const uint8_t *src, int src_width,

                            int src_start, int src_incr, int16_t *filters)

{

    int src_pos, phase, sum, j, v, i;

    const uint8_t *s, *src_end;

    int16_t *filter;

    src_end = src + src_width;

    src_pos = src_start;

    for(i=0;i<dst_width;i++) {

        s = src + (src_pos >> POS_FRAC_BITS);

        phase = get_phase(src_pos);

        filter = filters + phase * NB_TAPS;

        sum = 0;

        for(j=0;j<NB_TAPS;j++) {

            if (s < src)

                v = src[0];

            else if (s >= src_end)

                v = src_end[-1];

            else

                v = s[0];

            sum += v * filter[j];

            s++;

        }

        sum = sum >> FILTER_BITS;

        if (sum < 0)

            sum = 0;

        else if (sum > 255)

            sum = 255;

        dst[0] = sum;

        src_pos += src_incr;

        dst++;

    }

}

static void h_resample(uint8_t *dst, int dst_width, const uint8_t *src,

                       int src_width, int src_start, int src_incr,

                       int16_t *filters)

{

    int n, src_end;

    if (src_start < 0) {

        n = (0 - src_start + src_incr - 1) / src_incr;

        h_resample_slow(dst, n, src, src_width, src_start, src_incr, filters);

        dst += n;

        dst_width -= n;

        src_start += n * src_incr;

    }

    src_end = src_start + dst_width * src_incr;

    if (src_end > ((src_width - NB_TAPS) << POS_FRAC_BITS)) {

        n = (((src_width - NB_TAPS + 1) << POS_FRAC_BITS) - 1 - src_start) /

            src_incr;

    } else {

        n = dst_width;

    }

#ifdef HAVE_MMX

    if ((mm_flags & MM_MMX) && NB_TAPS == 4)

        h_resample_fast4_mmx(dst, n,

                             src, src_width, src_start, src_incr, filters);

    else

#endif

        h_resample_fast(dst, n,

                        src, src_width, src_start, src_incr, filters);

    if (n < dst_width) {

        dst += n;

        dst_width -= n;

        src_start += n * src_incr;

        h_resample_slow(dst, dst_width,

                        src, src_width, src_start, src_incr, filters);

    }

}

static void component_resample(ImgReSampleContext *s,

                               uint8_t *output, int owrap, int owidth, int oheight,

                               uint8_t *input, int iwrap, int iwidth, int iheight)

{

    int src_y, src_y1, last_src_y, ring_y, phase_y, y1, y;

    uint8_t *new_line, *src_line;

    last_src_y = - FCENTER - 1;

    /* position of the bottom of the filter in the source image */

    src_y = (last_src_y + NB_TAPS) * POS_FRAC;

    ring_y = NB_TAPS; /* position in ring buffer */

    for(y=0;y<oheight;y++) {

        /* apply horizontal filter on new lines from input if needed */

        src_y1 = src_y >> POS_FRAC_BITS;

        while (last_src_y < src_y1) {

            if (++ring_y >= LINE_BUF_HEIGHT + NB_TAPS)

                ring_y = NB_TAPS;

            last_src_y++;

            /* handle limit conditions : replicate line (slightly

               inefficient because we filter multiple times) */

            y1 = last_src_y;

            if (y1 < 0) {

                y1 = 0;

            } else if (y1 >= iheight) {

                y1 = iheight - 1;

            }

            src_line = input + y1 * iwrap;

            new_line = s->line_buf + ring_y * owidth;

            /* apply filter and handle limit cases correctly */

            h_resample(new_line, owidth,

                       src_line, iwidth, - FCENTER * POS_FRAC, s->h_incr,

                       &s->h_filters[0][0]);

            /* handle ring buffer wraping */

            if (ring_y >= LINE_BUF_HEIGHT) {

                memcpy(s->line_buf + (ring_y - LINE_BUF_HEIGHT) * owidth,

                       new_line, owidth);

            }

        }

        /* apply vertical filter */

        phase_y = get_phase(src_y);

#ifdef HAVE_MMX

        /* desactivated MMX because loss of precision */

        if ((mm_flags & MM_MMX) && NB_TAPS == 4 && 0)

            v_resample4_mmx(output, owidth,

                            s->line_buf + (ring_y - NB_TAPS + 1) * owidth, owidth,

                            &s->v_filters[phase_y][0]);

        else

#endif

#ifdef HAVE_ALTIVEC

            if ((mm_flags & MM_ALTIVEC) && NB_TAPS == 4 && FILTER_BITS <= 6)

                v_resample16_altivec(output, owidth,

                                s->line_buf + (ring_y - NB_TAPS + 1) * owidth, owidth,

                                &s->v_filters[phase_y][0]);

        else

#endif

            v_resample(output, owidth,

                       s->line_buf + (ring_y - NB_TAPS + 1) * owidth, owidth,

                       &s->v_filters[phase_y][0]);

        src_y += s->v_incr;

        output += owrap;

    }

}

ImgReSampleContext *img_resample_init(int owidth, int oheight,

                                      int iwidth, int iheight)

{

    return img_resample_full_init(owidth, oheight, iwidth, iheight,

            0, 0, 0, 0, 0, 0, 0, 0);

}

ImgReSampleContext *img_resample_full_init(int owidth, int oheight,

                                      int iwidth, int iheight,

                                      int topBand, int bottomBand,

        int leftBand, int rightBand,

        int padtop, int padbottom,

        int padleft, int padright)

{

    ImgReSampleContext *s;

    if (!owidth || !oheight || !iwidth || !iheight)

        return NULL;

    s = av_mallocz(sizeof(ImgReSampleContext));

    if (!s)

        return NULL;

    if((unsigned)owidth >= UINT_MAX / (LINE_BUF_HEIGHT + NB_TAPS))

        return NULL;

    s->line_buf = av_mallocz(owidth * (LINE_BUF_HEIGHT + NB_TAPS));

    if (!s->line_buf)

        goto fail;

    s->owidth = owidth;

    s->oheight = oheight;

    s->iwidth = iwidth;

    s->iheight = iheight;

    s->topBand = topBand;

    s->bottomBand = bottomBand;

    s->leftBand = leftBand;

    s->rightBand = rightBand;

    s->padtop = padtop;

    s->padbottom = padbottom;

    s->padleft = padleft;

    s->padright = padright;

    s->pad_owidth = owidth - (padleft + padright);

    s->pad_oheight = oheight - (padtop + padbottom);

    s->h_incr = ((iwidth - leftBand - rightBand) * POS_FRAC) / s->pad_owidth;

    s->v_incr = ((iheight - topBand - bottomBand) * POS_FRAC) / s->pad_oheight;

    av_build_filter(&s->h_filters[0][0], (float) s->pad_owidth  /

            (float) (iwidth - leftBand - rightBand), NB_TAPS, NB_PHASES, 1<<FILTER_BITS, 0);

    av_build_filter(&s->v_filters[0][0], (float) s->pad_oheight /

            (float) (iheight - topBand - bottomBand), NB_TAPS, NB_PHASES, 1<<FILTER_BITS, 0);

    return s;

fail:

    av_free(s);

    return NULL;

}

void img_resample(ImgReSampleContext *s,

                  AVPicture *output, const AVPicture *input)

{

    int i, shift;

    uint8_t* optr;

    for (i=0;i<3;i++) {

        shift = (i == 0) ? 0 : 1;

        optr = output->data[i] + (((output->linesize[i] *

                        s->padtop) + s->padleft) >> shift);

        component_resample(s, optr, output->linesize[i],

                s->pad_owidth >> shift, s->pad_oheight >> shift,

                input->data[i] + (input->linesize[i] *

                    (s->topBand >> shift)) + (s->leftBand >> shift),

                input->linesize[i], ((s->iwidth - s->leftBand -

                        s->rightBand) >> shift),

                           (s->iheight - s->topBand - s->bottomBand) >> shift);

    }

}

void img_resample_close(ImgReSampleContext *s)

{

    av_free(s->line_buf);

    av_free(s);

}

#ifdef TEST

#include <stdio.h>

/* input */

#define XSIZE 256

#define YSIZE 256

uint8_t img[XSIZE * YSIZE];

/* output */

#define XSIZE1 512

#define YSIZE1 512

uint8_t img1[XSIZE1 * YSIZE1];

uint8_t img2[XSIZE1 * YSIZE1];

void save_pgm(const char *filename, uint8_t *img, int xsize, int ysize)

{

#undef fprintf

    FILE *f;

    f=fopen(filename,"w");

    fprintf(f,"P5\n%d %d\n%d\n", xsize, ysize, 255);

    fwrite(img,1, xsize * ysize,f);

    fclose(f);

#define fprintf please_use_av_log

}

static void dump_filter(int16_t *filter)

{

    int i, ph;

    for(ph=0;ph<NB_PHASES;ph++) {

        av_log(NULL, AV_LOG_INFO, "%2d: ", ph);

        for(i=0;i<NB_TAPS;i++) {

            av_log(NULL, AV_LOG_INFO, " %5.2f", filter[ph * NB_TAPS + i] / 256.0);

        }

        av_log(NULL, AV_LOG_INFO, "\n");

    }

}

#ifdef HAVE_MMX

int mm_flags;

#endif

int main(int argc, char **argv)

{

    int x, y, v, i, xsize, ysize;

    ImgReSampleContext *s;

    float fact, factors[] = { 1/2.0, 3.0/4.0, 1.0, 4.0/3.0, 16.0/9.0, 2.0 };

    char buf[256];

    /* build test image */

    for(y=0;y<YSIZE;y++) {

        for(x=0;x<XSIZE;x++) {

            if (x < XSIZE/2 && y < YSIZE/2) {

                if (x < XSIZE/4 && y < YSIZE/4) {

                    if ((x % 10) <= 6 &&

                        (y % 10) <= 6)

                        v = 0xff;

                    else

                        v = 0x00;

                } else if (x < XSIZE/4) {

                    if (x & 1)

                        v = 0xff;

                    else

                        v = 0;

                } else if (y < XSIZE/4) {

                    if (y & 1)

                        v = 0xff;

                    else

                        v = 0;

                } else {

                    if (y < YSIZE*3/8) {

                        if ((y+x) & 1)

                            v = 0xff;

                        else

                            v = 0;

                    } else {

                        if (((x+3) % 4) <= 1 &&

                            ((y+3) % 4) <= 1)

                            v = 0xff;

                        else

                            v = 0x00;

                    }

                }

            } else if (x < XSIZE/2) {

                v = ((x - (XSIZE/2)) * 255) / (XSIZE/2);

            } else if (y < XSIZE/2) {

                v = ((y - (XSIZE/2)) * 255) / (XSIZE/2);

            } else {

                v = ((x + y - XSIZE) * 255) / XSIZE;

            }

            img[(YSIZE - y) * XSIZE + (XSIZE - x)] = v;

        }

    }

    save_pgm("/tmp/in.pgm", img, XSIZE, YSIZE);

    for(i=0;i<sizeof(factors)/sizeof(float);i++) {

        fact = factors[i];

        xsize = (int)(XSIZE * fact);

        ysize = (int)((YSIZE - 100) * fact);

        s = img_resample_full_init(xsize, ysize, XSIZE, YSIZE, 50 ,50, 0, 0, 0, 0, 0, 0);

        av_log(NULL, AV_LOG_INFO, "Factor=%0.2f\n", fact);

        dump_filter(&s->h_filters[0][0]);

        component_resample(s, img1, xsize, xsize, ysize,

                           img + 50 * XSIZE, XSIZE, XSIZE, YSIZE - 100);

        img_resample_close(s);

        snprintf(buf, sizeof(buf), "/tmp/out%d.pgm", i);

        save_pgm(buf, img1, xsize, ysize);

    }

    /* mmx test */

#ifdef HAVE_MMX

    av_log(NULL, AV_LOG_INFO, "MMX test\n");

    fact = 0.72;

    xsize = (int)(XSIZE * fact);

    ysize = (int)(YSIZE * fact);

    mm_flags = MM_MMX;

    s = img_resample_init(xsize, ysize, XSIZE, YSIZE);

    component_resample(s, img1, xsize, xsize, ysize,

                       img, XSIZE, XSIZE, YSIZE);

    mm_flags = 0;

    s = img_resample_init(xsize, ysize, XSIZE, YSIZE);

    component_resample(s, img2, xsize, xsize, ysize,

                       img, XSIZE, XSIZE, YSIZE);

    if (memcmp(img1, img2, xsize * ysize) != 0) {

        av_log(NULL, AV_LOG_ERROR, "mmx error\n");

        exit(1);

    }

    av_log(NULL, AV_LOG_INFO, "MMX OK\n");

#endif

    return 0;

}

#endif