| /* |
| * Copyright (c) 2020 Björn Ottosson |
| * Copyright (c) 2022 Clément Bœsch <u pkh me> |
| * |
| * 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 |
| */ |
| |
| #ifndef AVFILTER_PALETTE_H |
| #define AVFILTER_PALETTE_H |
| |
| #include <math.h> |
| #include <stdint.h> |
| |
| #include "libavutil/attributes.h" |
| |
| struct Lab { |
| int32_t L, a, b; |
| }; |
| |
| /** |
| * Map sRGB 8-bit color component to a 16-bit linear value (gamma |
| * expand from electrical to optical value). |
| */ |
| int32_t ff_srgb_u8_to_linear_int(uint8_t x); |
| |
| /** |
| * Map a 16-bit linear value to a sRGB 8-bit color component (gamma |
| * compressed from optical to electrical value). |
| */ |
| uint8_t ff_linear_int_to_srgb_u8(int32_t x); |
| |
| /** |
| * sRGB (non-linear) to OkLab conversion |
| * @see https://bottosson.github.io/posts/oklab/ |
| */ |
| struct Lab ff_srgb_u8_to_oklab_int(uint32_t srgb); |
| |
| /** |
| * OkLab to sRGB (non-linear) conversion |
| * @see https://bottosson.github.io/posts/oklab/ |
| */ |
| uint32_t ff_oklab_int_to_srgb_u8(struct Lab c); |
| |
| /* |
| * lowbias32 hashing from https://nullprogram.com/blog/2018/07/31/ |
| */ |
| uint32_t ff_lowbias32(uint32_t x); |
| |
| #endif /* AVFILTER_PALETTE_H */ |