xref: /third_party/ffmpeg/libavcodec/hpeldsp.h (revision cabdff1a)
1/*
2 * Half-pel DSP functions.
3 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23/**
24 * @file
25 * Half-pel DSP functions.
26 */
27
28#ifndef AVCODEC_HPELDSP_H
29#define AVCODEC_HPELDSP_H
30
31#include <stdint.h>
32#include <stddef.h>
33
34/* add and put pixel (decoding) */
35// blocksizes for hpel_pixels_func are 8x4,8x8 16x8 16x16
36// h for hpel_pixels_func is limited to {width/2, width} but never larger
37// than 16 and never smaller than 4
38typedef void (*op_pixels_func)(uint8_t *block /*align width (8 or 16)*/,
39                               const uint8_t *pixels /*align 1*/,
40                               ptrdiff_t line_size, int h);
41
42/**
43 * Half-pel DSP context.
44 */
45typedef struct HpelDSPContext {
46    /**
47     * Halfpel motion compensation with rounding (a+b+1)>>1.
48     * this is an array[4][4] of motion compensation functions for 4
49     * horizontal blocksizes (8,16) and the 4 halfpel positions<br>
50     * *pixels_tab[ 0->16xH 1->8xH ][ xhalfpel + 2*yhalfpel ]
51     * @param block destination where the result is stored
52     * @param pixels source
53     * @param line_size number of bytes in a horizontal line of block
54     * @param h height
55     */
56    op_pixels_func put_pixels_tab[4][4];
57
58    /**
59     * Halfpel motion compensation with rounding (a+b+1)>>1.
60     * This is an array[4][4] of motion compensation functions for 4
61     * horizontal blocksizes (8,16) and the 4 halfpel positions<br>
62     * *pixels_tab[ 0->16xH 1->8xH ][ xhalfpel + 2*yhalfpel ]
63     * @param block destination into which the result is averaged (a+b+1)>>1
64     * @param pixels source
65     * @param line_size number of bytes in a horizontal line of block
66     * @param h height
67     */
68    op_pixels_func avg_pixels_tab[4][4];
69
70    /**
71     * Halfpel motion compensation with no rounding (a+b)>>1.
72     * this is an array[4][4] of motion compensation functions for 2
73     * horizontal blocksizes (8,16) and the 4 halfpel positions<br>
74     * *pixels_tab[ 0->16xH 1->8xH ][ xhalfpel + 2*yhalfpel ]
75     * @param block destination where the result is stored
76     * @param pixels source
77     * @param line_size number of bytes in a horizontal line of block
78     * @param h height
79     * @note The size is kept at [4][4] to match the above pixel_tabs and avoid
80     *       out of bounds reads in the motion estimation code.
81     */
82    op_pixels_func put_no_rnd_pixels_tab[4][4];
83
84    /**
85     * Halfpel motion compensation with no rounding (a+b)>>1.
86     * this is an array[4] of motion compensation functions for 1
87     * horizontal blocksize (16) and the 4 halfpel positions<br>
88     * *pixels_tab[0][ xhalfpel + 2*yhalfpel ]
89     * @param block destination into which the result is averaged (a+b)>>1
90     * @param pixels source
91     * @param line_size number of bytes in a horizontal line of block
92     * @param h height
93     */
94    op_pixels_func avg_no_rnd_pixels_tab[4];
95} HpelDSPContext;
96
97void ff_hpeldsp_init(HpelDSPContext *c, int flags);
98
99void ff_hpeldsp_init_aarch64(HpelDSPContext *c, int flags);
100void ff_hpeldsp_init_alpha(HpelDSPContext *c, int flags);
101void ff_hpeldsp_init_arm(HpelDSPContext *c, int flags);
102void ff_hpeldsp_init_ppc(HpelDSPContext *c, int flags);
103void ff_hpeldsp_init_x86(HpelDSPContext *c, int flags);
104void ff_hpeldsp_init_mips(HpelDSPContext *c, int flags);
105void ff_hpeldsp_init_loongarch(HpelDSPContext *c, int flags);
106
107#endif /* AVCODEC_HPELDSP_H */
108