FFmpeg 5.1.6
avdct.h
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1/*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19#ifndef AVCODEC_AVDCT_H
20#define AVCODEC_AVDCT_H
21
22#include "libavutil/opt.h"
23
24/**
25 * AVDCT context.
26 * @note function pointers can be NULL if the specific features have been
27 * disabled at build time.
28 */
29typedef struct AVDCT {
31
32 void (*idct)(int16_t *block /* align 16 */);
33
34 /**
35 * IDCT input permutation.
36 * Several optimized IDCTs need a permutated input (relative to the
37 * normal order of the reference IDCT).
38 * This permutation must be performed before the idct_put/add.
39 * Note, normally this can be merged with the zigzag/alternate scan<br>
40 * An example to avoid confusion:
41 * - (->decode coeffs -> zigzag reorder -> dequant -> reference IDCT -> ...)
42 * - (x -> reference DCT -> reference IDCT -> x)
43 * - (x -> reference DCT -> simple_mmx_perm = idct_permutation
44 * -> simple_idct_mmx -> x)
45 * - (-> decode coeffs -> zigzag reorder -> simple_mmx_perm -> dequant
46 * -> simple_idct_mmx -> ...)
47 */
48 uint8_t idct_permutation[64];
49
50 void (*fdct)(int16_t *block /* align 16 */);
51
52
53 /**
54 * DCT algorithm.
55 * must use AVOptions to set this field.
56 */
58
59 /**
60 * IDCT algorithm.
61 * must use AVOptions to set this field.
62 */
64
65 void (*get_pixels)(int16_t *block /* align 16 */,
66 const uint8_t *pixels /* align 8 */,
67 ptrdiff_t line_size);
68
70
71 void (*get_pixels_unaligned)(int16_t *block /* align 16 */,
72 const uint8_t *pixels,
73 ptrdiff_t line_size);
74} AVDCT;
75
76/**
77 * Allocates a AVDCT context.
78 * This needs to be initialized with avcodec_dct_init() after optionally
79 * configuring it with AVOptions.
80 *
81 * To free it use av_free()
82 */
85
87
88#endif /* AVCODEC_AVDCT_H */
AVDCT * avcodec_dct_alloc(void)
Allocates a AVDCT context.
int avcodec_dct_init(AVDCT *)
const AVClass * avcodec_dct_get_class(void)
AVOptions.
Describe the class of an AVClass context structure.
Definition: log.h:66
AVDCT context.
Definition: avdct.h:29
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: avdct.h:48
void(* get_pixels)(int16_t *block, const uint8_t *pixels, ptrdiff_t line_size)
Definition: avdct.h:65
void(* idct)(int16_t *block)
Definition: avdct.h:32
const AVClass * av_class
Definition: avdct.h:30
int bits_per_sample
Definition: avdct.h:69
void(* fdct)(int16_t *block)
Definition: avdct.h:50
void(* get_pixels_unaligned)(int16_t *block, const uint8_t *pixels, ptrdiff_t line_size)
Definition: avdct.h:71
int idct_algo
IDCT algorithm.
Definition: avdct.h:63
int dct_algo
DCT algorithm.
Definition: avdct.h:57