[PATCH 06/15] libipa: awb: Pass lux value to calculateAwb() as unsigned int

[Laurent Pinchart]

Hi Stefan,

On Mon, Feb 24, 2025 at 10:13:33AM +0100, Stefan Klug wrote:
> Hi Laurent,
> 
> Thank you for the patch. 
> 
> On Mon, Feb 24, 2025 at 01:03:54AM +0200, Laurent Pinchart wrote:
> > The lux value can never be negative. Pass it as an unsigned int.
> 
> I don't like unsigned ints outside lowlevel/hardware stuff (size_t maybe
> one exception). They just produce too many ways to create hidden bugs.
> But so be it :-)

I think I recall we discussed pros and cons.

It doesn't address the signedness issue in general, but how about
creating a Lux type ?

> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > ---
> > Do we need a Lux type ? And maybe a ColourTemperature type ?
> > ---
> >  src/ipa/libipa/awb.h         | 2 +-
> >  src/ipa/libipa/awb_bayes.cpp | 2 +-
> >  src/ipa/libipa/awb_bayes.h   | 2 +-
> >  src/ipa/libipa/awb_grey.cpp  | 2 +-
> >  src/ipa/libipa/awb_grey.h    | 2 +-
> >  5 files changed, 5 insertions(+), 5 deletions(-)
> > 
> > diff --git a/src/ipa/libipa/awb.h b/src/ipa/libipa/awb.h
> > index 4a1b012a4334..5c298d3b6f69 100644
> > --- a/src/ipa/libipa/awb.h
> > +++ b/src/ipa/libipa/awb.h
> > @@ -35,7 +35,7 @@ public:
> >  	virtual ~AwbAlgorithm() = default;
> >  
> >  	virtual int init(const YamlObject &tuningData) = 0;
> > -	virtual AwbResult calculateAwb(const AwbStats &stats, int lux) = 0;
> > +	virtual AwbResult calculateAwb(const AwbStats &stats, unsigned int lux) = 0;
> >  	virtual RGB<double> gainsFromColourTemperature(double colourTemperature) = 0;
> >  
> >  	const ControlInfoMap::Map &controls() const
> > diff --git a/src/ipa/libipa/awb_bayes.cpp b/src/ipa/libipa/awb_bayes.cpp
> > index e75bfcd693d9..9287b884cb95 100644
> > --- a/src/ipa/libipa/awb_bayes.cpp
> > +++ b/src/ipa/libipa/awb_bayes.cpp
> > @@ -275,7 +275,7 @@ RGB<double> AwbBayes::gainsFromColourTemperature(double colourTemperature)
> >  	return { { gains[0], 1.0, gains[1] } };
> >  }
> >  
> > -AwbResult AwbBayes::calculateAwb(const AwbStats &stats, int lux)
> > +AwbResult AwbBayes::calculateAwb(const AwbStats &stats, unsigned int lux)
> >  {
> >  	ipa::Pwl prior;
> >  	if (lux > 0) {
> 
> This if clause should then be removed, too.

No, this tests for > 0, not >= 0. 0 is still a magic value. a
std::optional<unsigned int> would express that better if we want to go
that way.

> > diff --git a/src/ipa/libipa/awb_bayes.h b/src/ipa/libipa/awb_bayes.h
> > index 47db7243273f..23bf88061118 100644
> > --- a/src/ipa/libipa/awb_bayes.h
> > +++ b/src/ipa/libipa/awb_bayes.h
> > @@ -34,7 +34,7 @@ public:
> >  	AwbBayes() = default;
> >  
> >  	int init(const YamlObject &tuningData) override;
> > -	AwbResult calculateAwb(const AwbStats &stats, int lux) override;
> > +	AwbResult calculateAwb(const AwbStats &stats, unsigned int lux) override;
> >  	RGB<double> gainsFromColourTemperature(double temperatureK) override;
> >  	void handleControls(const ControlList &controls) override;
> >  
> > diff --git a/src/ipa/libipa/awb_grey.cpp b/src/ipa/libipa/awb_grey.cpp
> > index 06ffd45618d8..e979cc4d1a3e 100644
> > --- a/src/ipa/libipa/awb_grey.cpp
> > +++ b/src/ipa/libipa/awb_grey.cpp
> > @@ -70,7 +70,7 @@ int AwbGrey::init(const YamlObject &tuningData)
> >   *
> >   * \return The AWB result
> >   */
> > -AwbResult AwbGrey::calculateAwb(const AwbStats &stats, [[maybe_unused]] int lux)
> > +AwbResult AwbGrey::calculateAwb(const AwbStats &stats, [[maybe_unused]] unsigned int lux)
> >  {
> >  	AwbResult result;
> >  	auto means = stats.getRGBMeans();
> > diff --git a/src/ipa/libipa/awb_grey.h b/src/ipa/libipa/awb_grey.h
> > index 1a365e616a98..e3c34201dbc9 100644
> > --- a/src/ipa/libipa/awb_grey.h
> > +++ b/src/ipa/libipa/awb_grey.h
> > @@ -23,7 +23,7 @@ public:
> >  	AwbGrey() = default;
> >  
> >  	int init(const YamlObject &tuningData) override;
> > -	AwbResult calculateAwb(const AwbStats &stats, int lux) override;
> > +	AwbResult calculateAwb(const AwbStats &stats, unsigned int lux) override;
> >  	RGB<double> gainsFromColourTemperature(double colourTemperature) override;
> >  
> >  private:

-- 
Regards,

Laurent Pinchart