| /* | |
| * 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 | |
| */ | |
| /** | |
| * 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); | |