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avdct.h
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/*
* 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
*/
#ifndef AVCODEC_AVDCT_H
#define AVCODEC_AVDCT_H
#include "libavutil/opt.h"
/**
* AVDCT context.
* @note function pointers can be NULL if the specific features have been
* disabled at build time.
*/
typedef struct AVDCT {
const AVClass *av_class;
void (*idct)(int16_t *block /* align 16 */);
/**
* IDCT input permutation.
* Several optimized IDCTs need a permutated input (relative to the
* normal order of the reference IDCT).
* This permutation must be performed before the idct_put/add.
* Note, normally this can be merged with the zigzag/alternate scan<br>
* An example to avoid confusion:
* - (->decode coeffs -> zigzag reorder -> dequant -> reference IDCT -> ...)
* - (x -> reference DCT -> reference IDCT -> x)
* - (x -> reference DCT -> simple_mmx_perm = idct_permutation
* -> simple_idct_mmx -> x)
* - (-> decode coeffs -> zigzag reorder -> simple_mmx_perm -> dequant
* -> simple_idct_mmx -> ...)
*/
uint8_t idct_permutation[64];
void (*fdct)(int16_t *block /* align 16 */);
/**
* DCT algorithm.
* must use AVOptions to set this field.
*/
int dct_algo;
/**
* IDCT algorithm.
* must use AVOptions to set this field.
*/
int idct_algo;
void (*get_pixels)(int16_t *block /* align 16 */,
const uint8_t *pixels /* align 8 */,
ptrdiff_t line_size);
int bits_per_sample;
void (*get_pixels_unaligned)(int16_t *block /* align 16 */,
const uint8_t *pixels,
ptrdiff_t line_size);
} AVDCT;
/**
* Allocates a AVDCT context.
* This needs to be initialized with avcodec_dct_init() after optionally
* configuring it with AVOptions.
*
* To free it use av_free()
*/
AVDCT *avcodec_dct_alloc(void);
int avcodec_dct_init(AVDCT *);
const AVClass *avcodec_dct_get_class(void);
#endif /* AVCODEC_AVDCT_H */
avcodec_dct_alloc
AVDCT * avcodec_dct_alloc(void)
Allocates a AVDCT context.
avcodec_dct_init
int avcodec_dct_init(AVDCT *)
avcodec_dct_get_class
const AVClass * avcodec_dct_get_class(void)
opt.h
AVOptions.
AVClass
Describe the class of an AVClass context structure.
Definition log.h:66
AVDCT
AVDCT context.
Definition avdct.h:29
AVDCT::idct_permutation
uint8_t idct_permutation[64]
IDCT input permutation.
Definition avdct.h:48
AVDCT::get_pixels
void(* get_pixels)(int16_t *block, const uint8_t *pixels, ptrdiff_t line_size)
Definition avdct.h:65
AVDCT::idct
void(* idct)(int16_t *block)
Definition avdct.h:32
AVDCT::av_class
const AVClass * av_class
Definition avdct.h:30
AVDCT::bits_per_sample
int bits_per_sample
Definition avdct.h:69
AVDCT::fdct
void(* fdct)(int16_t *block)
Definition avdct.h:50
AVDCT::get_pixels_unaligned
void(* get_pixels_unaligned)(int16_t *block, const uint8_t *pixels, ptrdiff_t line_size)
Definition avdct.h:71
AVDCT::idct_algo
int idct_algo
IDCT algorithm.
Definition avdct.h:63
AVDCT::dct_algo
int dct_algo
DCT algorithm.
Definition avdct.h:57