/*

 * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

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

 */

/**

 * @file

 * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder DSP routines

 */

#include "mss2dsp.h"

#include "libavutil/common.h"

static av_always_inline void mss2_blit_wmv9_template(uint8_t *dst,

                                                     ptrdiff_t dst_stride,

                                                     int gray,

                                                     int use_mask,

                                                     int maskcolor,

                                                     const uint8_t *mask,

                                                     ptrdiff_t mask_stride,

                                                     const uint8_t *srcy,

                                                     ptrdiff_t srcy_stride,

                                                     const uint8_t *srcu,

                                                     const uint8_t *srcv,

                                                     ptrdiff_t srcuv_stride,

                                                     int w, int h)

{

    int i, j, k, r = -1;

    while (++r < h) {

        for (i = 0, j = 0, k = 0; i < w; j += (i & 1), i++, k += 3) {

            if (!use_mask || mask[i] == maskcolor) {

                if (gray) {

                    dst[k] = dst[k + 1] = dst[k + 2] = 0x80;

                } else {

                    int y = srcy[i];

                    int u = srcu[j] - 128;

                    int v = srcv[j] - 128;

                    dst[k]     = av_clip_uint8(y + (             91881 * v + 32768 >> 16));

                    dst[k + 1] = av_clip_uint8(y + (-22554 * u - 46802 * v + 32768 >> 16));

                    dst[k + 2] = av_clip_uint8(y + (116130 * u             + 32768 >> 16));

                }

            }

        }

        mask  = FF_PTR_ADD(mask, mask_stride);

        dst  +=   dst_stride;

        srcy +=  srcy_stride;

        srcu += srcuv_stride * (r & 1);

        srcv += srcuv_stride * (r & 1);

    }

}

static void mss2_blit_wmv9_c(uint8_t *dst, ptrdiff_t dst_stride,

                             const uint8_t *srcy, ptrdiff_t srcy_stride,

                             const uint8_t *srcu, const uint8_t *srcv,

                             ptrdiff_t srcuv_stride, int w, int h)

{

    mss2_blit_wmv9_template(dst, dst_stride, 0, 0,

                            0, NULL, 0,

                            srcy, srcy_stride,

                            srcu, srcv, srcuv_stride,

                            w, h);

}

static void mss2_blit_wmv9_masked_c(uint8_t *dst, ptrdiff_t dst_stride,

                                    int maskcolor, const uint8_t *mask,

                                    ptrdiff_t mask_stride,

                                    const uint8_t *srcy, ptrdiff_t srcy_stride,

                                    const uint8_t *srcu, const uint8_t *srcv,

                                    ptrdiff_t srcuv_stride, int w, int h)

{

    mss2_blit_wmv9_template(dst, dst_stride, 0, 1,

                            maskcolor, mask, mask_stride,

                            srcy, srcy_stride,

                            srcu, srcv, srcuv_stride,

                            w, h);

}

static void mss2_gray_fill_masked_c(uint8_t *dst, ptrdiff_t dst_stride,

                                    int maskcolor, const uint8_t *mask,

                                    ptrdiff_t mask_stride, int w, int h)

{

    mss2_blit_wmv9_template(dst, dst_stride, 1, 1,

                            maskcolor, mask, mask_stride,

                            NULL, 0,

                            NULL, NULL, 0,

                            w, h);

}

static void upsample_plane_c(uint8_t *plane, ptrdiff_t plane_stride, int w, int h)

{

    uint8_t *src1, *src2, *dst1, *dst2, *p, a, b;

    int i, j;

    if(!w || !h)

        return;

    w += (w & 1);

    h += (h & 1);

    j = h - 1;

    memcpy(plane + plane_stride *  j,

           plane + plane_stride * (j >> 1),

           w);

    while ((j -= 2) > 0) {

        dst1 = plane + plane_stride *  (j + 1);

        dst2 = plane + plane_stride *   j;

        src1 = plane + plane_stride * ((j + 1) >> 1);

        src2 = plane + plane_stride * ( j      >> 1);

        for (i = (w - 1) >> 1; i >= 0; i--) {

            a = src1[i];

            b = src2[i];

            dst1[i] = (3 * a + b + 2) >> 2;

            dst2[i] = (a + 3 * b + 2) >> 2;

        }

    }

    for (j = h - 1; j >= 0; j--) {

        p = plane + plane_stride * j;

        i = w - 1;

        p[i] = p[i >> 1];

        while ((i -= 2) > 0) {

            a = p[ i      >> 1];

            b = p[(i + 1) >> 1];

            p[i]     = (3 * a + b + 1) >> 2;

            p[i + 1] = (a + 3 * b + 1) >> 2;

        }

    }

}

av_cold void ff_mss2dsp_init(MSS2DSPContext* dsp)

{

    dsp->mss2_blit_wmv9        = mss2_blit_wmv9_c;

    dsp->mss2_blit_wmv9_masked = mss2_blit_wmv9_masked_c;

    dsp->mss2_gray_fill_masked = mss2_gray_fill_masked_c;

    dsp->upsample_plane        = upsample_plane_c;

}