[PATCH v2 9/9] ipa: rkisp1: agc: Implement ExposureValue control

[Kieran Bingham]

Quoting Stefan Klug (2025-04-11 13:36:37)
> Now that agc_mean_luminance supports exposure correction, implement the
> corresponding ExposureValue control for rkisp1.

Definitely looking forward to the control initialisation and handling of
context/state somehow being managed by the agc_mean_luminence algorithm
directly sometime so that all of the users of agc_mean_luminence also
can support this control.

Should we already add this to IPU3 and Mali-C55 explicitly?

> 
> Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>

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

> ---
>  src/ipa/rkisp1/algorithms/agc.cpp | 10 ++++++++++
>  src/ipa/rkisp1/ipa_context.h      |  2 ++
>  2 files changed, 12 insertions(+)
> 
> diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp
> index b3ac9400b74f..8e77455e7afd 100644
> --- a/src/ipa/rkisp1/algorithms/agc.cpp
> +++ b/src/ipa/rkisp1/algorithms/agc.cpp
> @@ -158,6 +158,7 @@ int Agc::init(IPAContext &context, const YamlObject &tuningData)
>                             ControlValue(controls::AnalogueGainModeAuto));
>         /* \todo Move this to the Camera class */
>         context.ctrlMap[&controls::AeEnable] = ControlInfo(false, true, true);
> +       context.ctrlMap[&controls::ExposureValue] = ControlInfo(-8.0f, 8.0f, 0.0f);
>         context.ctrlMap.merge(controls());
>  
>         return 0;
> @@ -180,6 +181,7 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo)
>         context.activeState.agc.manual.exposure = context.activeState.agc.automatic.exposure;
>         context.activeState.agc.autoExposureEnabled = !context.configuration.raw;
>         context.activeState.agc.autoGainEnabled = !context.configuration.raw;
> +       context.activeState.agc.exposureValue = 0.0;
>  
>         context.activeState.agc.constraintMode =
>                 static_cast<controls::AeConstraintModeEnum>(constraintModes().begin()->first);
> @@ -302,6 +304,11 @@ void Agc::queueRequest(IPAContext &context,
>                         static_cast<controls::AeConstraintModeEnum>(*constraintMode);
>         frameContext.agc.constraintMode = agc.constraintMode;
>  
> +       const auto &exposureValue = controls.get(controls::ExposureValue);
> +       if (exposureValue)
> +               agc.exposureValue = *exposureValue;
> +       frameContext.agc.exposureValue = agc.exposureValue;
> +
>         const auto &frameDurationLimits = controls.get(controls::FrameDurationLimits);
>         if (frameDurationLimits) {
>                 /* Limit the control value to the limits in ControlInfo */
> @@ -408,6 +415,7 @@ void Agc::fillMetadata(IPAContext &context, IPAFrameContext &frameContext,
>         metadata.set(controls::AeMeteringMode, frameContext.agc.meteringMode);
>         metadata.set(controls::AeExposureMode, frameContext.agc.exposureMode);
>         metadata.set(controls::AeConstraintMode, frameContext.agc.constraintMode);
> +       metadata.set(controls::ExposureValue, frameContext.agc.exposureValue);
>  }
>  
>  /**
> @@ -557,6 +565,8 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
>         double analogueGain = frameContext.sensor.gain;
>         utils::Duration effectiveExposureValue = exposureTime * analogueGain;
>  
> +       setExposureCompensation(pow(2.0, frameContext.agc.exposureValue));
> +
>         utils::Duration newExposureTime;
>         double aGain, dGain;
>         std::tie(newExposureTime, aGain, dGain) =
> diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h
> index f0d504215d34..7ccc7b501aff 100644
> --- a/src/ipa/rkisp1/ipa_context.h
> +++ b/src/ipa/rkisp1/ipa_context.h
> @@ -81,6 +81,7 @@ struct IPAActiveState {
>  
>                 bool autoExposureEnabled;
>                 bool autoGainEnabled;
> +               double exposureValue;
>                 controls::AeConstraintModeEnum constraintMode;
>                 controls::AeExposureModeEnum exposureMode;
>                 controls::AeMeteringModeEnum meteringMode;
> @@ -129,6 +130,7 @@ struct IPAFrameContext : public FrameContext {
>         struct {
>                 uint32_t exposure;
>                 double gain;
> +               double exposureValue;
>                 uint32_t vblank;
>                 bool autoExposureEnabled;
>                 bool autoGainEnabled;
> -- 
> 2.43.0
>