3 * Copyright (c) 2003 Fabrice Bellard
5 * This file is part of FFmpeg.
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.
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.
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
30 #define PNG_COLOR_MASK_PALETTE 1
31 #define PNG_COLOR_MASK_COLOR 2
32 #define PNG_COLOR_MASK_ALPHA 4
34 #define PNG_COLOR_TYPE_GRAY 0
35 #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
36 #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
37 #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
38 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
40 #define PNG_FILTER_TYPE_LOCO 64
41 #define PNG_FILTER_VALUE_NONE 0
42 #define PNG_FILTER_VALUE_SUB 1
43 #define PNG_FILTER_VALUE_UP 2
44 #define PNG_FILTER_VALUE_AVG 3
45 #define PNG_FILTER_VALUE_PAETH 4
46 #define PNG_FILTER_VALUE_MIXED 5
48 #define PNG_IHDR 0x0001
49 #define PNG_IDAT 0x0002
50 #define PNG_ALLIMAGE 0x0004
51 #define PNG_PLTE 0x0008
55 extern const uint8_t ff_pngsig[8];
56 extern const uint8_t ff_mngsig[8];
58 /* Mask to determine which y pixels are valid in a pass */
59 extern const uint8_t ff_png_pass_ymask[NB_PASSES];
61 /* Mask to determine which pixels are valid in a pass */
62 extern const uint8_t ff_png_pass_mask[NB_PASSES];
64 void *ff_png_zalloc(void *opaque, unsigned int items, unsigned int size);
66 void ff_png_zfree(void *opaque, void *ptr);
68 int ff_png_get_nb_channels(int color_type);
70 /* compute the row size of an interleaved pass */
71 int ff_png_pass_row_size(int pass, int bits_per_pixel, int width);
73 void ff_add_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top, int w, int bpp);
75 typedef struct PNGDecContext {
76 const uint8_t *bytestream;
77 const uint8_t *bytestream_start;
78 const uint8_t *bytestream_end;
79 AVFrame picture1, picture2;
80 AVFrame *current_picture, *last_picture;
95 uint32_t palette[256];
100 int crow_size; /* compressed row size (include filter type) */
101 int row_size; /* decompressed row size */
102 int pass_row_size; /* decompress row size of the current pass */
106 void (*add_bytes_l2)(uint8_t *dst, uint8_t *src1, uint8_t *src2, int w);
107 void (*add_paeth_prediction)(uint8_t *dst, uint8_t *src, uint8_t *top, int w, int bpp);
110 void ff_png_init_mmx(PNGDecContext *s);
112 #endif /* AVCODEC_PNG_H */