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libavcodec
png.h
Go to the documentation of this file.
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/*
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* PNG image format
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* Copyright (c) 2003 Fabrice Bellard
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*
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* This file is part of Libav.
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*
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* Libav is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* Libav is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef AVCODEC_PNG_H
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#define AVCODEC_PNG_H
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#include <stdint.h>
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#define PNG_COLOR_MASK_PALETTE 1
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#define PNG_COLOR_MASK_COLOR 2
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#define PNG_COLOR_MASK_ALPHA 4
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#define PNG_COLOR_TYPE_GRAY 0
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#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
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#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
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#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
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#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
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#define PNG_FILTER_TYPE_LOCO 64
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#define PNG_FILTER_VALUE_NONE 0
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#define PNG_FILTER_VALUE_SUB 1
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#define PNG_FILTER_VALUE_UP 2
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#define PNG_FILTER_VALUE_AVG 3
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#define PNG_FILTER_VALUE_PAETH 4
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#define PNG_FILTER_VALUE_MIXED 5
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#define PNG_IHDR 0x0001
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#define PNG_IDAT 0x0002
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#define PNG_ALLIMAGE 0x0004
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#define PNG_PLTE 0x0008
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#define NB_PASSES 7
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extern
const
uint8_t
ff_pngsig
[8];
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extern
const
uint8_t
ff_mngsig
[8];
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/* Mask to determine which y pixels are valid in a pass */
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extern
const
uint8_t
ff_png_pass_ymask
[
NB_PASSES
];
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/* Mask to determine which pixels are valid in a pass */
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extern
const
uint8_t
ff_png_pass_mask
[
NB_PASSES
];
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void
*
ff_png_zalloc
(
void
*opaque,
unsigned
int
items,
unsigned
int
size
);
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void
ff_png_zfree
(
void
*opaque,
void
*ptr);
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int
ff_png_get_nb_channels
(
int
color_type);
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/* compute the row size of an interleaved pass */
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int
ff_png_pass_row_size
(
int
pass
,
int
bits_per_pixel,
int
width
);
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void
ff_add_png_paeth_prediction
(uint8_t *dst, uint8_t *src, uint8_t *top,
int
w,
int
bpp);
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#endif
/* AVCODEC_PNG_H */