libcamera: ipa: Raspberry Pi IPA

Initial implementation of the Raspberry Pi (BCM2835) libcamera IPA and
associated libraries.

All code is licensed under the BSD-2-Clause terms.
Copyright (c) 2019-2020 Raspberry Pi Trading Ltd.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

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

@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (C) 2019, Raspberry Pi (Trading) Limited
+ *
+ * geq.hpp - GEQ (green equalisation) control algorithm
+ */
+#pragma once
+
+#include "../algorithm.hpp"
+#include "../geq_status.h"
+
+namespace RPi {
+
+// Back End algorithm to apply appropriate GEQ settings.
+
+struct GeqConfig {
+	uint16_t offset;
+	double slope;
+	Pwl strength; // lux to strength factor
+};
+
+class Geq : public Algorithm
+{
+public:
+	Geq(Controller *controller);
+	char const *Name() const override;
+	void Read(boost::property_tree::ptree const &params) override;
+	void Prepare(Metadata *image_metadata) override;
+
+private:
+	GeqConfig config_;
+};
+
+} // namespace RPi