[PATCH v2 10/17] ipa: rkisp1: ccm/lsc: Fix CCM/LSC based on manual color temperature

Stefan Klug stefan.klug at ideasonboard.com
Tue Apr 1 23:41:43 CEST 2025


On Mon, Mar 31, 2025 at 06:30:41PM +0100, Kieran Bingham wrote:
> Quoting Stefan Klug (2025-03-19 16:11:15)
> > In RkISP1Awb::process(), the color temperature in the active state is
> > updated every time new statistics are available.  The CCM/LSC algorithms
> > use that value in prepare() to update the CCM/LSC. This is not correct
> > if the color temperature was specified manually and leads to visible
> > flicker even when AwbEnable is set to false.
> > 
> > To fix that, track the auto and manual color temperature separately in
> > active state. In Awb::prepare() the current frame context is updated
> > with the corresponding value from active state. Change the algorithms to
> > fetch the color temperature from the frame context instead of the active
> > state in prepare().
> > 
> > Fixes: 02308809548d ("ipa: rkisp1: awb: Implement ColourTemperature control")
> > Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>
> > 
> > ---
> > 
> > Changes in v2:
> > - None
> > ---
> >  src/ipa/rkisp1/algorithms/awb.cpp | 18 ++++++++++--------
> >  src/ipa/rkisp1/algorithms/ccm.cpp |  2 +-
> >  src/ipa/rkisp1/algorithms/lsc.cpp |  6 +++---
> >  src/ipa/rkisp1/ipa_context.h      |  2 +-
> >  4 files changed, 15 insertions(+), 13 deletions(-)
> > 
> > diff --git a/src/ipa/rkisp1/algorithms/awb.cpp b/src/ipa/rkisp1/algorithms/awb.cpp
> > index a9759e53f593..5e067e50cd52 100644
> > --- a/src/ipa/rkisp1/algorithms/awb.cpp
> > +++ b/src/ipa/rkisp1/algorithms/awb.cpp
> > @@ -128,7 +128,8 @@ int Awb::configure(IPAContext &context,
> >         context.activeState.awb.automatic.gains =
> >                 awbAlgo_->gainsFromColourTemperature(kDefaultColourTemperature);
> >         context.activeState.awb.autoEnabled = true;
> > -       context.activeState.awb.temperatureK = kDefaultColourTemperature;
> > +       context.activeState.awb.manual.temperatureK = kDefaultColourTemperature;
> > +       context.activeState.awb.automatic.temperatureK = kDefaultColourTemperature;
> >  
> >         /*
> >          * Define the measurement window for AWB as a centered rectangle
> > @@ -185,7 +186,7 @@ void Awb::queueRequest(IPAContext &context,
> >                 const auto &gains = awbAlgo_->gainsFromColourTemperature(*colourTemperature);
> >                 awb.manual.gains.r() = gains.r();
> >                 awb.manual.gains.b() = gains.b();
> > -               awb.temperatureK = *colourTemperature;
> > +               awb.manual.temperatureK = *colourTemperature;
> >                 update = true;
> >         }
> >  
> > @@ -194,7 +195,7 @@ void Awb::queueRequest(IPAContext &context,
> >                         << "Set colour gains to " << awb.manual.gains;
> >  
> >         frameContext.awb.gains = awb.manual.gains;
> > -       frameContext.awb.temperatureK = awb.temperatureK;
> > +       frameContext.awb.temperatureK = awb.manual.temperatureK;
> >  }
> >  
> >  /**
> > @@ -208,8 +209,9 @@ void Awb::prepare(IPAContext &context, const uint32_t frame,
> >          * most up-to-date automatic values we can read.
> >          */
> >         if (frameContext.awb.autoEnabled) {
> > -               frameContext.awb.gains = context.activeState.awb.automatic.gains;
> > -               frameContext.awb.temperatureK = context.activeState.awb.temperatureK;
> > +               auto &awb = context.activeState.awb;
> > +               frameContext.awb.gains = awb.automatic.gains;
> > +               frameContext.awb.temperatureK = awb.automatic.temperatureK;
> >         }
> >  
> >         auto gainConfig = params->block<BlockType::AwbGain>();
> > @@ -309,10 +311,10 @@ void Awb::process(IPAContext &context,
> >         RkISP1AwbStats awbStats{ rgbMeans };
> >         AwbResult awbResult = awbAlgo_->calculateAwb(awbStats, frameContext.lux.lux);
> >  
> > -       activeState.awb.temperatureK = awbResult.colourTemperature;
> > +       activeState.awb.automatic.temperatureK = awbResult.colourTemperature;
> >  
> >         /* Metadata shall contain the up to date measurement */
> > -       metadata.set(controls::ColourTemperature, activeState.awb.temperatureK);
> > +       metadata.set(controls::ColourTemperature, activeState.awb.automatic.temperatureK);
> 
> I think we discussed different options for this behaviour.
> 
> Don't we expect to report the manually set colour temperature if that's
> what was set on that framecontext ? (So that the colour gains match the
> colour temperature or such ?)

Ouch good catch. Thank you. That line shouldn't be there at all. The
metadata gets set a few lines above. Turns out that it was a rebase
error that slipped in in b60bd37b1a49 ("ipa: rkisp1: Move calculation of
RGB means into own function"). I'll fix in v3.

Best regards,
Stefan

> 
> 
> Though I wish there was a way to report both so we can still what the
> autoregulation 'would think' even if it's set to manual...
>   
> >         /*
> >          * Clamp the gain values to the hardware, which expresses gains as Q2.8
> > @@ -333,7 +335,7 @@ void Awb::process(IPAContext &context,
> >                 << std::showpoint
> >                 << "Means " << rgbMeans << ", gains "
> >                 << activeState.awb.automatic.gains << ", temp "
> > -               << activeState.awb.temperatureK << "K";
> > +               << activeState.awb.automatic.temperatureK << "K";
> >  }
> >  
> >  RGB<double> Awb::calculateRgbMeans(const IPAFrameContext &frameContext, const rkisp1_cif_isp_awb_stat *awb) const
> > diff --git a/src/ipa/rkisp1/algorithms/ccm.cpp b/src/ipa/rkisp1/algorithms/ccm.cpp
> > index eb8ca39e56a8..2e5e91006b55 100644
> > --- a/src/ipa/rkisp1/algorithms/ccm.cpp
> > +++ b/src/ipa/rkisp1/algorithms/ccm.cpp
> > @@ -88,7 +88,7 @@ void Ccm::setParameters(struct rkisp1_cif_isp_ctk_config &config,
> >  void Ccm::prepare(IPAContext &context, const uint32_t frame,
> >                   IPAFrameContext &frameContext, RkISP1Params *params)
> >  {
> > -       uint32_t ct = context.activeState.awb.temperatureK;
> > +       uint32_t ct = frameContext.awb.temperatureK;
> 
> 
> Hrm. ... we need to make sure Awb algo always runs before Ccm in this
> instance.
> 
> I think we're "in luck" because of alphabetical sorting, but I think
> this indicates we will need to indicate some sort of dependencies
> between algos...
> 
> 
> 
> >  
> >         /*
> >          * \todo The colour temperature will likely be noisy, add filtering to
> > diff --git a/src/ipa/rkisp1/algorithms/lsc.cpp b/src/ipa/rkisp1/algorithms/lsc.cpp
> > index e47aa2f0727e..e7301bfec863 100644
> > --- a/src/ipa/rkisp1/algorithms/lsc.cpp
> > +++ b/src/ipa/rkisp1/algorithms/lsc.cpp
> > @@ -404,12 +404,12 @@ void LensShadingCorrection::copyTable(rkisp1_cif_isp_lsc_config &config,
> >  /**
> >   * \copydoc libcamera::ipa::Algorithm::prepare
> >   */
> > -void LensShadingCorrection::prepare(IPAContext &context,
> > +void LensShadingCorrection::prepare([[maybe_unused]] IPAContext &context,
> >                                     [[maybe_unused]] const uint32_t frame,
> > -                                   [[maybe_unused]] IPAFrameContext &frameContext,
> > +                                   IPAFrameContext &frameContext,
> >                                     RkISP1Params *params)
> >  {
> > -       uint32_t ct = context.activeState.awb.temperatureK;
> > +       uint32_t ct = frameContext.awb.temperatureK;
> 
> It is a good job Awb begins with 'a'...
> 
> >         if (std::abs(static_cast<int>(ct) - static_cast<int>(lastAppliedCt_)) <
> >             kColourTemperatureChangeThreshhold)
> >                 return;
> > diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h
> > index 6bc922a82971..769e9f114e23 100644
> > --- a/src/ipa/rkisp1/ipa_context.h
> > +++ b/src/ipa/rkisp1/ipa_context.h
> > @@ -91,12 +91,12 @@ struct IPAActiveState {
> >         struct {
> >                 struct AwbState {
> >                         RGB<double> gains;
> > +                       unsigned int temperatureK;
> >                 };
> >  
> >                 AwbState manual;
> >                 AwbState automatic;
> >  
> > -               unsigned int temperatureK;
> >                 bool autoEnabled;
> >         } awb;
> >  
> > -- 
> > 2.43.0
> >


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