| 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 | */ |
| 29 | typedef struct AVDCT { |
| 30 | const AVClass *av_class; |
| 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 | */ |
| 57 | int dct_algo; |
| 58 | |
| 59 | /** |
| 60 | * IDCT algorithm. |
| 61 | * must use AVOptions to set this field. |
| 62 | */ |
| 63 | int idct_algo; |
| 64 | |
| 65 | void (*get_pixels)(int16_t *block /* align 16 */, |
| 66 | const uint8_t *pixels /* align 8 */, |
| 67 | ptrdiff_t line_size); |
| 68 | } AVDCT; |
| 69 | |
| 70 | /** |
| 71 | * Allocates a AVDCT context. |
| 72 | * This needs to be initialized with avcodec_dct_init() after optionally |
| 73 | * configuring it with AVOptions. |
| 74 | * |
| 75 | * To free it use av_free() |
| 76 | */ |
| 77 | AVDCT *avcodec_dct_alloc(void); |
| 78 | int avcodec_dct_init(AVDCT *); |
| 79 | |
| 80 | const AVClass *avcodec_dct_get_class(void); |
| 81 | |
| 82 | #endif /* AVCODEC_AVDCT_H */ |