[deb_ffmpeg.git] / ffmpeg / libavfilter / vf_xbr.c

/*
 * This file is part of FFmpeg.
 *
 * Copyright (c) 2011, 2012 Hyllian/Jararaca <sergiogdb@gmail.com>
 * Copyright (c) 2014 Arwa Arif <arwaarif1994@gmail.com>
 *
 * 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
 */

/**
 * @file
 * XBR Filter is used for depixelization of image.
 * This is based on Hyllian's xBR shader.
 *
 * @see http://www.libretro.com/forums/viewtopic.php?f=6&t=134
 * @see https://github.com/yoyofr/iFBA/blob/master/fba_src/src/intf/video/scalers/xbr.cpp
 */

#include "libavutil/opt.h"
#include "libavutil/avassert.h"
#include "libavutil/pixdesc.h"
#include "internal.h"

#define RGB_MASK      0x00FFFFFF
#define LB_MASK       0x00FEFEFE
#define RED_BLUE_MASK 0x00FF00FF
#define GREEN_MASK    0x0000FF00

typedef int (*xbrfunc_t)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);

typedef struct {
    const AVClass *class;
    int n;
    xbrfunc_t func;
    uint32_t rgbtoyuv[1<<24];
} XBRContext;

typedef struct ThreadData {
    AVFrame *in, *out;
    const uint32_t *rgbtoyuv;
} ThreadData;

#define OFFSET(x) offsetof(XBRContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption xbr_options[] = {
    { "n", "set scale factor", OFFSET(n), AV_OPT_TYPE_INT, {.i64 = 3}, 2, 4, .flags = FLAGS },
    { NULL }
};

AVFILTER_DEFINE_CLASS(xbr);

static uint32_t pixel_diff(uint32_t x, uint32_t y, const uint32_t *r2y)
{
#define YMASK 0xff0000
#define UMASK 0x00ff00
#define VMASK 0x0000ff

    uint32_t yuv1 = r2y[x & 0xffffff];
    uint32_t yuv2 = r2y[y & 0xffffff];

    return (abs((yuv1 & YMASK) - (yuv2 & YMASK)) >> 16) +
           (abs((yuv1 & UMASK) - (yuv2 & UMASK)) >>  8) +
           abs((yuv1 & VMASK) - (yuv2 & VMASK));
}

#define ALPHA_BLEND_128_W(dst, src) dst = ((src & LB_MASK) >> 1) + ((dst & LB_MASK) >> 1)

#define ALPHA_BLEND_32_W(dst, src) \
    dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
          (dst & RED_BLUE_MASK))) >> 3))) | (GREEN_MASK & ((dst & GREEN_MASK) + \
          ((((src & GREEN_MASK) - (dst & GREEN_MASK))) >> 3))))

#define ALPHA_BLEND_64_W(dst, src) \
    dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
          (dst & RED_BLUE_MASK))) >> 2))) | (GREEN_MASK & ((dst & GREEN_MASK) + \
          ((((src & GREEN_MASK) - (dst & GREEN_MASK))) >> 2))))

#define ALPHA_BLEND_192_W(dst, src) \
    dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
          (dst & RED_BLUE_MASK)) * 3) >> 2))) | (GREEN_MASK & ((dst & GREEN_MASK) + \
          ((((src & GREEN_MASK) - (dst & GREEN_MASK)) * 3) >> 2))))

#define ALPHA_BLEND_224_W(dst, src) \
    dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
          (dst & RED_BLUE_MASK)) * 7) >> 3))) | (GREEN_MASK & ((dst & GREEN_MASK) + \
          ((((src & GREEN_MASK) - (dst & GREEN_MASK)) * 7) >> 3))))

#define df(A, B) pixel_diff(A, B, r2y)
#define eq(A, B) (df(A, B) < 155)

#define FILT2(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1,   \
              N0, N1, N2, N3) do {                                                                  \
    if (PE != PH && PE != PF) {                                                                     \
        const unsigned e = df(PE,PC) + df(PE,PG) + df(PI,H5) + df(PI,F4) + (df(PH,PF)<<2);          \
        const unsigned i = df(PH,PD) + df(PH,I5) + df(PF,I4) + df(PF,PB) + (df(PE,PI)<<2);          \
        if (e < i && (!eq(PF,PB) && !eq(PH,PD) || eq(PE,PI)                                         \
                      && (!eq(PF,I4) && !eq(PH,I5))                                                 \
                      || eq(PE,PG) || eq(PE,PC))) {                                                 \
            const unsigned ke = df(PF,PG);                                                          \
            const unsigned ki = df(PH,PC);                                                          \
            const int left    = ke<<1 <= ki && PE != PG && PD != PG;                                \
            const int up      = ke >= ki<<1 && PE != PC && PB != PC;                                \
            const unsigned px = df(PE,PF) <= df(PE,PH) ? PF : PH;                                   \
            if (left && up) {                                                                       \
                ALPHA_BLEND_224_W(E[N3], px);                                                       \
                ALPHA_BLEND_64_W( E[N2], px);                                                       \
                E[N1] = E[N2];                                                                      \
            } else if (left) {                                                                      \
                ALPHA_BLEND_192_W(E[N3], px);                                                       \
                ALPHA_BLEND_64_W( E[N2], px);                                                       \
            } else if (up) {                                                                        \
                ALPHA_BLEND_192_W(E[N3], px);                                                       \
                ALPHA_BLEND_64_W( E[N1], px);                                                       \
            } else { /* diagonal */                                                                 \
                ALPHA_BLEND_128_W(E[N3], px);                                                       \
            }                                                                                       \
        } else if (e <= i) {                                                                        \
            ALPHA_BLEND_128_W( E[N3], ((df(PE,PF) <= df(PE,PH)) ? PF : PH));                        \
        }                                                                                           \
    }                                                                                               \
} while (0)

#define FILT3(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1,   \
              N0, N1, N2, N3, N4, N5, N6, N7, N8) do {                                              \
    if (PE != PH && PE != PF) {                                                                     \
        const unsigned e = df(PE,PC) + df(PE,PG) + df(PI,H5) + df(PI,F4) + (df(PH,PF)<<2);          \
        const unsigned i = df(PH,PD) + df(PH,I5) + df(PF,I4) + df(PF,PB) + (df(PE,PI)<<2);          \
        if (e < i && (!eq(PF,PB) && !eq(PF,PC) || !eq(PH,PD) && !eq(PH,PG) || eq(PE,PI)             \
                      && (!eq(PF,F4) && !eq(PF,I4) || !eq(PH,H5) && !eq(PH,I5))                     \
                      || eq(PE,PG) || eq(PE,PC))) {                                                 \
            const unsigned ke = df(PF,PG);                                                          \
            const unsigned ki = df(PH,PC);                                                          \
            const int left    = ke<<1 <= ki && PE != PG && PD != PG;                                \
            const int up      = ke >= ki<<1 && PE != PC && PB != PC;                                \
            const unsigned px = df(PE,PF) <= df(PE,PH) ? PF : PH;                                   \
            if (left && up) {                                                                       \
                ALPHA_BLEND_192_W(E[N7], px);                                                       \
                ALPHA_BLEND_64_W( E[N6], px);                                                       \
                E[N5] = E[N7];                                                                      \
                E[N2] = E[N6];                                                                      \
                E[N8] = px;                                                                         \
            } else if (left) {                                                                      \
                ALPHA_BLEND_192_W(E[N7], px);                                                       \
                ALPHA_BLEND_64_W( E[N5], px);                                                       \
                ALPHA_BLEND_64_W( E[N6], px);                                                       \
                E[N8] = px;                                                                         \
            } else if (up) {                                                                        \
                ALPHA_BLEND_192_W(E[N5], px);                                                       \
                ALPHA_BLEND_64_W( E[N7], px);                                                       \
                ALPHA_BLEND_64_W( E[N2], px);                                                       \
                E[N8] = px;                                                                         \
            } else { /* diagonal */                                                                 \
                ALPHA_BLEND_224_W(E[N8], px);                                                       \
                ALPHA_BLEND_32_W( E[N5], px);                                                       \
                ALPHA_BLEND_32_W( E[N7], px);                                                       \
            }                                                                                       \
        } else if (e <= i) {                                                                        \
            ALPHA_BLEND_128_W(E[N8], ((df(PE,PF) <= df(PE,PH)) ? PF : PH));                         \
        }                                                                                           \
    }                                                                                               \
} while (0)

#define FILT4(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1,   \
              N15, N14, N11, N3, N7, N10, N13, N12, N9, N6, N2, N1, N5, N8, N4, N0) do {            \
    if (PE != PH && PE != PF) {                                                                     \
        const unsigned e = df(PE,PC) + df(PE,PG) + df(PI,H5) + df(PI,F4) + (df(PH,PF)<<2);          \
        const unsigned i = df(PH,PD) + df(PH,I5) + df(PF,I4) + df(PF,PB) + (df(PE,PI)<<2);          \
        if (e < i && (!eq(PF,PB) && !eq(PH,PD) || eq(PE,PI)                                         \
                      && (!eq(PF,I4) && !eq(PH,I5))                                                 \
                      || eq(PE,PG) || eq(PE,PC))) {                                                 \
            const unsigned ke = df(PF,PG);                                                          \
            const unsigned ki = df(PH,PC);                                                          \
            const int left    = ke<<1 <= ki && PE != PG && PD != PG;                                \
            const int up      = ke >= ki<<1 && PE != PC && PB != PC;                                \
            const unsigned px = df(PE,PF) <= df(PE,PH) ? PF : PH;                                   \
            if (left && up) {                                                                       \
                ALPHA_BLEND_192_W(E[N13], px);                                                      \
                ALPHA_BLEND_64_W( E[N12], px);                                                      \
                E[N15] = E[N14] = E[N11] = px;                                                      \
                E[N10] = E[N3]  = E[N12];                                                           \
                E[N7]  = E[N13];                                                                    \
            } else if (left) {                                                                      \
                ALPHA_BLEND_192_W(E[N11], px);                                                      \
                ALPHA_BLEND_192_W(E[N13], px);                                                      \
                ALPHA_BLEND_64_W( E[N10], px);                                                      \
                ALPHA_BLEND_64_W( E[N12], px);                                                      \
                E[N14] = px;                                                                        \
                E[N15] = px;                                                                        \
            } else if (up) {                                                                        \
                ALPHA_BLEND_192_W(E[N14], px);                                                      \
                ALPHA_BLEND_192_W(E[N7 ], px);                                                      \
                ALPHA_BLEND_64_W( E[N10], px);                                                      \
                ALPHA_BLEND_64_W( E[N3 ], px);                                                      \
                E[N11] = px;                                                                        \
                E[N15] = px;                                                                        \
            } else { /* diagonal */                                                                 \
                ALPHA_BLEND_128_W(E[N11], px);                                                      \
                ALPHA_BLEND_128_W(E[N14], px);                                                      \
                E[N15] = px;                                                                        \
            }                                                                                       \
        } else if (e <= i) {                                                                        \
            ALPHA_BLEND_128_W( E[N15], ((df(PE,PF) <= df(PE,PH)) ? PF : PH));                       \
        }                                                                                           \
    }                                                                                               \
} while (0)

static av_always_inline void xbr_filter(const ThreadData *td, int jobnr, int nb_jobs, int n)
{
    int x, y;
    const AVFrame *input = td->in;
    AVFrame *output = td->out;
    const uint32_t *r2y = td->rgbtoyuv;
    const int slice_start = (input->height *  jobnr   ) / nb_jobs;
    const int slice_end   = (input->height * (jobnr+1)) / nb_jobs;
    const int nl = output->linesize[0] >> 2;
    const int nl1 = nl + nl;
    const int nl2 = nl1 + nl;

    for (y = slice_start; y < slice_end; y++) {

        uint32_t *E = (uint32_t *)(output->data[0] + y * output->linesize[0] * n);
        const uint32_t *sa2 = (uint32_t *)(input->data[0] + y * input->linesize[0] - 8); /* center */
        const uint32_t *sa1 = sa2 - (input->linesize[0]>>2); /* up x1 */
        const uint32_t *sa0 = sa1 - (input->linesize[0]>>2); /* up x2 */
        const uint32_t *sa3 = sa2 + (input->linesize[0]>>2); /* down x1 */
        const uint32_t *sa4 = sa3 + (input->linesize[0]>>2); /* down x2 */

        if (y <= 1) {
            sa0 = sa1;
            if (y == 0) {
                sa0 = sa1 = sa2;
            }
        }

        if (y >= input->height - 2) {
            sa4 = sa3;
            if (y == input->height - 1) {
                sa4 = sa3 = sa2;
            }
        }

        for (x = 0; x < input->width; x++) {
            const uint32_t B1 = sa0[2];
            const uint32_t PB = sa1[2];
            const uint32_t PE = sa2[2];
            const uint32_t PH = sa3[2];
            const uint32_t H5 = sa4[2];

            const int pprev = 2 - (x > 0);
            const uint32_t A1 = sa0[pprev];
            const uint32_t PA = sa1[pprev];
            const uint32_t PD = sa2[pprev];
            const uint32_t PG = sa3[pprev];
            const uint32_t G5 = sa4[pprev];

            const int pprev2 = pprev - (x > 1);
            const uint32_t A0 = sa1[pprev2];
            const uint32_t D0 = sa2[pprev2];
            const uint32_t G0 = sa3[pprev2];

            const int pnext = 3 - (x == input->width - 1);
            const uint32_t C1 = sa0[pnext];
            const uint32_t PC = sa1[pnext];
            const uint32_t PF = sa2[pnext];
            const uint32_t PI = sa3[pnext];
            const uint32_t I5 = sa4[pnext];

            const int pnext2 = pnext + 1 - (x >= input->width - 2);
            const uint32_t C4 = sa1[pnext2];
            const uint32_t F4 = sa2[pnext2];
            const uint32_t I4 = sa3[pnext2];

            if (n == 2) {
                E[0]  = E[1]      =     // 0, 1
                E[nl] = E[nl + 1] = PE; // 2, 3

                FILT2(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, 0, 1, nl, nl+1);
                FILT2(PE, PC, PF, PB, PI, PA, PH, PD, PG, I4, A1, I5, H5, A0, D0, B1, C1, F4, C4, G5, G0, nl, 0, nl+1, 1);
                FILT2(PE, PA, PB, PD, PC, PG, PF, PH, PI, C1, G0, C4, F4, G5, H5, D0, A0, B1, A1, I4, I5, nl+1, nl, 1, 0);
                FILT2(PE, PG, PD, PH, PA, PI, PB, PF, PC, A0, I5, A1, B1, I4, F4, H5, G5, D0, G0, C1, C4, 1, nl+1, 0, nl);
            } else if (n == 3) {
                E[0]   = E[1]     = E[2]     =     // 0, 1, 2
                E[nl]  = E[nl+1]  = E[nl+2]  =     // 3, 4, 5
                E[nl1] = E[nl1+1] = E[nl1+2] = PE; // 6, 7, 8

                FILT3(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, 0, 1, 2, nl, nl+1, nl+2, nl1, nl1+1, nl1+2);
                FILT3(PE, PC, PF, PB, PI, PA, PH, PD, PG, I4, A1, I5, H5, A0, D0, B1, C1, F4, C4, G5, G0, nl1, nl, 0, nl1+1, nl+1, 1, nl1+2, nl+2, 2);
                FILT3(PE, PA, PB, PD, PC, PG, PF, PH, PI, C1, G0, C4, F4, G5, H5, D0, A0, B1, A1, I4, I5, nl1+2, nl1+1, nl1, nl+2, nl+1, nl, 2, 1, 0);
                FILT3(PE, PG, PD, PH, PA, PI, PB, PF, PC, A0, I5, A1, B1, I4, F4, H5, G5, D0, G0, C1, C4, 2, nl+2, nl1+2, 1, nl+1, nl1+1, 0, nl, nl1);
            } else if (n == 4) {
                E[0]   = E[1]     = E[2]     = E[3]     =     //  0,  1,  2,  3
                E[nl]  = E[nl+1]  = E[nl+2]  = E[nl+3]  =     //  4,  5,  6,  7
                E[nl1] = E[nl1+1] = E[nl1+2] = E[nl1+3] =     //  8,  9, 10, 11
                E[nl2] = E[nl2+1] = E[nl2+2] = E[nl2+3] = PE; // 12, 13, 14, 15

                FILT4(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, nl2+3, nl2+2, nl1+3, 3, nl+3, nl1+2, nl2+1, nl2, nl1+1, nl+2, 2, 1, nl+1, nl1, nl, 0);
                FILT4(PE, PC, PF, PB, PI, PA, PH, PD, PG, I4, A1, I5, H5, A0, D0, B1, C1, F4, C4, G5, G0, 3, nl+3, 2, 0, 1, nl+2, nl1+3, nl2+3, nl1+2, nl+1, nl, nl1, nl1+1, nl2+2, nl2+1, nl2);
                FILT4(PE, PA, PB, PD, PC, PG, PF, PH, PI, C1, G0, C4, F4, G5, H5, D0, A0, B1, A1, I4, I5, 0, 1, nl, nl2, nl1, nl+1, 2, 3, nl+2, nl1+1, nl2+1, nl2+2, nl1+2, nl+3, nl1+3, nl2+3);
                FILT4(PE, PG, PD, PH, PA, PI, PB, PF, PC, A0, I5, A1, B1, I4, F4, H5, G5, D0, G0, C1, C4, nl2, nl1, nl2+1, nl2+3, nl2+2, nl1+1, nl, 0, nl+1, nl1+2, nl1+3, nl+3, nl+2, 1, 2, 3);
            }

            sa0 += 1;
            sa1 += 1;
            sa2 += 1;
            sa3 += 1;
            sa4 += 1;

            E += n;
        }
    }
}

#define XBR_FUNC(size) \
static int xbr##size##x(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs) \
{ \
    xbr_filter(arg, jobnr, nb_jobs, size); \
    return 0; \
}

XBR_FUNC(2)
XBR_FUNC(3)
XBR_FUNC(4)


static int config_output(AVFilterLink *outlink)
{
    AVFilterContext *ctx = outlink->src;
    XBRContext *xbr = ctx->priv;
    AVFilterLink *inlink = ctx->inputs[0];

    outlink->w = inlink->w * xbr->n;
    outlink->h = inlink->h * xbr->n;
    return 0;
}

static int query_formats(AVFilterContext *ctx)
{
    static const enum AVPixelFormat pix_fmts[] = {
        AV_PIX_FMT_0RGB32, AV_PIX_FMT_NONE,
    };

    ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
    return 0;
}

static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
    AVFilterContext *ctx = inlink->dst;
    AVFilterLink *outlink = ctx->outputs[0];
    XBRContext *xbr = ctx->priv;
    ThreadData td;

    AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
    if (!out) {
        av_frame_free(&in);
        return AVERROR(ENOMEM);
    }

    av_frame_copy_props(out, in);

    td.in = in;
    td.out = out;
    td.rgbtoyuv = xbr->rgbtoyuv;
    ctx->internal->execute(ctx, xbr->func, &td, NULL, FFMIN(inlink->h, ctx->graph->nb_threads));

    out->width  = outlink->w;
    out->height = outlink->h;

    av_frame_free(&in);
    return ff_filter_frame(outlink, out);
}

static int init(AVFilterContext *ctx)
{
    XBRContext *xbr = ctx->priv;
    static const xbrfunc_t xbrfuncs[] = {xbr2x, xbr3x, xbr4x};

    uint32_t c;
    int bg, rg, g;

    for (bg = -255; bg < 256; bg++) {
        for (rg = -255; rg < 256; rg++) {
            const uint32_t u = (uint32_t)((-169*rg + 500*bg)/1000) + 128;
            const uint32_t v = (uint32_t)(( 500*rg -  81*bg)/1000) + 128;
            int startg = FFMAX3(-bg, -rg, 0);
            int endg = FFMIN3(255-bg, 255-rg, 255);
            uint32_t y = (uint32_t)(( 299*rg + 1000*startg + 114*bg)/1000);
            c = bg + (rg<<16) + 0x010101 * startg;
            for (g = startg; g <= endg; g++) {
                xbr->rgbtoyuv[c] = ((y++) << 16) + (u << 8) + v;
                c+= 0x010101;
            }
        }
    }

    xbr->func = xbrfuncs[xbr->n - 2];
    return 0;
}

static const AVFilterPad xbr_inputs[] = {
    {
        .name         = "default",
        .type         = AVMEDIA_TYPE_VIDEO,
        .filter_frame = filter_frame,
    },
    { NULL }
};

static const AVFilterPad xbr_outputs[] = {
    {
        .name         = "default",
        .type         = AVMEDIA_TYPE_VIDEO,
        .config_props = config_output,
    },
    { NULL }
};

AVFilter ff_vf_xbr = {
    .name          = "xbr",
    .description   = NULL_IF_CONFIG_SMALL("Scale the input using xBR algorithm."),
    .inputs        = xbr_inputs,
    .outputs       = xbr_outputs,
    .query_formats = query_formats,
    .priv_size     = sizeof(XBRContext),
    .priv_class    = &xbr_class,
    .init          = init,
    .flags         = AVFILTER_FLAG_SLICE_THREADS,
};
Commit	Line	Data
f6fa7814 DM	1	/*
	2	* This file is part of FFmpeg.
	3	*
	4	* Copyright (c) 2011, 2012 Hyllian/Jararaca <sergiogdb@gmail.com>
	5	* Copyright (c) 2014 Arwa Arif <arwaarif1994@gmail.com>
	6	*
	7	* FFmpeg is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU Lesser General Public
	9	* License as published by the Free Software Foundation; either
	10	* version 2.1 of the License, or (at your option) any later version.
	11	*
	12	* FFmpeg is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	* Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public
	18	* License along with FFmpeg; if not, write to the Free Software
	19	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	20	*/
	21
	22	/**
	23	* @file
	24	* XBR Filter is used for depixelization of image.
	25	* This is based on Hyllian's xBR shader.
	26	*
	27	* @see http://www.libretro.com/forums/viewtopic.php?f=6&t=134
	28	* @see https://github.com/yoyofr/iFBA/blob/master/fba_src/src/intf/video/scalers/xbr.cpp
	29	*/
	30
	31	#include "libavutil/opt.h"
	32	#include "libavutil/avassert.h"
	33	#include "libavutil/pixdesc.h"
	34	#include "internal.h"
	35
	36	#define RGB_MASK 0x00FFFFFF
	37	#define LB_MASK 0x00FEFEFE
	38	#define RED_BLUE_MASK 0x00FF00FF
	39	#define GREEN_MASK 0x0000FF00
	40
	41	typedef int (xbrfunc_t)(AVFilterContext ctx, void *arg, int jobnr, int nb_jobs);
	42
	43	typedef struct {
	44	const AVClass *class;
	45	int n;
	46	xbrfunc_t func;
	47	uint32_t rgbtoyuv[1<<24];
	48	} XBRContext;
	49
	50	typedef struct ThreadData {
	51	AVFrame in, out;
	52	const uint32_t *rgbtoyuv;
	53	} ThreadData;
	54
	55	#define OFFSET(x) offsetof(XBRContext, x)
	56	#define FLAGS AV_OPT_FLAG_FILTERING_PARAM\|AV_OPT_FLAG_VIDEO_PARAM
	57	static const AVOption xbr_options[] = {
	58	{ "n", "set scale factor", OFFSET(n), AV_OPT_TYPE_INT, {.i64 = 3}, 2, 4, .flags = FLAGS },
	59	{ NULL }
	60	};
	61
	62	AVFILTER_DEFINE_CLASS(xbr);
	63
	64	static uint32_t pixel_diff(uint32_t x, uint32_t y, const uint32_t *r2y)
65	{
66	#define YMASK 0xff0000
67	#define UMASK 0x00ff00
68	#define VMASK 0x0000ff
69
70	uint32_t yuv1 = r2y[x & 0xffffff];
71	uint32_t yuv2 = r2y[y & 0xffffff];
72
73	return (abs((yuv1 & YMASK) - (yuv2 & YMASK)) >> 16) +
74	(abs((yuv1 & UMASK) - (yuv2 & UMASK)) >> 8) +
75	abs((yuv1 & VMASK) - (yuv2 & VMASK));
76	}
77
78	#define ALPHA_BLEND_128_W(dst, src) dst = ((src & LB_MASK) >> 1) + ((dst & LB_MASK) >> 1)
79
80	#define ALPHA_BLEND_32_W(dst, src) \
81	dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
82	(dst & RED_BLUE_MASK))) >> 3))) \| (GREEN_MASK & ((dst & GREEN_MASK) + \
83	((((src & GREEN_MASK) - (dst & GREEN_MASK))) >> 3))))
84
85	#define ALPHA_BLEND_64_W(dst, src) \
86	dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
87	(dst & RED_BLUE_MASK))) >> 2))) \| (GREEN_MASK & ((dst & GREEN_MASK) + \
88	((((src & GREEN_MASK) - (dst & GREEN_MASK))) >> 2))))
89
90	#define ALPHA_BLEND_192_W(dst, src) \
91	dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
92	(dst & RED_BLUE_MASK)) * 3) >> 2))) \| (GREEN_MASK & ((dst & GREEN_MASK) + \
93	((((src & GREEN_MASK) - (dst & GREEN_MASK)) * 3) >> 2))))
94
95	#define ALPHA_BLEND_224_W(dst, src) \
96	dst = ((RED_BLUE_MASK & ((dst & RED_BLUE_MASK) + ((((src & RED_BLUE_MASK) - \
97	(dst & RED_BLUE_MASK)) * 7) >> 3))) \| (GREEN_MASK & ((dst & GREEN_MASK) + \
98	((((src & GREEN_MASK) - (dst & GREEN_MASK)) * 7) >> 3))))
99
100	#define df(A, B) pixel_diff(A, B, r2y)
101	#define eq(A, B) (df(A, B) < 155)
102
103	#define FILT2(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, \
104	N0, N1, N2, N3) do { \
105	if (PE != PH && PE != PF) { \
106	const unsigned e = df(PE,PC) + df(PE,PG) + df(PI,H5) + df(PI,F4) + (df(PH,PF)<<2); \
107	const unsigned i = df(PH,PD) + df(PH,I5) + df(PF,I4) + df(PF,PB) + (df(PE,PI)<<2); \
108	if (e < i && (!eq(PF,PB) && !eq(PH,PD) \|\| eq(PE,PI) \
109	&& (!eq(PF,I4) && !eq(PH,I5)) \
110	\|\| eq(PE,PG) \|\| eq(PE,PC))) { \
111	const unsigned ke = df(PF,PG); \
112	const unsigned ki = df(PH,PC); \
113	const int left = ke<<1 <= ki && PE != PG && PD != PG; \
114	const int up = ke >= ki<<1 && PE != PC && PB != PC; \
115	const unsigned px = df(PE,PF) <= df(PE,PH) ? PF : PH; \
116	if (left && up) { \
117	ALPHA_BLEND_224_W(E[N3], px); \
118	ALPHA_BLEND_64_W( E[N2], px); \
119	E[N1] = E[N2]; \
120	} else if (left) { \
121	ALPHA_BLEND_192_W(E[N3], px); \
122	ALPHA_BLEND_64_W( E[N2], px); \
123	} else if (up) { \
124	ALPHA_BLEND_192_W(E[N3], px); \
125	ALPHA_BLEND_64_W( E[N1], px); \
126	} else { /* diagonal */ \
127	ALPHA_BLEND_128_W(E[N3], px); \
128	} \
129	} else if (e <= i) { \
130	ALPHA_BLEND_128_W( E[N3], ((df(PE,PF) <= df(PE,PH)) ? PF : PH)); \
131	} \
132	} \
133	} while (0)
134
135	#define FILT3(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, \
136	N0, N1, N2, N3, N4, N5, N6, N7, N8) do { \
137	if (PE != PH && PE != PF) { \
138	const unsigned e = df(PE,PC) + df(PE,PG) + df(PI,H5) + df(PI,F4) + (df(PH,PF)<<2); \
139	const unsigned i = df(PH,PD) + df(PH,I5) + df(PF,I4) + df(PF,PB) + (df(PE,PI)<<2); \
140	if (e < i && (!eq(PF,PB) && !eq(PF,PC) \|\| !eq(PH,PD) && !eq(PH,PG) \|\| eq(PE,PI) \
141	&& (!eq(PF,F4) && !eq(PF,I4) \|\| !eq(PH,H5) && !eq(PH,I5)) \
142	\|\| eq(PE,PG) \|\| eq(PE,PC))) { \
143	const unsigned ke = df(PF,PG); \
144	const unsigned ki = df(PH,PC); \
145	const int left = ke<<1 <= ki && PE != PG && PD != PG; \
146	const int up = ke >= ki<<1 && PE != PC && PB != PC; \
147	const unsigned px = df(PE,PF) <= df(PE,PH) ? PF : PH; \
148	if (left && up) { \
149	ALPHA_BLEND_192_W(E[N7], px); \
150	ALPHA_BLEND_64_W( E[N6], px); \
151	E[N5] = E[N7]; \
152	E[N2] = E[N6]; \
153	E[N8] = px; \
154	} else if (left) { \
155	ALPHA_BLEND_192_W(E[N7], px); \
156	ALPHA_BLEND_64_W( E[N5], px); \
157	ALPHA_BLEND_64_W( E[N6], px); \
158	E[N8] = px; \
159	} else if (up) { \
160	ALPHA_BLEND_192_W(E[N5], px); \
161	ALPHA_BLEND_64_W( E[N7], px); \
162	ALPHA_BLEND_64_W( E[N2], px); \
163	E[N8] = px; \
164	} else { /* diagonal */ \
165	ALPHA_BLEND_224_W(E[N8], px); \
166	ALPHA_BLEND_32_W( E[N5], px); \
167	ALPHA_BLEND_32_W( E[N7], px); \
168	} \
169	} else if (e <= i) { \
170	ALPHA_BLEND_128_W(E[N8], ((df(PE,PF) <= df(PE,PH)) ? PF : PH)); \
171	} \
172	} \
173	} while (0)
174
175	#define FILT4(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, \
176	N15, N14, N11, N3, N7, N10, N13, N12, N9, N6, N2, N1, N5, N8, N4, N0) do { \
177	if (PE != PH && PE != PF) { \
178	const unsigned e = df(PE,PC) + df(PE,PG) + df(PI,H5) + df(PI,F4) + (df(PH,PF)<<2); \
179	const unsigned i = df(PH,PD) + df(PH,I5) + df(PF,I4) + df(PF,PB) + (df(PE,PI)<<2); \
180	if (e < i && (!eq(PF,PB) && !eq(PH,PD) \|\| eq(PE,PI) \
181	&& (!eq(PF,I4) && !eq(PH,I5)) \
182	\|\| eq(PE,PG) \|\| eq(PE,PC))) { \
183	const unsigned ke = df(PF,PG); \
184	const unsigned ki = df(PH,PC); \
185	const int left = ke<<1 <= ki && PE != PG && PD != PG; \
186	const int up = ke >= ki<<1 && PE != PC && PB != PC; \
187	const unsigned px = df(PE,PF) <= df(PE,PH) ? PF : PH; \
188	if (left && up) { \
189	ALPHA_BLEND_192_W(E[N13], px); \
190	ALPHA_BLEND_64_W( E[N12], px); \
191	E[N15] = E[N14] = E[N11] = px; \
192	E[N10] = E[N3] = E[N12]; \
193	E[N7] = E[N13]; \
194	} else if (left) { \
195	ALPHA_BLEND_192_W(E[N11], px); \
196	ALPHA_BLEND_192_W(E[N13], px); \
197	ALPHA_BLEND_64_W( E[N10], px); \
198	ALPHA_BLEND_64_W( E[N12], px); \
199	E[N14] = px; \
200	E[N15] = px; \
201	} else if (up) { \
202	ALPHA_BLEND_192_W(E[N14], px); \
203	ALPHA_BLEND_192_W(E[N7 ], px); \
204	ALPHA_BLEND_64_W( E[N10], px); \
205	ALPHA_BLEND_64_W( E[N3 ], px); \
206	E[N11] = px; \
207	E[N15] = px; \
208	} else { /* diagonal */ \
209	ALPHA_BLEND_128_W(E[N11], px); \
210	ALPHA_BLEND_128_W(E[N14], px); \
211	E[N15] = px; \
212	} \
213	} else if (e <= i) { \
214	ALPHA_BLEND_128_W( E[N15], ((df(PE,PF) <= df(PE,PH)) ? PF : PH)); \
215	} \
216	} \
217	} while (0)
218
219	static av_always_inline void xbr_filter(const ThreadData *td, int jobnr, int nb_jobs, int n)
220	{
221	int x, y;
222	const AVFrame *input = td->in;
223	AVFrame *output = td->out;
224	const uint32_t *r2y = td->rgbtoyuv;
225	const int slice_start = (input->height * jobnr ) / nb_jobs;
226	const int slice_end = (input->height * (jobnr+1)) / nb_jobs;
227	const int nl = output->linesize[0] >> 2;
228	const int nl1 = nl + nl;
229	const int nl2 = nl1 + nl;
230
231	for (y = slice_start; y < slice_end; y++) {
232
233	uint32_t E = (uint32_t )(output->data[0] + y * output->linesize[0] * n);
234	const uint32_t sa2 = (uint32_t )(input->data[0] + y * input->linesize[0] - 8); /* center */
235	const uint32_t sa1 = sa2 - (input->linesize[0]>>2); / up x1 */
236	const uint32_t sa0 = sa1 - (input->linesize[0]>>2); / up x2 */
237	const uint32_t sa3 = sa2 + (input->linesize[0]>>2); / down x1 */
238	const uint32_t sa4 = sa3 + (input->linesize[0]>>2); / down x2 */
239
240	if (y <= 1) {
241	sa0 = sa1;
242	if (y == 0) {
243	sa0 = sa1 = sa2;
244	}
245	}
246
247	if (y >= input->height - 2) {
248	sa4 = sa3;
249	if (y == input->height - 1) {
250	sa4 = sa3 = sa2;
251	}
252	}
253
254	for (x = 0; x < input->width; x++) {
255	const uint32_t B1 = sa0[2];
256	const uint32_t PB = sa1[2];
257	const uint32_t PE = sa2[2];
258	const uint32_t PH = sa3[2];
259	const uint32_t H5 = sa4[2];
260
261	const int pprev = 2 - (x > 0);
262	const uint32_t A1 = sa0[pprev];
263	const uint32_t PA = sa1[pprev];
264	const uint32_t PD = sa2[pprev];
265	const uint32_t PG = sa3[pprev];
266	const uint32_t G5 = sa4[pprev];
267
268	const int pprev2 = pprev - (x > 1);
269	const uint32_t A0 = sa1[pprev2];
270	const uint32_t D0 = sa2[pprev2];
271	const uint32_t G0 = sa3[pprev2];
272
273	const int pnext = 3 - (x == input->width - 1);
274	const uint32_t C1 = sa0[pnext];
275	const uint32_t PC = sa1[pnext];
276	const uint32_t PF = sa2[pnext];
277	const uint32_t PI = sa3[pnext];
278	const uint32_t I5 = sa4[pnext];
279
280	const int pnext2 = pnext + 1 - (x >= input->width - 2);
281	const uint32_t C4 = sa1[pnext2];
282	const uint32_t F4 = sa2[pnext2];
283	const uint32_t I4 = sa3[pnext2];
284
285	if (n == 2) {
286	E[0] = E[1] = // 0, 1
287	E[nl] = E[nl + 1] = PE; // 2, 3
288
289	FILT2(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, 0, 1, nl, nl+1);
290	FILT2(PE, PC, PF, PB, PI, PA, PH, PD, PG, I4, A1, I5, H5, A0, D0, B1, C1, F4, C4, G5, G0, nl, 0, nl+1, 1);
291	FILT2(PE, PA, PB, PD, PC, PG, PF, PH, PI, C1, G0, C4, F4, G5, H5, D0, A0, B1, A1, I4, I5, nl+1, nl, 1, 0);
292	FILT2(PE, PG, PD, PH, PA, PI, PB, PF, PC, A0, I5, A1, B1, I4, F4, H5, G5, D0, G0, C1, C4, 1, nl+1, 0, nl);
293	} else if (n == 3) {
294	E[0] = E[1] = E[2] = // 0, 1, 2
295	E[nl] = E[nl+1] = E[nl+2] = // 3, 4, 5
296	E[nl1] = E[nl1+1] = E[nl1+2] = PE; // 6, 7, 8
297
298	FILT3(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, 0, 1, 2, nl, nl+1, nl+2, nl1, nl1+1, nl1+2);
299	FILT3(PE, PC, PF, PB, PI, PA, PH, PD, PG, I4, A1, I5, H5, A0, D0, B1, C1, F4, C4, G5, G0, nl1, nl, 0, nl1+1, nl+1, 1, nl1+2, nl+2, 2);
300	FILT3(PE, PA, PB, PD, PC, PG, PF, PH, PI, C1, G0, C4, F4, G5, H5, D0, A0, B1, A1, I4, I5, nl1+2, nl1+1, nl1, nl+2, nl+1, nl, 2, 1, 0);
301	FILT3(PE, PG, PD, PH, PA, PI, PB, PF, PC, A0, I5, A1, B1, I4, F4, H5, G5, D0, G0, C1, C4, 2, nl+2, nl1+2, 1, nl+1, nl1+1, 0, nl, nl1);
302	} else if (n == 4) {
303	E[0] = E[1] = E[2] = E[3] = // 0, 1, 2, 3
304	E[nl] = E[nl+1] = E[nl+2] = E[nl+3] = // 4, 5, 6, 7
305	E[nl1] = E[nl1+1] = E[nl1+2] = E[nl1+3] = // 8, 9, 10, 11
306	E[nl2] = E[nl2+1] = E[nl2+2] = E[nl2+3] = PE; // 12, 13, 14, 15
307
308	FILT4(PE, PI, PH, PF, PG, PC, PD, PB, PA, G5, C4, G0, D0, C1, B1, F4, I4, H5, I5, A0, A1, nl2+3, nl2+2, nl1+3, 3, nl+3, nl1+2, nl2+1, nl2, nl1+1, nl+2, 2, 1, nl+1, nl1, nl, 0);
309	FILT4(PE, PC, PF, PB, PI, PA, PH, PD, PG, I4, A1, I5, H5, A0, D0, B1, C1, F4, C4, G5, G0, 3, nl+3, 2, 0, 1, nl+2, nl1+3, nl2+3, nl1+2, nl+1, nl, nl1, nl1+1, nl2+2, nl2+1, nl2);
310	FILT4(PE, PA, PB, PD, PC, PG, PF, PH, PI, C1, G0, C4, F4, G5, H5, D0, A0, B1, A1, I4, I5, 0, 1, nl, nl2, nl1, nl+1, 2, 3, nl+2, nl1+1, nl2+1, nl2+2, nl1+2, nl+3, nl1+3, nl2+3);
311	FILT4(PE, PG, PD, PH, PA, PI, PB, PF, PC, A0, I5, A1, B1, I4, F4, H5, G5, D0, G0, C1, C4, nl2, nl1, nl2+1, nl2+3, nl2+2, nl1+1, nl, 0, nl+1, nl1+2, nl1+3, nl+3, nl+2, 1, 2, 3);
312	}
313
314	sa0 += 1;
315	sa1 += 1;
316	sa2 += 1;
317	sa3 += 1;
318	sa4 += 1;
319
320	E += n;
321	}
322	}
323	}
324
325	#define XBR_FUNC(size) \
326	static int xbr##size##x(AVFilterContext ctx, void arg, int jobnr, int nb_jobs) \
327	{ \
328	xbr_filter(arg, jobnr, nb_jobs, size); \
329	return 0; \
330	}
331
332	XBR_FUNC(2)
333	XBR_FUNC(3)
334	XBR_FUNC(4)
335
336
337	static int config_output(AVFilterLink *outlink)
338	{
339	AVFilterContext *ctx = outlink->src;
340	XBRContext *xbr = ctx->priv;
341	AVFilterLink *inlink = ctx->inputs[0];
342
343	outlink->w = inlink->w * xbr->n;
344	outlink->h = inlink->h * xbr->n;
345	return 0;
346	}
347
348	static int query_formats(AVFilterContext *ctx)
349	{
350	static const enum AVPixelFormat pix_fmts[] = {
351	AV_PIX_FMT_0RGB32, AV_PIX_FMT_NONE,
352	};
353
354	ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
355	return 0;
356	}
357
358	static int filter_frame(AVFilterLink inlink, AVFrame in)
359	{
360	AVFilterContext *ctx = inlink->dst;
361	AVFilterLink *outlink = ctx->outputs[0];
362	XBRContext *xbr = ctx->priv;
363	ThreadData td;
364
365	AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
366	if (!out) {
367	av_frame_free(&in);
368	return AVERROR(ENOMEM);
369	}
370
371	av_frame_copy_props(out, in);
372
373	td.in = in;
374	td.out = out;
375	td.rgbtoyuv = xbr->rgbtoyuv;
376	ctx->internal->execute(ctx, xbr->func, &td, NULL, FFMIN(inlink->h, ctx->graph->nb_threads));
377
378	out->width = outlink->w;
379	out->height = outlink->h;
380
381	av_frame_free(&in);
382	return ff_filter_frame(outlink, out);
383	}
384
385	static int init(AVFilterContext *ctx)
386	{
387	XBRContext *xbr = ctx->priv;
388	static const xbrfunc_t xbrfuncs[] = {xbr2x, xbr3x, xbr4x};
389
390	uint32_t c;
391	int bg, rg, g;
392
393	for (bg = -255; bg < 256; bg++) {
394	for (rg = -255; rg < 256; rg++) {
395	const uint32_t u = (uint32_t)((-169rg + 500bg)/1000) + 128;
396	const uint32_t v = (uint32_t)(( 500rg - 81bg)/1000) + 128;
397	int startg = FFMAX3(-bg, -rg, 0);
398	int endg = FFMIN3(255-bg, 255-rg, 255);
399	uint32_t y = (uint32_t)(( 299rg + 1000startg + 114*bg)/1000);
400	c = bg + (rg<<16) + 0x010101 * startg;
401	for (g = startg; g <= endg; g++) {
402	xbr->rgbtoyuv[c] = ((y++) << 16) + (u << 8) + v;
403	c+= 0x010101;
404	}
405	}
406	}
407
408	xbr->func = xbrfuncs[xbr->n - 2];
409	return 0;
410	}
411
412	static const AVFilterPad xbr_inputs[] = {
413	{
414	.name = "default",
415	.type = AVMEDIA_TYPE_VIDEO,
416	.filter_frame = filter_frame,
417	},
418	{ NULL }
419	};
420
421	static const AVFilterPad xbr_outputs[] = {
422	{
423	.name = "default",
424	.type = AVMEDIA_TYPE_VIDEO,
425	.config_props = config_output,
426	},
427	{ NULL }
428	};
429
430	AVFilter ff_vf_xbr = {
431	.name = "xbr",
432	.description = NULL_IF_CONFIG_SMALL("Scale the input using xBR algorithm."),
433	.inputs = xbr_inputs,
434	.outputs = xbr_outputs,
435	.query_formats = query_formats,
436	.priv_size = sizeof(XBRContext),
437	.priv_class = &xbr_class,
438	.init = init,
439	.flags = AVFILTER_FLAG_SLICE_THREADS,
440	};