[libcamera-devel] [PATCH v3 07/13] libcamera: camera_sensor: Define CameraSensorInfo

[Jacopo Mondi]

Define the CameraSensorInfo structure that reports the current image sensor
configuration.

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/libcamera/camera_sensor.cpp       | 99 +++++++++++++++++++++++++++
 src/libcamera/include/camera_sensor.h | 13 ++++
 2 files changed, 112 insertions(+)

diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
index a54751fecf5a..e39f277622ae 100644
--- a/src/libcamera/camera_sensor.cpp
+++ b/src/libcamera/camera_sensor.cpp
@@ -28,6 +28,105 @@ namespace libcamera {
 
 LOG_DEFINE_CATEGORY(CameraSensor);
 
+/**
+ * \struct CameraSensorInfo
+ * \brief Report the image sensor characteristics
+ *
+ * The structure reports image sensor characteristics used by IPA modules to
+ * tune their algorithms based on the image sensor model currently in use and
+ * its configuration.
+ *
+ * The here reported information describe the sensor's intrinsics
+ * characteristics, such as its pixel array size and the sensor model name,
+ * as well as information relative to the currently configured mode, such as
+ * the produced image size and the bit depth of the requested image format.
+ *
+ * Instances of this structure are meant to be assembled by the CameraSensor
+ * class and its specialized subclasses by inspecting the sensor static
+ * properties as well as the currently configured sensor mode.
+ */
+
+/**
+ * \var CameraSensorInfo::name
+ * \brief The image sensor name
+ */
+
+/**
+ * \var CameraSensorInfo::bitsPerPixel
+ * \brief The bits per-pixel of the image format produced by the image sensor
+ */
+
+/**
+ * \var CameraSensorInfo::activeAreaSize
+ * \brief The size of the active pixel array area of the sensor
+ * \sa properties::PixelArray
+ */
+
+/**
+ * \var CameraSensorInfo::analogCrop
+ * \brief The portion of the pixel array active area which is read-out and
+ * processed
+ *
+ * The analog crop rectangle top-left corner is defined as the displacement
+ * from the top-left corner of the pixel array active area. The rectangle
+ * horizontal and vertical sizes define the portion of the pixel matrix which
+ * is read-out and provided to the sensor's on-board processing pipeline, before
+ * any pixel sub-sampling method, such as pixel binning, skipping and averaging
+ * take place.
+ */
+
+/**
+ * \var CameraSensorInfo::outputSize
+ * \brief The size of the images produced by the camera sensor
+ *
+ * The output image size defines the horizontal and vertical sizes of the images
+ * produced by the image sensor. The final output image size is defined as the
+ * end result of the sensor's on-board image processing pipeline stages, applied
+ * on the pixel array portion defined by the analog crop rectangle. Each image
+ * processing stage that performs pixel sub-sampling techniques, such as pixel
+ * binning or skipping, or perform any additional digital scaling concur in
+ * the definition of the final output image size.
+ */
+
+/**
+ * \var CameraSensorInfo::lineLength
+ * \brief Total line length in pixels
+ *
+ * The total line length in pixels, including blanking and synchronism signal
+ * active state duration.
+ *
+ * In example:
+ *
+ * \verbatim
+                _______     _______     ___
+  HREF  ... ___|       |___|       |___|     ...
+              _           _           _
+  HSYNC ... _| |_________| |_________| |__   ...
+
+  Valid ... ....xxxxxxxx....xxxxxxxx....xxx  ...
+  Data
+
+  Line	  ... /-----------/-----------/---  ...
+  Length
+
+  \endverbatim
+ */
+
+/**
+ * \var CameraSensorInfo::pixelClock
+ * \brief The pixel clock in Hz
+ *
+ * The pixel read out frequency in Hz. The property describes how many pixel
+ * per second are produced by the camera sensor, including blankings and
+ * synchronism signal active state duration.
+ *
+ * To obtain the read-out time in second of a full line:
+ *
+ * \verbatim
+	LineDuration(s) = lineLength(pixel) / pixelClock(Hz)
+   \endverbatim
+ */
+
 /**
  * \class CameraSensor
  * \brief A camera sensor based on V4L2 subdevices
diff --git a/src/libcamera/include/camera_sensor.h b/src/libcamera/include/camera_sensor.h
index 8fa4d450f959..e19852d4cabe 100644
--- a/src/libcamera/include/camera_sensor.h
+++ b/src/libcamera/include/camera_sensor.h
@@ -22,6 +22,19 @@ class V4L2Subdevice;
 
 struct V4L2SubdeviceFormat;
 
+struct CameraSensorInfo {
+	std::string name;
+
+	uint32_t bitsPerPixel;
+
+	Size activeAreaSize;
+	Rectangle analogCrop;
+	Size outputSize;
+
+	uint32_t pixelClock;
+	uint32_t lineLength;
+};
+
 class CameraSensor : protected Loggable
 {
 public:
-- 
2.26.1