1 files changed, 89 insertions, 0 deletions
diff --git a/src/ipa/rpi/controller/rpi/geq.cpp b/src/ipa/rpi/controller/rpi/geq.cpp
new file mode 100644
index 00000000..510870e9
--- /dev/null
+++ b/src/ipa/rpi/controller/rpi/geq.cpp
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (C) 2019, Raspberry Pi Ltd
+ *
+ * geq.cpp - GEQ (green equalisation) control algorithm
+ */
+
+#include <libcamera/base/log.h>
+
+#include "../device_status.h"
+#include "../lux_status.h"
+#include "../pwl.h"
+
+#include "geq.h"
+
+using namespace RPiController;
+using namespace libcamera;
+
+LOG_DEFINE_CATEGORY(RPiGeq)
+
+/*
+ * We use the lux status so that we can apply stronger settings in darkness (if
+ * necessary).
+ */
+
+#define NAME "rpi.geq"
+
+Geq::Geq(Controller *controller)
+	: Algorithm(controller)
+{
+}
+
+char const *Geq::name() const
+{
+	return NAME;
+}
+
+int Geq::read(const libcamera::YamlObject &params)
+{
+	config_.offset = params["offset"].get<uint16_t>(0);
+	config_.slope = params["slope"].get<double>(0.0);
+	if (config_.slope < 0.0 || config_.slope >= 1.0) {
+		LOG(RPiGeq, Error) << "Bad slope value";
+		return -EINVAL;
+	}
+
+	if (params.contains("strength")) {
+		int ret = config_.strength.read(params["strength"]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+void Geq::prepare(Metadata *imageMetadata)
+{
+	LuxStatus luxStatus = {};
+	luxStatus.lux = 400;
+	if (imageMetadata->get("lux.status", luxStatus))
+		LOG(RPiGeq, Warning) << "no lux data found";
+	DeviceStatus deviceStatus;
+	deviceStatus.analogueGain = 1.0; /* in case not found */
+	if (imageMetadata->get("device.status", deviceStatus))
+		LOG(RPiGeq, Warning)
+			<< "no device metadata - use analogue gain of 1x";
+	GeqStatus geqStatus = {};
+	double strength = config_.strength.empty()
+			? 1.0
+			: config_.strength.eval(config_.strength.domain().clip(luxStatus.lux));
+	strength *= deviceStatus.analogueGain;
+	double offset = config_.offset * strength;
+	double slope = config_.slope * strength;
+	geqStatus.offset = std::min(65535.0, std::max(0.0, offset));
+	geqStatus.slope = std::min(.99999, std::max(0.0, slope));
+	LOG(RPiGeq, Debug)
+		<< "offset " << geqStatus.offset << " slope "
+		<< geqStatus.slope << " (analogue gain "
+		<< deviceStatus.analogueGain << " lux "
+		<< luxStatus.lux << ")";
+	imageMetadata->set("geq.status", geqStatus);
+}
+
+/* Register algorithm with the system. */
+static Algorithm *create(Controller *controller)
+{
+	return (Algorithm *)new Geq(controller);
+}
+static RegisterAlgorithm reg(NAME, &create);