src/ipa/raspberrypi/controller/rpi/alsc.hpp


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/* SPDX-License-Identifier: BSD-2-Clause */
/*
 * Copyright (C) 2019, Raspberry Pi (Trading) Limited
 *
 * alsc.hpp - ALSC (auto lens shading correction) control algorithm
 */
#pragma once

#include <mutex>
#include <condition_variable>
#include <thread>

#include "../algorithm.hpp"
#include "../alsc_status.h"

namespace RPiController {

// Algorithm to generate automagic LSC (Lens Shading Correction) tables.

struct AlscCalibration {
	double ct;
	double table[ALSC_CELLS_X * ALSC_CELLS_Y];
};

struct AlscConfig {
	// Only repeat the ALSC calculation every "this many" frames
	uint16_t frame_period;
	// number of initial frames for which speed taken as 1.0 (maximum)
	uint16_t startup_frames;
	// IIR filter speed applied to algorithm results
	double speed;
	double sigma_Cr;
	double sigma_Cb;
	double min_count;
	uint16_t min_G;
	double omega;
	uint32_t n_iter;
	double luminance_lut[ALSC_CELLS_X * ALSC_CELLS_Y];
	double luminance_strength;
	std::vector<AlscCalibration> calibrations_Cr;
	std::vector<AlscCalibration> calibrations_Cb;
	double default_ct; // colour temperature if no metadata found
	double threshold; // iteration termination threshold
	double lambda_bound; // upper/lower bound for lambda from a value of 1
};