FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/png.c
Date: 2021-09-26 18:22:30
Exec Total Coverage
Lines: 18 19 94.7%
Branches: 5 6 83.3%

Line Branch Exec Source
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 #include <stdint.h>
23 #include "libavutil/mem.h"
24 #include "png.h"
25
26 /* Mask to determine which y pixels are valid in a pass */
27 const uint8_t ff_png_pass_ymask[NB_PASSES] = {
28 0x80, 0x80, 0x08, 0x88, 0x22, 0xaa, 0x55,
29 };
30
31 /* minimum x value */
32 static const uint8_t ff_png_pass_xmin[NB_PASSES] = {
33 0, 4, 0, 2, 0, 1, 0
34 };
35
36 /* x shift to get row width */
37 static const uint8_t ff_png_pass_xshift[NB_PASSES] = {
38 3, 3, 2, 2, 1, 1, 0
39 };
40
41 1496 void *ff_png_zalloc(void *opaque, unsigned int items, unsigned int size)
42 {
43 1496 return av_calloc(items, size);
44 }
45
46 1496 void ff_png_zfree(void *opaque, void *ptr)
47 {
48 1496 av_free(ptr);
49 1496 }
50
51 630 int ff_png_get_nb_channels(int color_type)
52 {
53 int channels;
54 630 channels = 1;
55
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630 if ((color_type & (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)) ==
56 PNG_COLOR_MASK_COLOR)
57 564 channels = 3;
58
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630 if (color_type & PNG_COLOR_MASK_ALPHA)
59 87 channels++;
60 630 return channels;
61 }
62
63 /* compute the row size of an interleaved pass */
64 28 int ff_png_pass_row_size(int pass, int bits_per_pixel, int width)
65 {
66 int shift, xmin, pass_width;
67
68 28 xmin = ff_png_pass_xmin[pass];
69
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28 if (width <= xmin)
70 return 0;
71 28 shift = ff_png_pass_xshift[pass];
72 28 pass_width = (width - xmin + (1 << shift) - 1) >> shift;
73 28 return (pass_width * bits_per_pixel + 7) >> 3;
74 }
75