[libcamera-devel] [PATCH 05/11] libcamera: software_isp: Add Debayer base class

[Hans de Goede]

Add a base class for debayer implementations. This is intended to be
suitable for both GPU (or otherwise) accelerated debayer implementations
as well as CPU based debayering.

Co-authored-by: Andrey Konovalov <andrey.konovalov at linaro.org>
Signed-off-by: Andrey Konovalov <andrey.konovalov at linaro.org>
Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
 .../libcamera/internal/software_isp/debayer.h | 90 +++++++++++++++++++
 .../internal/software_isp/debayer_params.h    | 24 +++++
 .../internal/software_isp/meson.build         |  2 +
 src/libcamera/software_isp/debayer.cpp        | 22 +++++
 src/libcamera/software_isp/meson.build        |  1 +
 5 files changed, 139 insertions(+)
 create mode 100644 include/libcamera/internal/software_isp/debayer.h
 create mode 100644 include/libcamera/internal/software_isp/debayer_params.h
 create mode 100644 src/libcamera/software_isp/debayer.cpp

diff --git a/include/libcamera/internal/software_isp/debayer.h b/include/libcamera/internal/software_isp/debayer.h
new file mode 100644
index 00000000..206bc2ac
--- /dev/null
+++ b/include/libcamera/internal/software_isp/debayer.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2023, Linaro Ltd
+ * Copyright (C) 2023, Red Hat Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede at redhat.com> 
+ *
+ * debayer.h - debayering base class
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+#include <libcamera/base/log.h>
+#include <libcamera/base/signal.h>
+
+#include <libcamera/geometry.h>
+#include <libcamera/stream.h>
+
+#include "libcamera/internal/software_isp/debayer_params.h"
+
+namespace libcamera {
+
+class FrameBuffer;
+
+LOG_DECLARE_CATEGORY(Debayer)
+
+class Debayer
+{
+public:
+	virtual ~Debayer() = 0;
+
+	/*
+	 * Setup the Debayer object according to the passed in parameters.
+	 * Return 0 on success, a negative errno value on failure
+	 * (unsupported parameters).
+	 */
+	virtual int configure(const StreamConfiguration &inputCfg,
+			      const std::vector<std::reference_wrapper<StreamConfiguration>> &outputCfgs) = 0;
+
+	/*
+	 * Get width and height at which the bayer-pattern repeats.
+	 * Return pattern-size or an empty Size for an unsupported inputFormat.
+	 */
+	virtual Size patternSize(PixelFormat inputFormat) = 0;
+
+	virtual std::vector<PixelFormat> formats(PixelFormat inputFormat) = 0;
+	virtual std::tuple<unsigned int, unsigned int>
+		strideAndFrameSize(const PixelFormat &outputFormat, const Size &size) = 0;
+
+	/*
+	 * Note DebayerParams is passed by value deliberately so that a copy is passed
+	 * when this is run in another thread to invokeMethod.
+	 */
+	virtual void process(FrameBuffer *input, FrameBuffer *output, DebayerParams params) = 0;
+
+	/* sizes() - Get supported output sizes for given input fmt + size */
+	SizeRange sizes(PixelFormat inputFormat, const Size &inputSize)
+	{
+		Size pattern_size = patternSize(inputFormat);
+
+		if (pattern_size.isNull())
+			return {};
+
+		/*
+		 * For debayer interpolation a border of pattern-height x pattern-width
+		 * is kept around the entire image. Combined with a minimum-size of
+		 * pattern-height x pattern-width this means the input-size needs to be
+		 * at least (3 * pattern-height) x (3 * pattern-width).
+		 */
+		if (inputSize.width < (3 * pattern_size.width) ||
+		    inputSize.height < (3 * pattern_size.height)) {
+			LOG(Debayer, Warning)
+				<< "Input format size too small: " << inputSize.toString();
+			return {};
+		}
+
+		return SizeRange(Size(pattern_size.width, pattern_size.height),
+				 Size((inputSize.width - 2 * pattern_size.width) & ~(pattern_size.width - 1),
+				      (inputSize.height - 2 * pattern_size.height) & ~(pattern_size.height - 1)),
+				 pattern_size.width, pattern_size.height);
+	}
+
+	Signal<FrameBuffer *> inputBufferReady;
+	Signal<FrameBuffer *> outputBufferReady;
+};
+
+} /* namespace libcamera */
diff --git a/include/libcamera/internal/software_isp/debayer_params.h b/include/libcamera/internal/software_isp/debayer_params.h
new file mode 100644
index 00000000..885d3605
--- /dev/null
+++ b/include/libcamera/internal/software_isp/debayer_params.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2023, Red Hat Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede at redhat.com> 
+ *
+ * swstats.h - software statistics base class
+ */
+
+#pragma once
+
+namespace libcamera {
+
+struct DebayerParams {
+	/* Red Gain, 128 = 0.5, 256 = 1.0, 512 = 2.0, etc. */
+	unsigned int gainR;
+	/* Blue Gain, same range as Red Gain. */
+	unsigned int gainB;
+	/* Gamma correction, 1.0 is no correction. */
+	float gamma;
+};
+
+} /* namespace libcamera */
diff --git a/include/libcamera/internal/software_isp/meson.build b/include/libcamera/internal/software_isp/meson.build
index 1d9e4018..7e40925e 100644
--- a/include/libcamera/internal/software_isp/meson.build
+++ b/include/libcamera/internal/software_isp/meson.build
@@ -1,6 +1,8 @@
 # SPDX-License-Identifier: CC0-1.0
 
 libcamera_internal_headers += files([
+    'debayer.h',
+    'debayer_params.h',
     'swisp_stats.h',
     'swstats.h',
     'swstats_cpu.h',
diff --git a/src/libcamera/software_isp/debayer.cpp b/src/libcamera/software_isp/debayer.cpp
new file mode 100644
index 00000000..442da1ac
--- /dev/null
+++ b/src/libcamera/software_isp/debayer.cpp
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2023, Linaro Ltd
+ * Copyright (C) 2023, Red Hat Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede at redhat.com> 
+ *
+ * debayer.cpp - debayer base class
+ */
+
+#include "libcamera/internal/software_isp/debayer.h"
+
+namespace libcamera {
+
+LOG_DEFINE_CATEGORY(Debayer)
+
+Debayer::~Debayer()
+{
+}
+
+} /* namespace libcamera */
diff --git a/src/libcamera/software_isp/meson.build b/src/libcamera/software_isp/meson.build
index d31c6217..d4ae5ac7 100644
--- a/src/libcamera/software_isp/meson.build
+++ b/src/libcamera/software_isp/meson.build
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: CC0-1.0
 
 libcamera_sources += files([
+	'debayer.cpp',
 	'swstats.cpp',
 	'swstats_cpu.cpp',
 ])
-- 
2.41.0