1/*
2 * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21/**
22 * @file
23 * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder DSP routines
24 */
25
26#include "mss2dsp.h"
27#include "libavutil/common.h"
28
29static av_always_inline void mss2_blit_wmv9_template(uint8_t *dst,
30                                                     int dst_stride,
31                                                     int gray,
32                                                     int use_mask,
33                                                     int maskcolor,
34                                                     const uint8_t *mask,
35                                                     int mask_stride,
36                                                     const uint8_t *srcy,
37                                                     int srcy_stride,
38                                                     const uint8_t *srcu,
39                                                     const uint8_t *srcv,
40                                                     int srcuv_stride,
41                                                     int w, int h)
42{
43    int i, j, k, r = -1;
44    while (++r < h) {
45        for (i = 0, j = 0, k = 0; i < w; j += (i & 1), i++, k += 3) {
46            if (!use_mask || mask[i] == maskcolor) {
47                if (gray) {
48                    dst[k] = dst[k + 1] = dst[k + 2] = 0x80;
49                } else {
50                    int y = srcy[i];
51                    int u = srcu[j] - 128;
52                    int v = srcv[j] - 128;
53                    dst[k]     = av_clip_uint8(y + (             91881 * v + 32768 >> 16));
54                    dst[k + 1] = av_clip_uint8(y + (-22554 * u - 46802 * v + 32768 >> 16));
55                    dst[k + 2] = av_clip_uint8(y + (116130 * u             + 32768 >> 16));
56                }
57            }
58        }
59        mask +=  mask_stride;
60        dst  +=   dst_stride;
61        srcy +=  srcy_stride;
62        srcu += srcuv_stride * (r & 1);
63        srcv += srcuv_stride * (r & 1);
64    }
65}
66
67static void mss2_blit_wmv9_c(uint8_t *dst, int dst_stride,
68                             const uint8_t *srcy, int srcy_stride,
69                             const uint8_t *srcu, const uint8_t *srcv,
70                             int srcuv_stride, int w, int h)
71{
72    mss2_blit_wmv9_template(dst, dst_stride, 0, 0,
73                            0, NULL, 0,
74                            srcy, srcy_stride,
75                            srcu, srcv, srcuv_stride,
76                            w, h);
77}
78
79static void mss2_blit_wmv9_masked_c(uint8_t *dst, int dst_stride,
80                                    int maskcolor, const uint8_t *mask,
81                                    int mask_stride,
82                                    const uint8_t *srcy, int srcy_stride,
83                                    const uint8_t *srcu, const uint8_t *srcv,
84                                    int srcuv_stride, int w, int h)
85{
86    mss2_blit_wmv9_template(dst, dst_stride, 0, 1,
87                            maskcolor, mask, mask_stride,
88                            srcy, srcy_stride,
89                            srcu, srcv, srcuv_stride,
90                            w, h);
91}
92
93static void mss2_gray_fill_masked_c(uint8_t *dst, int dst_stride,
94                                    int maskcolor, const uint8_t *mask,
95                                    int mask_stride, int w, int h)
96{
97    mss2_blit_wmv9_template(dst, dst_stride, 1, 1,
98                            maskcolor, mask, mask_stride,
99                            NULL, 0,
100                            NULL, NULL, 0,
101                            w, h);
102}
103
104static void upsample_plane_c(uint8_t *plane, int plane_stride, int w, int h)
105{
106    uint8_t *src1, *src2, *dst1, *dst2, *p, a, b;
107    int i, j;
108
109    if(!w || !h)
110        return;
111
112    w += (w & 1);
113    h += (h & 1);
114
115    j = h - 1;
116
117    memcpy(plane + plane_stride *  j,
118           plane + plane_stride * (j >> 1),
119           w);
120
121    while ((j -= 2) > 0) {
122        dst1 = plane + plane_stride *  (j + 1);
123        dst2 = plane + plane_stride *   j;
124        src1 = plane + plane_stride * ((j + 1) >> 1);
125        src2 = plane + plane_stride * ( j      >> 1);
126
127        for (i = (w - 1) >> 1; i >= 0; i--) {
128            a = src1[i];
129            b = src2[i];
130            dst1[i] = (3 * a + b + 2) >> 2;
131            dst2[i] = (a + 3 * b + 2) >> 2;
132        }
133    }
134
135    for (j = h - 1; j >= 0; j--) {
136        p = plane + plane_stride * j;
137        i = w - 1;
138
139        p[i] = p[i >> 1];
140
141        while ((i -= 2) > 0) {
142            a = p[ i      >> 1];
143            b = p[(i + 1) >> 1];
144            p[i]     = (3 * a + b + 1) >> 2;
145            p[i + 1] = (a + 3 * b + 1) >> 2;
146        }
147    }
148}
149
150av_cold void ff_mss2dsp_init(MSS2DSPContext* dsp)
151{
152    dsp->mss2_blit_wmv9        = mss2_blit_wmv9_c;
153    dsp->mss2_blit_wmv9_masked = mss2_blit_wmv9_masked_c;
154    dsp->mss2_gray_fill_masked = mss2_gray_fill_masked_c;
155    dsp->upsample_plane        = upsample_plane_c;
156}
157