/*  * Copyright (C) 2024 Niklas Haas  *  * 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 SWSCALE_CMS_H#define SWSCALE_CMS_H #include <stdbool.h> #include "libavutil/csp.h" #include "csputils.h"#include "swscale.h"#include "utils.h" /* Minimum, maximum, and default knee point for perceptual tone mapping [0,1] */#define PERCEPTUAL_KNEE_MIN 0.10f#define PERCEPTUAL_KNEE_MAX 0.80f#define PERCEPTUAL_KNEE_DEF 0.40f /* Ratio between source average and target average. */#define PERCEPTUAL_ADAPTATION 0.40f /* (Relative) chromaticity protection zone for perceptual mapping [0,1] */#define PERCEPTUAL_DEADZONE 0.30f /* Contrast setting for perceptual tone mapping. [0,1.5] */#define PERCEPTUAL_CONTRAST 0.50f /* Tuning constants for overriding the contrast near extremes */#define SLOPE_TUNING 1.50f /* [0,10] */#define SLOPE_OFFSET 0.20f /* [0,1] */ /* Strength of the perceptual saturation mapping component [0,1] */#define PERCEPTUAL_STRENGTH 0.80f /* Knee point to use for perceptual soft clipping [0,1] */#define SOFTCLIP_KNEE 0.70f /* I vs C curve gamma to use for colorimetric clipping [0,10] */#define COLORIMETRIC_GAMMA 1.80f /* Struct describing a color mapping operation */typedef struct SwsColorMap {    SwsColor src;    SwsColor dst;    SwsIntent intent;} SwsColorMap; /** * Returns true if the given color map is a semantic no-op - that is, * the overall RGB end to end transform would an identity mapping. */bool ff_sws_color_map_noop(const SwsColorMap *map); /** * Generates a single end-to-end color mapping 3DLUT embedding a static tone * mapping curve. * * Returns 0 on success, or a negative error code on failure. */int ff_sws_color_map_generate_static(v3u16_t *lut, int size, const SwsColorMap *map); /** * Generates a split pair of 3DLUTS, going to IPT and back, allowing an * arbitrary dynamic EETF to be nestled in between these two operations. * * See ff_sws_tone_map_generate(). * * Returns 0 on success, or a negative error code on failure. */int ff_sws_color_map_generate_dynamic(v3u16_t *input, v3u16_t *output,                                      int size_input, int size_I, int size_PT,                                      const SwsColorMap *map); /** * Generate a 1D LUT of size `size` adapting intensity (I) levels from the * source to the destination color space. The LUT is normalized to the * relevant intensity range directly. The second channel of each entry returns * the corresponding 15-bit scaling factor for the P/T channels. The scaling * factor k may be applied as `(1 << 15) - k + (PT * k >> 15)`. * * This is designed to be used with sws_gamut_map_generate_dynamic(). * * Returns 0 on success, or a negative error code on failure. */void ff_sws_tone_map_generate(v2u16_t *lut, int size, const SwsColorMap *map); #endif // SWSCALE_GAMUT_MAPPING_H