[libcamera-devel] [PATCH v3 5/8] ipa: rkisp1: Add AF algorithm basing on common AfHillClimbing class

[Daniel Semkowicz]

Rockchip ISP AF block allows calculation of sharpness and luminance
in up to three user defined windows. If no windows are set, there are
some default settings applied for the first window and exposed through
the driver. For each frame, use the sharpness value calculated for this
default window and feed the hill climbing algorithm with them. Then set
the lens position to value calculated by the algorithm.

Signed-off-by: Daniel Semkowicz <dse at thaumatec.com>
---
 src/ipa/rkisp1/algorithms/af.cpp      | 101 ++++++++++++++++++++++++++
 src/ipa/rkisp1/algorithms/af.h        |  42 +++++++++++
 src/ipa/rkisp1/algorithms/meson.build |   1 +
 3 files changed, 144 insertions(+)
 create mode 100644 src/ipa/rkisp1/algorithms/af.cpp
 create mode 100644 src/ipa/rkisp1/algorithms/af.h

diff --git a/src/ipa/rkisp1/algorithms/af.cpp b/src/ipa/rkisp1/algorithms/af.cpp
new file mode 100644
index 00000000..c2a321cd
--- /dev/null
+++ b/src/ipa/rkisp1/algorithms/af.cpp
@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2022, Theobroma Systems
+ *
+ * af.cpp - RkISP1 AF hill climbing based control algorithm
+ */
+
+#include "af.h"
+
+/**
+ * \file af.h
+ */
+
+namespace libcamera::ipa::rkisp1::algorithms {
+
+/**
+ * \class Af
+ * \brief AF control algorithm
+ */
+
+LOG_DEFINE_CATEGORY(RkISP1Af)
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::init
+ */
+int Af::init([[maybe_unused]] IPAContext &context, const YamlObject &tuningData)
+{
+	waitFramesLens_ = tuningData["wait-frames-lens"].get<uint32_t>(1);
+
+	LOG(RkISP1Af, Debug) << "waitFramesLens_: " << waitFramesLens_;
+
+	return initBase(tuningData);
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::configure
+ */
+int Af::configure([[maybe_unused]] IPAContext &context,
+		  [[maybe_unused]] const IPACameraSensorInfo &configInfo)
+{
+	return 0;
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::queueRequest
+ */
+void Af::queueRequest([[maybe_unused]] IPAContext &context,
+		      const uint32_t frame,
+		      [[maybe_unused]] IPAFrameContext &frameContext,
+		      const ControlList &controls)
+{
+	queueRequestBase(frame, controls);
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::prepare
+ */
+void Af::prepare([[maybe_unused]] IPAContext &context,
+		 [[maybe_unused]] const uint32_t frame,
+		 [[maybe_unused]] IPAFrameContext &frameContext,
+		 [[maybe_unused]] rkisp1_params_cfg *params)
+{
+}
+
+/**
+ * \copydoc libcamera::ipa::Algorithm::process
+ */
+void Af::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
+		 [[maybe_unused]] IPAFrameContext &frameContext,
+		 const rkisp1_stat_buffer *stats,
+		 [[maybe_unused]] ControlList &metadata)
+{
+	uint32_t sharpness = stats->params.af.window[0].sum;
+	uint32_t luminance = stats->params.af.window[0].lum;
+
+	LOG(RkISP1Af, Debug) << "lensPosition: " << context.activeState.af.lensPosition
+			     << ", Sharpness: " << sharpness
+			     << ", Luminance: " << luminance;
+
+	uint32_t lensPosition = processAutofocus(sharpness);
+
+	if (lensPosition != context.activeState.af.lensPosition) {
+		context.activeState.af.lensPosition = lensPosition;
+		context.activeState.af.applyLensCtrls = true;
+		setFramesToSkip(waitFramesLens_);
+	}
+}
+
+void Af::setMeteringMode([[maybe_unused]] controls::AfMeteringEnum metering)
+{
+	LOG(RkISP1Af, Error) << __FUNCTION__ << " not implemented!";
+}
+
+void Af::setWindows([[maybe_unused]] Span<const Rectangle> windows)
+{
+	LOG(RkISP1Af, Error) << __FUNCTION__ << " not implemented!";
+}
+
+REGISTER_IPA_ALGORITHM(Af, "Af")
+
+} /* namespace libcamera::ipa::rkisp1::algorithms */
diff --git a/src/ipa/rkisp1/algorithms/af.h b/src/ipa/rkisp1/algorithms/af.h
new file mode 100644
index 00000000..882be952
--- /dev/null
+++ b/src/ipa/rkisp1/algorithms/af.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2022, Theobroma Systems
+ *
+ * af.h - RkISP1 AF hill climbing based control algorithm
+ */
+
+#pragma once
+
+#include <linux/rkisp1-config.h>
+
+#include "libipa/algorithms/af_hill_climbing.h"
+
+#include "algorithm.h"
+
+namespace libcamera::ipa::rkisp1::algorithms {
+
+class Af : public ipa::common::algorithms::AfHillClimbing, public Algorithm
+{
+public:
+	Af() = default;
+	~Af() = 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, const ControlList &controls) override;
+	void prepare(IPAContext &context, const uint32_t frame,
+		     IPAFrameContext &frameContext, rkisp1_params_cfg *params) override;
+	void process(IPAContext &context, const uint32_t frame,
+		     IPAFrameContext &frameContext, const rkisp1_stat_buffer *stats,
+		     ControlList &metadata) override;
+
+private:
+	void setMeteringMode(controls::AfMeteringEnum metering) final;
+	void setWindows(Span<const Rectangle> windows) final;
+
+	/* Wait number of frames after changing lens position */
+	uint32_t waitFramesLens_;
+};
+
+} /* namespace libcamera::ipa::rkisp1::algorithms */
diff --git a/src/ipa/rkisp1/algorithms/meson.build b/src/ipa/rkisp1/algorithms/meson.build
index 93a48329..ab7e44f3 100644
--- a/src/ipa/rkisp1/algorithms/meson.build
+++ b/src/ipa/rkisp1/algorithms/meson.build
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: CC0-1.0
 
 rkisp1_ipa_algorithms = files([
+    'af.cpp',
     'agc.cpp',
     'awb.cpp',
     'blc.cpp',
-- 
2.39.0