/*
* QuickTime palette handling
* Copyright (c) 2001 Fabrice Bellard
* Copyright (c) 2009 Baptiste Coudurier <baptiste dot coudurier at gmail dot com>
* Copyright (c) 2015 Mats Peterson
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdint.h>
#include "avformat.h"
#include "libavutil/intreadwrite.h"
#include "qtpalette.h"
int ff_get_qtpalette(int codec_id, AVIOContext *pb, uint32_t *palette)
{
int tmp, bit_depth, color_table_id, greyscale, i;
avio_seek(pb, 82, SEEK_CUR);
/* Get the bit depth and greyscale state */
tmp = avio_rb16(pb);
bit_depth = tmp & 0x1F;
greyscale = tmp & 0x20;
/* Get the color table ID */
color_table_id = avio_rb16(pb);
/* Do not create a greyscale palette for Cinepak */
if (greyscale && codec_id == AV_CODEC_ID_CINEPAK)
return 0;
/* If the depth is 1, 2, 4, or 8 bpp, file is palettized. */
if ((bit_depth == 1 || bit_depth == 2 || bit_depth == 4 || bit_depth == 8)) {
uint32_t color_count, color_start, color_end;
uint32_t r, g, b;
/* Ignore the greyscale bit for 1-bit video and sample
* descriptions containing a color table. */
if (greyscale && bit_depth > 1 && color_table_id) {
int color_index, color_dec;
/* compute the greyscale palette */
color_count = 1 << bit_depth;
color_index = 255;
color_dec = 256 / (color_count - 1);
for (i = 0; i < color_count; i++) {
r = g = b = color_index;
palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b);
color_index -= color_dec;
if (color_index < 0)
color_index = 0;
}
} else if (color_table_id) {
/* The color table ID is non-zero. Interpret this as
* being -1, which means use the default Macintosh
* color table */
const uint8_t *color_table;
color_count = 1 << bit_depth;
if (bit_depth == 1)
color_table = ff_qt_default_palette_2;
else if (bit_depth == 2)
color_table = ff_qt_default_palette_4;
else if (bit_depth == 4)
color_table = ff_qt_default_palette_16;
else
color_table = ff_qt_default_palette_256;
for (i = 0; i < color_count; i++) {
r = color_table[i * 3 + 0];
g = color_table[i * 3 + 1];
b = color_table[i * 3 + 2];
palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b);
}
} else {
/* The color table ID is 0; the color table is in the sample
* description */
color_start = avio_rb32(pb);
avio_rb16(pb); /* color table flags */
color_end = avio_rb16(pb);
if ((color_start <= 255) && (color_end <= 255)) {
for (i = color_start; i <= color_end; i++) {
/* Each color is made of four unsigned 16 bit integers. The
* first integer is 0, the remaining integers are the red,
* the green and the blue values. We only use the top 8 bit. */
avio_skip(pb, 2);
r = avio_r8(pb);
avio_r8(pb);
g = avio_r8(pb);
avio_r8(pb);
b = avio_r8(pb);
avio_r8(pb);
palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b);
}
}
}
return 1;
}
return 0;
}