1 files changed, 153 insertions, 0 deletions
diff --git a/src/ipa/rpi/controller/rpi/agc_channel.h b/src/ipa/rpi/controller/rpi/agc_channel.h
new file mode 100644
index 00000000..4cf7233e
--- /dev/null
+++ b/src/ipa/rpi/controller/rpi/agc_channel.h
@@ -0,0 +1,153 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (C) 2023, Raspberry Pi Ltd
+ *
+ * agc_channel.h - AGC/AEC control algorithm
+ */
+#pragma once
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include <libcamera/base/utils.h>
+
+#include "../agc_status.h"
+#include "../awb_status.h"
+#include "../controller.h"
+#include "../pwl.h"
+
+/* This is our implementation of AGC. */
+
+namespace RPiController {
+
+using AgcChannelTotalExposures = std::vector<libcamera::utils::Duration>;
+
+struct AgcMeteringMode {
+	std::vector<double> weights;
+	int read(const libcamera::YamlObject &params);
+};
+
+struct AgcExposureMode {
+	std::vector<libcamera::utils::Duration> shutter;
+	std::vector<double> gain;
+	int read(const libcamera::YamlObject &params);
+};
+
+struct AgcConstraint {
+	enum class Bound { LOWER = 0,
+			   UPPER = 1 };
+	Bound bound;
+	double qLo;
+	double qHi;
+	Pwl yTarget;
+	int read(const libcamera::YamlObject &params);
+};
+
+typedef std::vector<AgcConstraint> AgcConstraintMode;
+
+struct AgcChannelConstraint {
+	enum class Bound { LOWER = 0,
+			   UPPER = 1 };
+	Bound bound;
+	unsigned int channel;
+	double factor;
+	int read(const libcamera::YamlObject &params);
+};
+
+struct AgcConfig {
+	int read(const libcamera::YamlObject &params);
+	std::map<std::string, AgcMeteringMode> meteringModes;
+	std::map<std::string, AgcExposureMode> exposureModes;
+	std::map<std::string, AgcConstraintMode> constraintModes;
+	std::vector<AgcChannelConstraint> channelConstraints;
+	Pwl yTarget;
+	double speed;
+	uint16_t startupFrames;
+	unsigned int convergenceFrames;
+	double maxChange;
+	double minChange;
+	double fastReduceThreshold;
+	double speedUpThreshold;
+	std::string defaultMeteringMode;
+	std::string defaultExposureMode;
+	std::string defaultConstraintMode;
+	double baseEv;
+	libcamera::utils::Duration defaultExposureTime;
+	double defaultAnalogueGain;
+	double stableRegion;
+	bool desaturate;
+};
+
+class AgcChannel
+{
+public:
+	AgcChannel();
+	int read(const libcamera::YamlObject &params,
+		 const Controller::HardwareConfig &hardwareConfig);
+	unsigned int getConvergenceFrames() const;
+	std::vector<double> const &getWeights() const;
+	void setEv(double ev);
+	void setFlickerPeriod(libcamera::utils::Duration flickerPeriod);
+	void setMaxShutter(libcamera::utils::Duration maxShutter);
+	void setFixedShutter(libcamera::utils::Duration fixedShutter);
+	void setFixedAnalogueGain(double fixedAnalogueGain);
+	void setMeteringMode(std::string const &meteringModeName);
+	void setExposureMode(std::string const &exposureModeName);
+	void setConstraintMode(std::string const &contraintModeName);
+	void enableAuto();
+	void disableAuto();
+	void switchMode(CameraMode const &cameraMode, Metadata *metadata);
+	void prepare(Metadata *imageMetadata);
+	void process(StatisticsPtr &stats, DeviceStatus const &deviceStatus, Metadata *imageMetadata,
+		     const AgcChannelTotalExposures &channelTotalExposures);
+
+private:
+	bool updateLockStatus(DeviceStatus const &deviceStatus);
+	AgcConfig config_;
+	void housekeepConfig();
+	void fetchCurrentExposure(DeviceStatus const &deviceStatus);
+	void fetchAwbStatus(Metadata *imageMetadata);
+	void computeGain(StatisticsPtr &statistics, Metadata *imageMetadata,
+			 double &gain, double &targetY);
+	void computeTargetExposure(double gain);
+	void filterExposure();
+	bool applyChannelConstraints(const AgcChannelTotalExposures &channelTotalExposures);
+	bool applyDigitalGain(double gain, double targetY, bool channelBound);
+	void divideUpExposure();
+	void writeAndFinish(Metadata *imageMetadata, bool desaturate);
+	libcamera::utils::Duration limitShutter(libcamera::utils::Duration shutter);
+	double limitGain(double gain) const;
+	AgcMeteringMode *meteringMode_;
+	AgcExposureMode *exposureMode_;
+	AgcConstraintMode *constraintMode_;
+	CameraMode mode_;
+	uint64_t frameCount_;
+	AwbStatus awb_;
+	struct ExposureValues {
+		ExposureValues();
+
+		libcamera::utils::Duration shutter;
+		double analogueGain;
+		libcamera::utils::Duration totalExposure;
+		libcamera::utils::Duration totalExposureNoDG; /* without digital gain */
+	};
+	ExposureValues current_; /* values for the current frame */
+	ExposureValues target_; /* calculate the values we want here */
+	ExposureValues filtered_; /* these values are filtered towards target */
+	AgcStatus status_;
+	int lockCount_;
+	DeviceStatus lastDeviceStatus_;
+	libcamera::utils::Duration lastTargetExposure_;
+	/* Below here the "settings" that applications can change. */
+	std::string meteringModeName_;
+	std::string exposureModeName_;
+	std::string constraintModeName_;
+	double ev_;
+	libcamera::utils::Duration flickerPeriod_;
+	libcamera::utils::Duration maxShutter_;
+	libcamera::utils::Duration fixedShutter_;
+	double fixedAnalogueGain_;
+};
+
+} /* namespace RPiController */