ipa: rkisp1: Introduce Black Level Correction

In order to have the proper pixel levels, apply a fixed black level
correction, based on the imx219 tuning file in RPi. The value is 4096 on
16 bits, and the pipeline for RkISP1 is on 12 bits, scale it.

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
Tested-by: Peter Griffin <peter.griffin@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/src/ipa/rkisp1/algorithms/blc.h b/src/ipa/rkisp1/algorithms/blc.h
new file mode 100644
index 00000000..69874d8f
--- /dev/null
+++ b/src/ipa/rkisp1/algorithms/blc.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021-2022, Ideas On Board
+ *
+ * blc.h - RkISP1 Black Level Correction control
+ */
+
+#pragma once
+
+#include <linux/rkisp1-config.h>
+
+#include "algorithm.h"
+
+namespace libcamera {
+
+struct IPACameraSensorInfo;
+
+namespace ipa::rkisp1::algorithms {
+
+class BlackLevelCorrection : public Algorithm
+{
+public:
+	BlackLevelCorrection() = default;
+	~BlackLevelCorrection() = default;
+
+	void prepare(IPAContext &context, rkisp1_params_cfg *params) override;
+};
+
+} /* namespace ipa::rkisp1::algorithms */
+} /* namespace libcamera */