[libcamera-devel,1/2] libcamera: camera: add a mode sensitivity field
diff mbox series

Message ID 20210628085630.2081-2-david.plowman@raspberrypi.com
State Superseded
Headers show
Series
  • Application support for per-mode sensitivities
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Commit Message

David Plowman June 28, 2021, 8:56 a.m. UTC
The modeSensitivity field is a number that describes how sensitive the
selected sensor mode is compared to other readout modes of the same
sensor. For example, a binned mode might have twice the sensitivity of
the full resolution mode, meaning you would get double the signal
level for the same exposure and gains.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
---
 include/libcamera/camera.h |  2 ++
 src/libcamera/camera.cpp   | 16 +++++++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

Patch
diff mbox series

diff --git a/include/libcamera/camera.h b/include/libcamera/camera.h
index d7164180..85f7f999 100644
--- a/include/libcamera/camera.h
+++ b/include/libcamera/camera.h
@@ -65,6 +65,8 @@  public:
 
 	Transform transform;
 
+	float modeSensitivity;
+
 protected:
 	CameraConfiguration();
 
diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index 1340c266..6b3627b6 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -154,7 +154,7 @@  LOG_DECLARE_CATEGORY(Camera)
  * \brief Create an empty camera configuration
  */
 CameraConfiguration::CameraConfiguration()
-	: transform(Transform::Identity), config_({})
+	: transform(Transform::Identity), modeSensitivity(1.0), config_({})
 {
 }
 
@@ -325,6 +325,20 @@  std::size_t CameraConfiguration::size() const
  * may adjust this field at its discretion if the selection is not supported.
  */
 
+/**
+ * \var CameraConfiguration::modeSensitivity
+ * \brief The relative sensitivity of the chosen sensor mode
+ *
+ * Some sensors have readout modes with different sensitivities. For example,
+ * a binned camera mode might, with the same exposure and gains, produce
+ * twice the signal level of the full resolution readout. This would be
+ * signalled by the binned mode, when it is chosen, indicating a value here
+ * that is twice that of the full resolution mode.
+ *
+ * This value should only be read, and not set, by the user. It will be
+ * valid after the configure method has reteurned successfully.
+ */
+
 /**
  * \var CameraConfiguration::config_
  * \brief The vector of stream configurations