2 * QuickTime palette handling
3 * Copyright (c) 2001 Fabrice Bellard
4 * Copyright (c) 2009 Baptiste Coudurier <baptiste dot coudurier at gmail dot com>
5 * Copyright (c) 2015 Mats Peterson
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #include "libavutil/intreadwrite.h"
29 #include "qtpalette.h"
31 int ff_get_qtpalette(int codec_id, AVIOContext *pb, uint32_t *palette)
33 int tmp, bit_depth, color_table_id, greyscale, i;
35 avio_seek(pb, 82, SEEK_CUR);
37 /* Get the bit depth and greyscale state */
39 bit_depth = tmp & 0x1F;
40 greyscale = tmp & 0x20;
42 /* Get the color table ID */
43 color_table_id = avio_rb16(pb);
45 /* Do not create a greyscale palette for Cinepak */
46 if (greyscale && codec_id == AV_CODEC_ID_CINEPAK)
49 /* If the depth is 1, 2, 4, or 8 bpp, file is palettized. */
50 if ((bit_depth == 1 || bit_depth == 2 || bit_depth == 4 || bit_depth == 8)) {
51 uint32_t color_count, color_start, color_end;
54 /* Ignore the greyscale bit for 1-bit video and sample
55 * descriptions containing a color table. */
56 if (greyscale && bit_depth > 1 && color_table_id) {
57 int color_index, color_dec;
58 /* compute the greyscale palette */
59 color_count = 1 << bit_depth;
61 color_dec = 256 / (color_count - 1);
62 for (i = 0; i < color_count; i++) {
63 r = g = b = color_index;
64 palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b);
65 color_index -= color_dec;
69 } else if (color_table_id) {
70 /* The color table ID is non-zero. Interpret this as
71 * being -1, which means use the default Macintosh
73 const uint8_t *color_table;
74 color_count = 1 << bit_depth;
76 color_table = ff_qt_default_palette_2;
77 else if (bit_depth == 2)
78 color_table = ff_qt_default_palette_4;
79 else if (bit_depth == 4)
80 color_table = ff_qt_default_palette_16;
82 color_table = ff_qt_default_palette_256;
83 for (i = 0; i < color_count; i++) {
84 r = color_table[i * 3 + 0];
85 g = color_table[i * 3 + 1];
86 b = color_table[i * 3 + 2];
87 palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b);
90 /* The color table ID is 0; the color table is in the sample
92 color_start = avio_rb32(pb);
93 avio_rb16(pb); /* color table flags */
94 color_end = avio_rb16(pb);
95 if ((color_start <= 255) && (color_end <= 255)) {
96 for (i = color_start; i <= color_end; i++) {
97 /* each A, R, G, or B component is 16 bits;
98 * only use the top 8 bits */
107 palette[i] = (a << 24 ) | (r << 16) | (g << 8) | (b);