[libcamera-devel] [PATCH v4 1/3] libcamera: Introduce camera sensor database

[Jacopo Mondi]

Introduce a 'database' of camera sensor information, which contains
a the camera sensor properties which is 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 information.

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            | 97 ++++++++++++++++++++
 4 files changed, 127 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..7d743e46102d
--- /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 SensorInfo {
+	Size unitCellSize;
+};
+
+class SensorDatabase
+{
+public:
+	static const SensorInfo *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..68e69e8bf1b6
--- /dev/null
+++ b/src/libcamera/sensor_database.cpp
@@ -0,0 +1,97 @@
+/* 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 <algorithm>
+
+namespace libcamera {
+
+/**
+ * \file sensor_database.h
+ * \brief Database of camera sensor properties
+ *
+ * The camera sensor database collects information on camera sensors
+ * which is not possible or desirable to retrieve at run-time.
+ */
+
+/**
+ * \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
+ * SensorInfo list of properties.
+ *
+ * The class provides a single static getInfo() method to access the sensor
+ * database entries. If the sensor is not supported in the database nullptr is
+ * returned.
+ */
+
+/**
+ * \struct SensorInfo
+ * \brief List of sensor properties
+ *
+ * \var SensorInfo::unitCellSize
+ * \brief The physical size of pixel, including pixel edges. Width x height in
+ * nano-meters.
+ */
+
+namespace {
+
+/**
+ * \brief Sony IMX219 sensor properties
+ */
+constexpr SensorInfo imx219Info = {
+	.unitCellSize = { 1120, 1120 }
+};
+
+/**
+ * \brief Omnivision ov5670 sensor properties
+ */
+constexpr SensorInfo ov5670Info = {
+	.unitCellSize = { 1120, 1120 }
+};
+
+/**
+ * \brief Omnivision 13858 sensor properties
+ */
+constexpr SensorInfo ov13858Info = {
+	.unitCellSize = { 1120, 1120 }
+};
+
+#define SENSOR_INFO(_sensor) \
+	{ #_sensor, &_sensor##Info }
+
+/*
+ * \brief The database of sensor properties
+ */
+constexpr std::pair<const char *const, const SensorInfo *> sensorDatabase__[] = {
+	SENSOR_INFO(imx219),
+	SENSOR_INFO(ov5670),
+	SENSOR_INFO(ov13858),
+};
+
+} /* namespace */
+
+/**
+ * \brief Retrieve the properties associated with a sensor
+ * \param sensor The sensor model name
+ * \return A pointer to the SensorInfo instance associated with a sensor or
+ * nullptr if the sensor is not supported in the database
+ */
+const SensorInfo *SensorDatabase::get(const std::string &sensor)
+{
+	for (unsigned int i = 0; i < std::size(sensorDatabase__); ++i) {
+		if (sensorDatabase__[i].first == sensor)
+			return sensorDatabase__[i].second;
+	}
+
+	return nullptr;
+}
+
+} /* namespace libcamera */
-- 
2.31.1