[libcamera-devel] [PATCH 1/2] ipa: raspberrypi: Add sensitivity field to camera mode

[David Plowman]

Initialise it to the usual value of 1, until such time as we have a
mechanism that allows us to discover the correct value.

The CamHelper class also gets a method to return this sensitivity
value. This method is virtual so that it can be overridden for
specific sensors. Once the correct value is obtainable elsewhere, this
can be removed.

Signed-off-by: David Plowman <david.plowman at raspberrypi.com>
---
 src/ipa/raspberrypi/cam_helper.cpp           |  5 +++++
 src/ipa/raspberrypi/cam_helper.hpp           |  3 +++
 src/ipa/raspberrypi/controller/camera_mode.h |  2 ++
 src/ipa/raspberrypi/raspberrypi.cpp          | 12 ++++++++++++
 4 files changed, 22 insertions(+)

diff --git a/src/ipa/raspberrypi/cam_helper.cpp b/src/ipa/raspberrypi/cam_helper.cpp
index 09917f3c..71ea21ff 100644
--- a/src/ipa/raspberrypi/cam_helper.cpp
+++ b/src/ipa/raspberrypi/cam_helper.cpp
@@ -128,6 +128,11 @@ bool CamHelper::SensorEmbeddedDataPresent() const
 	return false;
 }
 
+double CamHelper::Sensitivity() const
+{
+	return mode_.sensitivity;
+}
+
 unsigned int CamHelper::HideFramesStartup() const
 {
 	/*
diff --git a/src/ipa/raspberrypi/cam_helper.hpp b/src/ipa/raspberrypi/cam_helper.hpp
index a52f3f0b..14c4714c 100644
--- a/src/ipa/raspberrypi/cam_helper.hpp
+++ b/src/ipa/raspberrypi/cam_helper.hpp
@@ -39,6 +39,8 @@ namespace RPiController {
 //
 // A method to query if the sensor outputs embedded data that can be parsed.
 //
+// A method to return the sensitivity of the current camera mode.
+//
 // A parser to parse the embedded data buffers provided by some sensors (for
 // example, the imx219 does; the ov5647 doesn't). This allows us to know for
 // sure the exposure and gain of the frame we're looking at. CamHelper
@@ -81,6 +83,7 @@ public:
 	virtual void GetDelays(int &exposure_delay, int &gain_delay,
 			       int &vblank_delay) const;
 	virtual bool SensorEmbeddedDataPresent() const;
+	virtual double Sensitivity() const;
 	virtual unsigned int HideFramesStartup() const;
 	virtual unsigned int HideFramesModeSwitch() const;
 	virtual unsigned int MistrustFramesStartup() const;
diff --git a/src/ipa/raspberrypi/controller/camera_mode.h b/src/ipa/raspberrypi/controller/camera_mode.h
index 256438c9..326f4f20 100644
--- a/src/ipa/raspberrypi/controller/camera_mode.h
+++ b/src/ipa/raspberrypi/controller/camera_mode.h
@@ -39,6 +39,8 @@ struct CameraMode {
 	libcamera::Transform transform;
 	// minimum and maximum fame lengths in units of lines
 	uint32_t min_frame_length, max_frame_length;
+	// sensitivity of this mode
+	double sensitivity;
 };
 
 #ifdef __cplusplus
diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
index e5bb8159..da42d279 100644
--- a/src/ipa/raspberrypi/raspberrypi.cpp
+++ b/src/ipa/raspberrypi/raspberrypi.cpp
@@ -321,6 +321,12 @@ void IPARPi::setMode(const IPACameraSensorInfo &sensorInfo)
 	 */
 	mode_.min_frame_length = sensorInfo.minFrameLength;
 	mode_.max_frame_length = sensorInfo.maxFrameLength;
+
+	/*
+	 * For now, initialise the mode sensitivity to the usual value of 1.
+	 * \todo Obtain the correct sensitivity number automatically.
+	 */
+	mode_.sensitivity = 1.0;
 }
 
 int IPARPi::configure(const IPACameraSensorInfo &sensorInfo,
@@ -379,6 +385,12 @@ int IPARPi::configure(const IPACameraSensorInfo &sensorInfo,
 	/* Pass the camera mode to the CamHelper to setup algorithms. */
 	helper_->SetCameraMode(mode_);
 
+	/*
+	 * For now, the CamHelper knows the sensitivity correctly.
+	 * \todo This can be removed once the sensitivity is initialised properly.
+	 */
+	mode_.sensitivity = helper_->Sensitivity();
+
 	if (firstStart_) {
 		/* Supply initial values for frame durations. */
 		applyFrameDurations(defaultMinFrameDuration, defaultMaxFrameDuration);
-- 
2.20.1