[PATCH 2/3] ipa: rkisp1: Refer to integration time rather than shutter speed
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Wed May 8 15:34:00 CEST 2024
Hi Dan,
Thank you for the patch.
On Thu, Apr 18, 2024 at 01:46:31PM +0100, Daniel Scally wrote:
> Multiple variables referencing shutter speed in the RkISP1 IPA module
> are in fact calculated and used as integration time. The discrepancy
> is problematic given the minimum shutter speed would produce the max
> integration time.
>
> Replace references to shutter speed with integration time.
>
> Signed-off-by: Daniel Scally <dan.scally at ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> ---
> src/ipa/rkisp1/algorithms/agc.cpp | 4 ++--
> src/ipa/rkisp1/ipa_context.cpp | 8 ++++----
> src/ipa/rkisp1/ipa_context.h | 4 ++--
> src/ipa/rkisp1/rkisp1.cpp | 8 ++++----
> 4 files changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp
> index 27b6f2c1..13f54398 100644
> --- a/src/ipa/rkisp1/algorithms/agc.cpp
> +++ b/src/ipa/rkisp1/algorithms/agc.cpp
> @@ -95,8 +95,8 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo)
> context.configuration.agc.measureWindow.v_size = 3 * configInfo.outputSize.height / 4;
>
> /* \todo Run this again when FrameDurationLimits is passed in */
> - configureExposureModeHelpers(context.configuration.sensor.minShutterSpeed,
> - context.configuration.sensor.maxShutterSpeed,
> + configureExposureModeHelpers(context.configuration.sensor.minIntegrationTime,
> + context.configuration.sensor.maxIntegrationTime,
> context.configuration.sensor.minAnalogueGain,
> context.configuration.sensor.maxAnalogueGain);
>
> diff --git a/src/ipa/rkisp1/ipa_context.cpp b/src/ipa/rkisp1/ipa_context.cpp
> index 070834fa..991ca1c2 100644
> --- a/src/ipa/rkisp1/ipa_context.cpp
> +++ b/src/ipa/rkisp1/ipa_context.cpp
> @@ -78,11 +78,11 @@ namespace libcamera::ipa::rkisp1 {
> * \var IPASessionConfiguration::sensor
> * \brief Sensor-specific configuration of the IPA
> *
> - * \var IPASessionConfiguration::sensor.minShutterSpeed
> - * \brief Minimum shutter speed supported with the sensor
> + * \var IPASessionConfiguration::sensor.minIntegrationTime
> + * \brief Minimum integration time supported with the sensor
> *
> - * \var IPASessionConfiguration::sensor.maxShutterSpeed
> - * \brief Maximum shutter speed supported with the sensor
> + * \var IPASessionConfiguration::sensor.maxIntegrationTime
> + * \brief Maximum integration time supported with the sensor
> *
> * \var IPASessionConfiguration::sensor.minAnalogueGain
> * \brief Minimum analogue gain supported with the sensor
> diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h
> index 256b75eb..3405a260 100644
> --- a/src/ipa/rkisp1/ipa_context.h
> +++ b/src/ipa/rkisp1/ipa_context.h
> @@ -43,8 +43,8 @@ struct IPASessionConfiguration {
> } lsc;
>
> struct {
> - utils::Duration minShutterSpeed;
> - utils::Duration maxShutterSpeed;
> + utils::Duration minIntegrationTime;
> + utils::Duration maxIntegrationTime;
> double minAnalogueGain;
> double maxAnalogueGain;
>
> diff --git a/src/ipa/rkisp1/rkisp1.cpp b/src/ipa/rkisp1/rkisp1.cpp
> index d8610095..15919d3f 100644
> --- a/src/ipa/rkisp1/rkisp1.cpp
> +++ b/src/ipa/rkisp1/rkisp1.cpp
> @@ -245,14 +245,14 @@ int IPARkISP1::configure(const IPAConfigInfo &ipaConfig,
>
> /*
> * When the AGC computes the new exposure values for a frame, it needs
> - * to know the limits for shutter speed and analogue gain.
> + * to know the limits for integration time and analogue gain.
> * As it depends on the sensor, update it with the controls.
> *
> - * \todo take VBLANK into account for maximum shutter speed
> + * \todo take VBLANK into account for maximum integration time
> */
> - context_.configuration.sensor.minShutterSpeed =
> + context_.configuration.sensor.minIntegrationTime =
> minExposure * context_.configuration.sensor.lineDuration;
> - context_.configuration.sensor.maxShutterSpeed =
> + context_.configuration.sensor.maxIntegrationTime =
> maxExposure * context_.configuration.sensor.lineDuration;
> context_.configuration.sensor.minAnalogueGain = camHelper_->gain(minGain);
> context_.configuration.sensor.maxAnalogueGain = camHelper_->gain(maxGain);
--
Regards,
Laurent Pinchart
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