[libcamera-devel] [PATCH v5 1/3] libcamera: Introduce camera sensor database

[Jacopo Mondi]

Introduce a 'database' of camera sensor information, which contains
the camera sensor properties which are not possible, or desirable,
to retrieve at run time.

The camera sensor database is accessed through the static SensorDatabase
class which provides a single method to obtain the sensor properties.

Reviewed-by: Hirokazu Honda <hiroh at chromium.org>
Reviewed-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 include/libcamera/internal/meson.build       |  1 +
 include/libcamera/internal/sensor_database.h | 28 ++++++
 src/libcamera/meson.build                    |  1 +
 src/libcamera/sensor_database.cpp            | 94 ++++++++++++++++++++
 4 files changed, 124 insertions(+)
 create mode 100644 include/libcamera/internal/sensor_database.h
 create mode 100644 src/libcamera/sensor_database.cpp

diff --git a/include/libcamera/internal/meson.build b/include/libcamera/internal/meson.build
index 1fe3918cfe93..4aaa76ac1db1 100644
--- a/include/libcamera/internal/meson.build
+++ b/include/libcamera/internal/meson.build
@@ -38,6 +38,7 @@ libcamera_internal_headers = files([
     'process.h',
     'pub_key.h',
     'semaphore.h',
+    'sensor_database.h',
     'sysfs.h',
     'thread.h',
     'timer.h',
diff --git a/include/libcamera/internal/sensor_database.h b/include/libcamera/internal/sensor_database.h
new file mode 100644
index 000000000000..5f58b17a7b1d
--- /dev/null
+++ b/include/libcamera/internal/sensor_database.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * sensor_database.h - Database of camera sensor properties
+ */
+#ifndef __LIBCAMERA_SENSOR_DATABASE_H__
+#define __LIBCAMERA_SENSOR_DATABASE_H__
+
+#include <string>
+
+#include <libcamera/geometry.h>
+
+namespace libcamera {
+
+struct CameraSensorProperties {
+	Size unitCellSize;
+};
+
+class SensorDatabase
+{
+public:
+	static const CameraSensorProperties *get(const std::string &sensor);
+};
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_SENSOR_DATABASE_H__ */
diff --git a/src/libcamera/meson.build b/src/libcamera/meson.build
index e0a48aa23ea5..effae0ef5186 100644
--- a/src/libcamera/meson.build
+++ b/src/libcamera/meson.build
@@ -44,6 +44,7 @@ libcamera_sources = files([
     'pub_key.cpp',
     'request.cpp',
     'semaphore.cpp',
+    'sensor_database.cpp',
     'signal.cpp',
     'stream.cpp',
     'sysfs.cpp',
diff --git a/src/libcamera/sensor_database.cpp b/src/libcamera/sensor_database.cpp
new file mode 100644
index 000000000000..d6a97e06adfc
--- /dev/null
+++ b/src/libcamera/sensor_database.cpp
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * sensor_database.cpp - Database of camera sensor properties
+ */
+
+#include "libcamera/internal/sensor_database.h"
+
+#include <map>
+
+#include "libcamera/internal/log.h"
+
+/**
+ * \file sensor_database.h
+ * \brief Database of camera sensor properties
+ *
+ * The camera sensor database collects static information about camera sensors
+ * that is not possible or desirable to retrieve at run time.
+ */
+
+namespace libcamera {
+
+LOG_DEFINE_CATEGORY(SensorDatabase)
+
+/**
+ * \struct CameraSensorProperties
+ * \brief List of sensor properties
+ *
+ * \var CameraSensorProperties::unitCellSize
+ * \brief The physical size of a pixel, including pixel edges, in nanometers.
+ */
+
+/**
+ * \class SensorDatabase
+ * \brief Access the database of camera sensor properties
+ *
+ * The database is indexed using the camera sensor model, as reported by the
+ * properties::Model property, and for each supported sensor it contains a
+ * CameraSensorProperties list of properties.
+ *
+ * The class provides a single static get() method to access the sensor database
+ * entries. If the sensor is not supported in the database nullptr is returned.
+ */
+
+namespace {
+
+/** \brief Sony IMX219 sensor properties */
+constexpr CameraSensorProperties imx219Props = {
+	.unitCellSize = { 1120, 1120 }
+};
+
+/** \brief Omnivision ov5670 sensor properties */
+constexpr CameraSensorProperties ov5670Props = {
+	.unitCellSize = { 1120, 1120 }
+};
+
+/** \brief Omnivision 13858 sensor properties */
+constexpr CameraSensorProperties ov13858Props = {
+	.unitCellSize = { 1120, 1120 }
+};
+
+#define SENSOR_PROPERTIES(_sensor) \
+	{ #_sensor, &_sensor##Props }
+
+} /* namespace */
+
+/**
+ * \brief Retrieve the properties associated with a sensor
+ * \param sensor The sensor model name
+ * \return A pointer to the CameraSensorProperties instance associated with a sensor
+ * or nullptr if the sensor is not supported in the database
+ */
+const CameraSensorProperties *SensorDatabase::get(const std::string &sensor)
+{
+	static const std::map<std::string, const CameraSensorProperties *> sensorDatabase = {
+		SENSOR_PROPERTIES(imx219),
+		SENSOR_PROPERTIES(ov5670),
+		SENSOR_PROPERTIES(ov13858),
+	};
+
+	const auto it = sensorDatabase.find(sensor);
+	if (it == sensorDatabase.end()) {
+		LOG(SensorDatabase, Warning)
+			<< "No static properties available for '" << sensor << "'";
+		LOG(SensorDatabase, Warning)
+			<< "Please consider updating the sensor database";
+		return nullptr;
+	}
+
+	return it->second;
+}
+
+} /* namespace libcamera */
-- 
2.31.1