[PATCH v2 3/3] rkisp1: Honor the FrameDurationLimits control

Kieran Bingham kieran.bingham at ideasonboard.com
Sat Feb 22 15:09:01 CET 2025


Quoting Paul Elder (2025-02-21 09:20:45)
> Add support to rkisp1 for controlling the framerate via the
> FrameDurationLimits control.
> 
> Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
> Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> Reviewed-by: Umang Jain <umang.jain at ideasonboard.com>
> 
> ---
> Changes in v2:
> - recover from bitrot
> - fix setting frame duration limits in raw mode
> ---
>  src/ipa/rkisp1/algorithms/agc.cpp        | 60 +++++++++++++++++++-----
>  src/ipa/rkisp1/algorithms/agc.h          |  3 ++
>  src/ipa/rkisp1/ipa_context.cpp           | 16 ++++++-
>  src/ipa/rkisp1/ipa_context.h             |  4 ++
>  src/ipa/rkisp1/rkisp1.cpp                |  2 +
>  src/libcamera/pipeline/rkisp1/rkisp1.cpp |  1 +
>  6 files changed, 74 insertions(+), 12 deletions(-)
> 
> diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp
> index 5fece545677e..4e0e3734117e 100644
> --- a/src/ipa/rkisp1/algorithms/agc.cpp
> +++ b/src/ipa/rkisp1/algorithms/agc.cpp
> @@ -190,6 +190,7 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo)
>  
>         /* Limit the frame duration to match current initialisation */
>         ControlInfo &frameDurationLimits = context.ctrlMap[&controls::FrameDurationLimits];
> +       context.activeState.agc.minFrameDuration = std::chrono::microseconds(frameDurationLimits.min().get<int64_t>());
>         context.activeState.agc.maxFrameDuration = std::chrono::microseconds(frameDurationLimits.max().get<int64_t>());
>  
>         /*
> @@ -307,10 +308,21 @@ void Agc::queueRequest(IPAContext &context,
>  
>         const auto &frameDurationLimits = controls.get(controls::FrameDurationLimits);
>         if (frameDurationLimits) {
> -               utils::Duration maxFrameDuration =
> -                       std::chrono::milliseconds((*frameDurationLimits).back());
> -               agc.maxFrameDuration = maxFrameDuration;
> +               /* Limit the control value to the limits in ControlInfo */
> +               ControlInfo &limits = context.ctrlMap[&controls::FrameDurationLimits];
> +               int64_t minFrameDuration =
> +                       std::clamp((*frameDurationLimits).front(),
> +                                  limits.min().get<int64_t>(),
> +                                  limits.max().get<int64_t>());
> +               int64_t maxFrameDuration =
> +                       std::clamp((*frameDurationLimits).back(),
> +                                  limits.min().get<int64_t>(),
> +                                  limits.max().get<int64_t>());
> +
> +               agc.minFrameDuration = std::chrono::microseconds(minFrameDuration);
> +               agc.maxFrameDuration = std::chrono::microseconds(maxFrameDuration);
>         }
> +       frameContext.agc.minFrameDuration = agc.minFrameDuration;
>         frameContext.agc.maxFrameDuration = agc.maxFrameDuration;
>  }
>  
> @@ -387,6 +399,7 @@ void Agc::fillMetadata(IPAContext &context, IPAFrameContext &frameContext,
>                                      * frameContext.sensor.exposure;
>         metadata.set(controls::AnalogueGain, frameContext.sensor.gain);
>         metadata.set(controls::ExposureTime, exposureTime.get<std::micro>());
> +       metadata.set(controls::FrameDuration, frameContext.agc.frameDuration.get<std::micro>());
>         metadata.set(controls::ExposureTimeMode,
>                      frameContext.agc.autoExposureEnabled
>                      ? controls::ExposureTimeModeAuto
> @@ -396,13 +409,6 @@ void Agc::fillMetadata(IPAContext &context, IPAFrameContext &frameContext,
>                      ? controls::AnalogueGainModeAuto
>                      : controls::AnalogueGainModeManual);
>  
> -       /* \todo Use VBlank value calculated from each frame exposure. */
> -       uint32_t vTotal = context.configuration.sensor.size.height
> -                       + context.configuration.sensor.defVBlank;
> -       utils::Duration frameDuration = context.configuration.sensor.lineDuration
> -                                     * vTotal;
> -       metadata.set(controls::FrameDuration, frameDuration.get<std::micro>());

Am I missing where the FrameDuration is now reported in the metadata ?
or has it been removed completely.

I think we should still be reporting the FrameDuration which has been
determined. It should come from
  frameContext.agc.frameDuration.get<std::micro>()

now shouldn't it ?



> -
>         metadata.set(controls::AeMeteringMode, frameContext.agc.meteringMode);
>         metadata.set(controls::AeExposureMode, frameContext.agc.exposureMode);
>         metadata.set(controls::AeConstraintMode, frameContext.agc.constraintMode);
> @@ -444,6 +450,27 @@ double Agc::estimateLuminance(double gain) const
>         return ySum / expMeans_.size() / 255;
>  }
>  
> +/**
> + * \brief Process frame duration and compute vblank
> + * \param[in] context The shared IPA context
> + * \param[in] frameContext The current frame context
> + * \param[in] frameDuration The target frame duration
> + *
> + * Compute and populate vblank from the target frame duration.
> + */
> +void Agc::processFrameDuration(IPAContext &context,
> +                              IPAFrameContext &frameContext,
> +                              utils::Duration frameDuration)
> +{
> +       IPACameraSensorInfo &sensorInfo = context.sensorInfo;
> +       utils::Duration lineDuration = context.configuration.sensor.lineDuration;
> +
> +       frameContext.agc.vblank = (frameDuration / lineDuration) - sensorInfo.outputSize.height;
> +
> +       /* Update frame duration accounting for line length quantization. */
> +       frameContext.agc.frameDuration = (sensorInfo.outputSize.height + frameContext.agc.vblank) * lineDuration;
> +}
> +
>  /**
>   * \brief Process RkISP1 statistics, and run AGC operations
>   * \param[in] context The shared IPA context
> @@ -460,6 +487,8 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
>                   ControlList &metadata)
>  {
>         if (!stats) {
> +               processFrameDuration(context, frameContext,
> +                                    frameContext.agc.minFrameDuration);
>                 fillMetadata(context, frameContext, metadata);
>                 return;
>         }
> @@ -497,7 +526,9 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
>         double maxAnalogueGain;
>  
>         if (frameContext.agc.autoExposureEnabled) {
> -               minExposureTime = context.configuration.sensor.minExposureTime;
> +               minExposureTime = std::clamp(frameContext.agc.minFrameDuration,
> +                                            context.configuration.sensor.minExposureTime,
> +                                            context.configuration.sensor.maxExposureTime);
>                 maxExposureTime = std::clamp(frameContext.agc.maxFrameDuration,
>                                              context.configuration.sensor.minExposureTime,
>                                              context.configuration.sensor.maxExposureTime);
> @@ -541,6 +572,13 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
>         activeState.agc.automatic.exposure = newExposureTime / lineDuration;
>         activeState.agc.automatic.gain = aGain;
>  
> +       /*
> +        * Expand the target frame duration so that we do not run faster than
> +        * the minimum frame duration when we have short exposures.
> +        */
> +       processFrameDuration(context, frameContext,
> +                            std::max(frameContext.agc.minFrameDuration, newExposureTime));
> +
>         fillMetadata(context, frameContext, metadata);
>         expMeans_ = {};
>  }
> diff --git a/src/ipa/rkisp1/algorithms/agc.h b/src/ipa/rkisp1/algorithms/agc.h
> index aa86f2c5bc21..62bcde999fe3 100644
> --- a/src/ipa/rkisp1/algorithms/agc.h
> +++ b/src/ipa/rkisp1/algorithms/agc.h
> @@ -50,6 +50,9 @@ private:
>         void fillMetadata(IPAContext &context, IPAFrameContext &frameContext,
>                           ControlList &metadata);
>         double estimateLuminance(double gain) const override;
> +       void processFrameDuration(IPAContext &context,
> +                                 IPAFrameContext &frameContext,
> +                                 utils::Duration frameDuration);
>  
>         Span<const uint8_t> expMeans_;
>  
> diff --git a/src/ipa/rkisp1/ipa_context.cpp b/src/ipa/rkisp1/ipa_context.cpp
> index 261c0472a4fc..99611bd5b390 100644
> --- a/src/ipa/rkisp1/ipa_context.cpp
> +++ b/src/ipa/rkisp1/ipa_context.cpp
> @@ -180,6 +180,9 @@ namespace libcamera::ipa::rkisp1 {
>   * \var IPAActiveState::agc.meteringMode
>   * \brief Metering mode as set by the AeMeteringMode control
>   *
> + * \var IPAActiveState::agc.minFrameDuration
> + * \brief Minimum frame duration as set by the FrameDurationLimits control
> + *
>   * \var IPAActiveState::agc.maxFrameDuration
>   * \brief Maximum frame duration as set by the FrameDurationLimits control
>   */
> @@ -282,7 +285,9 @@ namespace libcamera::ipa::rkisp1 {
>   * \brief Automatic Gain Control parameters for this frame
>   *
>   * The exposure and gain are provided by the AGC algorithm, and are to be
> - * applied to the sensor in order to take effect for this frame.
> + * applied to the sensor in order to take effect for this frame. Additionally
> + * the vertical blanking period is determined to maintain a consistent frame
> + * rate matched to the FrameDurationLimits as set by the user.
>   *
>   * \var IPAFrameContext::agc.exposure
>   * \brief Exposure time expressed as a number of lines computed by the algorithm
> @@ -292,6 +297,9 @@ namespace libcamera::ipa::rkisp1 {
>   *
>   * The gain should be adapted to the sensor specific gain code before applying.
>   *
> + * \var IPAFrameContext::agc.vblank
> + * \brief Vertical blanking parameter computed by the algorithm
> + *
>   * \var IPAFrameContext::agc.autoExposureEnabled
>   * \brief Manual/automatic AGC state (exposure) as set by the ExposureTimeMode control
>   *
> @@ -307,9 +315,15 @@ namespace libcamera::ipa::rkisp1 {
>   * \var IPAFrameContext::agc.meteringMode
>   * \brief Metering mode as set by the AeMeteringMode control
>   *
> + * \var IPAFrameContext::agc.minFrameDuration
> + * \brief Minimum frame duration as set by the FrameDurationLimits control
> + *
>   * \var IPAFrameContext::agc.maxFrameDuration
>   * \brief Maximum frame duration as set by the FrameDurationLimits control
>   *
> + * \var IPAFrameContext::agc.frameDuration
> + * \brief The actual FrameDuration used by the algorithm for the frame
> + *
>   * \var IPAFrameContext::agc.updateMetering
>   * \brief Indicate if new ISP AGC metering parameters need to be applied
>   *
> diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h
> index c765b928a55f..474f7036f003 100644
> --- a/src/ipa/rkisp1/ipa_context.h
> +++ b/src/ipa/rkisp1/ipa_context.h
> @@ -84,6 +84,7 @@ struct IPAActiveState {
>                 controls::AeConstraintModeEnum constraintMode;
>                 controls::AeExposureModeEnum exposureMode;
>                 controls::AeMeteringModeEnum meteringMode;
> +               utils::Duration minFrameDuration;
>                 utils::Duration maxFrameDuration;
>         } agc;
>  
> @@ -125,12 +126,15 @@ struct IPAFrameContext : public FrameContext {
>         struct {
>                 uint32_t exposure;
>                 double gain;
> +               uint32_t vblank;
>                 bool autoExposureEnabled;
>                 bool autoGainEnabled;
>                 controls::AeConstraintModeEnum constraintMode;
>                 controls::AeExposureModeEnum exposureMode;
>                 controls::AeMeteringModeEnum meteringMode;
> +               utils::Duration minFrameDuration;
>                 utils::Duration maxFrameDuration;
> +               utils::Duration frameDuration;
>                 bool updateMetering;
>                 bool autoExposureModeChange;
>                 bool autoGainModeChange;
> diff --git a/src/ipa/rkisp1/rkisp1.cpp b/src/ipa/rkisp1/rkisp1.cpp
> index 0e761249d27c..7547d2f274f4 100644
> --- a/src/ipa/rkisp1/rkisp1.cpp
> +++ b/src/ipa/rkisp1/rkisp1.cpp
> @@ -453,10 +453,12 @@ void IPARkISP1::setControls(unsigned int frame)
>         IPAFrameContext &frameContext = context_.frameContexts.get(frame);
>         uint32_t exposure = frameContext.agc.exposure;
>         uint32_t gain = context_.camHelper->gainCode(frameContext.agc.gain);
> +       uint32_t vblank = frameContext.agc.vblank;
>  
>         ControlList ctrls(sensorControls_);
>         ctrls.set(V4L2_CID_EXPOSURE, static_cast<int32_t>(exposure));
>         ctrls.set(V4L2_CID_ANALOGUE_GAIN, static_cast<int32_t>(gain));
> +       ctrls.set(V4L2_CID_VBLANK, static_cast<int32_t>(vblank));
>  
>         setSensorControls.emit(frame, ctrls);
>  }
> diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
> index 1ac8d8ae7ed9..52633fe3cb85 100644
> --- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
> +++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
> @@ -1325,6 +1325,7 @@ int PipelineHandlerRkISP1::createCamera(MediaEntity *sensor)
>         std::unordered_map<uint32_t, DelayedControls::ControlParams> params = {
>                 { V4L2_CID_ANALOGUE_GAIN, { delays.gainDelay, false } },
>                 { V4L2_CID_EXPOSURE, { delays.exposureDelay, false } },
> +               { V4L2_CID_VBLANK, { 1, false } },
>         };
>  
>         data->delayedCtrls_ =
> -- 
> 2.39.2
>


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