[libcamera-devel] [PATCH v3 1/2] ipa: raspberrypi: Add sensitivity field to camera mode

[Kieran Bingham]

Hi David,

On 11/06/2021 11:07, David Plowman wrote:
> We use the CamHelper class to initialise it to the usual value of 1.
> 
> The CamHelper's GetModeSensitivity method can be redefined to
> implement a different behaviour for sensors that require it.
> 
> Signed-off-by: David Plowman <david.plowman at raspberrypi.com>

Acked-by: Kieran Bingham <kieran.bingham at ideasonboard.com>



> ---
>  src/ipa/raspberrypi/cam_helper.cpp           | 11 +++++++++++
>  src/ipa/raspberrypi/cam_helper.hpp           |  3 +++
>  src/ipa/raspberrypi/controller/camera_mode.h |  2 ++
>  src/ipa/raspberrypi/raspberrypi.cpp          |  6 ++++++
>  4 files changed, 22 insertions(+)
> 
> diff --git a/src/ipa/raspberrypi/cam_helper.cpp b/src/ipa/raspberrypi/cam_helper.cpp
> index 062e94c4..d0104da7 100644
> --- a/src/ipa/raspberrypi/cam_helper.cpp
> +++ b/src/ipa/raspberrypi/cam_helper.cpp
> @@ -130,6 +130,17 @@ bool CamHelper::SensorEmbeddedDataPresent() const
>  	return false;
>  }
>  
> +double CamHelper::GetModeSensitivity([[maybe_unused]] const CameraMode &mode) const
> +{
> +	/*
> +	 * Most sensors have the same sensitivity in every mode, but this
> +	 * method can be overridden for those that do not. Note that it is
> +	 * called before mode_ is set, so it must return the sensitivity
> +	 * of the mode that is passed in.
> +	 */
> +	return 1.0;
> +}
> +
>  unsigned int CamHelper::HideFramesStartup() const
>  {
>  	/*
> diff --git a/src/ipa/raspberrypi/cam_helper.hpp b/src/ipa/raspberrypi/cam_helper.hpp
> index f53f5c39..f524fe84 100644
> --- a/src/ipa/raspberrypi/cam_helper.hpp
> +++ b/src/ipa/raspberrypi/cam_helper.hpp
> @@ -40,6 +40,8 @@ namespace RPiController {
>  //
>  // A method to query if the sensor outputs embedded data that can be parsed.
>  //
> +// A method to return the sensitivity of a given 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
> @@ -83,6 +85,7 @@ public:
>  	virtual void GetDelays(int &exposure_delay, int &gain_delay,
>  			       int &vblank_delay) const;
>  	virtual bool SensorEmbeddedDataPresent() const;
> +	virtual double GetModeSensitivity(const CameraMode &mode) 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 2aa2335d..72c68dc6 100644
> --- a/src/ipa/raspberrypi/controller/camera_mode.h
> +++ b/src/ipa/raspberrypi/controller/camera_mode.h
> @@ -41,6 +41,8 @@ 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 1c1e802a..9ce0db08 100644
> --- a/src/ipa/raspberrypi/raspberrypi.cpp
> +++ b/src/ipa/raspberrypi/raspberrypi.cpp
> @@ -324,6 +324,12 @@ void IPARPi::setMode(const IPACameraSensorInfo &sensorInfo)
>  	 */
>  	mode_.min_frame_length = sensorInfo.minFrameLength;
>  	mode_.max_frame_length = sensorInfo.maxFrameLength;
> +
> +	/*
> +	 * Some sensors may have different sensitivities in different modes;
> +	 * the CamHelper will know the correct value.
> +	 */
> +	mode_.sensitivity = helper_->GetModeSensitivity(mode_);
>  }
>  
>  int IPARPi::configure(const IPACameraSensorInfo &sensorInfo,
> 

-- 
Regards
--
Kieran