| 1 | /* |
| 2 | * PNG image format |
| 3 | * Copyright (c) 2003 Fabrice Bellard |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #ifndef AVCODEC_PNG_H |
| 23 | #define AVCODEC_PNG_H |
| 24 | |
| 25 | #include <stdint.h> |
| 26 | |
| 27 | #define PNG_COLOR_MASK_PALETTE 1 |
| 28 | #define PNG_COLOR_MASK_COLOR 2 |
| 29 | #define PNG_COLOR_MASK_ALPHA 4 |
| 30 | |
| 31 | #define PNG_COLOR_TYPE_GRAY 0 |
| 32 | #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) |
| 33 | #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) |
| 34 | #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) |
| 35 | #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) |
| 36 | |
| 37 | #define PNG_FILTER_TYPE_LOCO 64 |
| 38 | #define PNG_FILTER_VALUE_NONE 0 |
| 39 | #define PNG_FILTER_VALUE_SUB 1 |
| 40 | #define PNG_FILTER_VALUE_UP 2 |
| 41 | #define PNG_FILTER_VALUE_AVG 3 |
| 42 | #define PNG_FILTER_VALUE_PAETH 4 |
| 43 | #define PNG_FILTER_VALUE_MIXED 5 |
| 44 | |
| 45 | #define PNG_IHDR 0x0001 |
| 46 | #define PNG_IDAT 0x0002 |
| 47 | #define PNG_ALLIMAGE 0x0004 |
| 48 | #define PNG_PLTE 0x0008 |
| 49 | |
| 50 | #define NB_PASSES 7 |
| 51 | |
| 52 | #define PNGSIG 0x89504e470d0a1a0a |
| 53 | #define MNGSIG 0x8a4d4e470d0a1a0a |
| 54 | |
| 55 | /* Mask to determine which y pixels are valid in a pass */ |
| 56 | extern const uint8_t ff_png_pass_ymask[NB_PASSES]; |
| 57 | |
| 58 | void *ff_png_zalloc(void *opaque, unsigned int items, unsigned int size); |
| 59 | |
| 60 | void ff_png_zfree(void *opaque, void *ptr); |
| 61 | |
| 62 | int ff_png_get_nb_channels(int color_type); |
| 63 | |
| 64 | /* compute the row size of an interleaved pass */ |
| 65 | int ff_png_pass_row_size(int pass, int bits_per_pixel, int width); |
| 66 | |
| 67 | void ff_add_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top, int w, int bpp); |
| 68 | |
| 69 | #endif /* AVCODEC_PNG_H */ |