[PATCH v4 2/6] ipa: rkisp1: awb: Load white balance gains from tuning file

[Stefan Klug]

For the implementation of a manual colour temperature setting, it is
necessary to read predefined colour gains per colour temperature from
the tuning file. Implement this in a backwards compatible way. If no
gains are contained in the tuning file, loading just continues as
before.

Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
---
 src/ipa/rkisp1/algorithms/awb.cpp | 18 ++++++++++++++++++
 src/ipa/rkisp1/algorithms/awb.h   |  6 ++++++
 2 files changed, 24 insertions(+)

diff --git a/src/ipa/rkisp1/algorithms/awb.cpp b/src/ipa/rkisp1/algorithms/awb.cpp
index 4ccafd48dedd..c23f749c192b 100644
--- a/src/ipa/rkisp1/algorithms/awb.cpp
+++ b/src/ipa/rkisp1/algorithms/awb.cpp
@@ -39,6 +39,24 @@ Awb::Awb()
 {
 }
 
+/**
+ * \copydoc libcamera::ipa::Algorithm::init
+ */
+int Awb::init([[maybe_unused]] IPAContext &context, const YamlObject &tuningData)
+{
+	MatrixInterpolator<double, 2, 1> gains;
+	int ret = gains.readYaml(tuningData["gains"], "ct", "gains");
+	if (ret < 0)
+		LOG(RkISP1Awb, Warning)
+			<< "Failed to parse 'gains' "
+			<< "parameter from tuning file; "
+			<< "rgb gains will not be set based on colour temperature";
+	else
+		gains_ = gains;
+
+	return 0;
+}
+
 /**
  * \copydoc libcamera::ipa::Algorithm::configure
  */
diff --git a/src/ipa/rkisp1/algorithms/awb.h b/src/ipa/rkisp1/algorithms/awb.h
index 06c92896e2dc..a010e6d1cb3c 100644
--- a/src/ipa/rkisp1/algorithms/awb.h
+++ b/src/ipa/rkisp1/algorithms/awb.h
@@ -7,6 +7,10 @@
 
 #pragma once
 
+#include <optional>
+
+#include "libipa/matrix_interpolator.h"
+
 #include "algorithm.h"
 
 namespace libcamera {
@@ -19,6 +23,7 @@ public:
 	Awb();
 	~Awb() = default;
 
+	int init(IPAContext &context, const YamlObject &tuningData) override;
 	int configure(IPAContext &context, const IPACameraSensorInfo &configInfo) override;
 	void queueRequest(IPAContext &context, const uint32_t frame,
 			  IPAFrameContext &frameContext,
@@ -34,6 +39,7 @@ public:
 private:
 	uint32_t estimateCCT(double red, double green, double blue);
 
+	std::optional<MatrixInterpolator<double, 2, 1>> gains_;
 	bool rgbMode_;
 };
 
-- 
2.43.0