1/*
2 * Copyright (c) 2015-2016 Kieran Kunhya <kieran@kunhya.com>
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#include "libavutil/attributes.h"
22#include "libavutil/common.h"
23
24#include "cfhdencdsp.h"
25
26static av_always_inline void filter(int16_t *input, ptrdiff_t in_stride,
27                          int16_t *low, ptrdiff_t low_stride,
28                          int16_t *high, ptrdiff_t high_stride,
29                          int len)
30{
31    low[(0>>1) * low_stride]   = av_clip_int16(input[0*in_stride] + input[1*in_stride]);
32    high[(0>>1) * high_stride] = av_clip_int16((5 * input[0*in_stride] - 11 * input[1*in_stride] +
33                                                4 * input[2*in_stride] +  4 * input[3*in_stride] -
34                                                1 * input[4*in_stride] -  1 * input[5*in_stride] + 4) >> 3);
35
36    for (int i = 2; i < len - 2; i += 2) {
37        low[(i>>1) * low_stride]   = av_clip_int16(input[i*in_stride] + input[(i+1)*in_stride]);
38        high[(i>>1) * high_stride] = av_clip_int16(((-input[(i-2)*in_stride] - input[(i-1)*in_stride] +
39                                                      input[(i+2)*in_stride] + input[(i+3)*in_stride] + 4) >> 3) +
40                                                      input[(i+0)*in_stride] - input[(i+1)*in_stride]);
41    }
42
43    low[((len-2)>>1) * low_stride]   = av_clip_int16(input[((len-2)+0)*in_stride] + input[((len-2)+1)*in_stride]);
44    high[((len-2)>>1) * high_stride] = av_clip_int16((11* input[((len-2)+0)*in_stride] - 5 * input[((len-2)+1)*in_stride] -
45                                                      4 * input[((len-2)-1)*in_stride] - 4 * input[((len-2)-2)*in_stride] +
46                                                      1 * input[((len-2)-3)*in_stride] + 1 * input[((len-2)-4)*in_stride] + 4) >> 3);
47}
48
49static void horiz_filter(int16_t *input, int16_t *low, int16_t *high,
50                         ptrdiff_t in_stride, ptrdiff_t low_stride,
51                         ptrdiff_t high_stride,
52                         int width, int height)
53{
54    for (int i = 0; i < height; i++) {
55        filter(input, 1, low, 1, high, 1, width);
56        input += in_stride;
57        low += low_stride;
58        high += high_stride;
59    }
60}
61
62static void vert_filter(int16_t *input, int16_t *low, int16_t *high,
63                        ptrdiff_t in_stride, ptrdiff_t low_stride,
64                        ptrdiff_t high_stride,
65                        int width, int height)
66{
67    for (int i = 0; i < width; i++)
68        filter(&input[i], in_stride, &low[i], low_stride, &high[i], high_stride, height);
69}
70
71av_cold void ff_cfhdencdsp_init(CFHDEncDSPContext *c)
72{
73    c->horiz_filter = horiz_filter;
74    c->vert_filter = vert_filter;
75
76#if ARCH_X86
77    ff_cfhdencdsp_init_x86(c);
78#endif
79}
80