ipa: libipa: colour: Use the RGB class to model RGB values

The rec601LuminanceFromRGB() and estimateCCT() functions take RGB
triplets as three variables. Replace them with instances of the RGB
class and adapt the users accordingly. Only variables passed directly to
these functions are converted to RGB instances, further conversion of
IPA modules to the RGB class will be performed separately.

While at it, fix a typo in the documentation of the estimateCCT()
function.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Milan Zamazal <mzamazal@redhat.com>

2 files changed, 7 insertions, 9 deletions

diff --git a/src/ipa/ipu3/algorithms/agc.cpp b/src/ipa/ipu3/algorithms/agc.cpp
index 46669203..39d0aebb 100644
--- a/src/ipa/ipu3/algorithms/agc.cpp
+++ b/src/ipa/ipu3/algorithms/agc.cpp
@@ -178,18 +178,16 @@ Histogram Agc::parseStatistics(const ipu3_uapi_stats_3a *stats,
  */
 double Agc::estimateLuminance(double gain) const
 {
-	double redSum = 0, greenSum = 0, blueSum = 0;
+	RGB<double> sum{ 0.0 };
 
 	for (unsigned int i = 0; i < rgbTriples_.size(); i++) {
-		redSum += std::min(std::get<0>(rgbTriples_[i]) * gain, 255.0);
-		greenSum += std::min(std::get<1>(rgbTriples_[i]) * gain, 255.0);
-		blueSum += std::min(std::get<2>(rgbTriples_[i]) * gain, 255.0);
+		sum.r() += std::min(std::get<0>(rgbTriples_[i]) * gain, 255.0);
+		sum.g() += std::min(std::get<1>(rgbTriples_[i]) * gain, 255.0);
+		sum.b() += std::min(std::get<2>(rgbTriples_[i]) * gain, 255.0);
 	}
 
-	double ySum = rec601LuminanceFromRGB(redSum * rGain_,
-					     greenSum * gGain_,
-					     blueSum * bGain_);
-
+	RGB<double> gains{{ rGain_, gGain_, bGain_ }};
+	double ySum = rec601LuminanceFromRGB(sum * gains);
 	return ySum / (bdsGrid_.height * bdsGrid_.width) / 255;
 }
 
diff --git a/src/ipa/ipu3/algorithms/awb.cpp b/src/ipa/ipu3/algorithms/awb.cpp
index 7c6bff09..55de05d9 100644
--- a/src/ipa/ipu3/algorithms/awb.cpp
+++ b/src/ipa/ipu3/algorithms/awb.cpp
@@ -412,7 +412,7 @@ void Awb::awbGreyWorld()
 	       blueGain = sumBlue.g() / (sumBlue.b() + 1);
 
 	/* Color temperature is not relevant in Grey world but still useful to estimate it :-) */
-	asyncResults_.temperatureK = estimateCCT(sumRed.r(), sumRed.g(), sumBlue.b());
+	asyncResults_.temperatureK = estimateCCT({{ sumRed.r(), sumRed.g(), sumBlue.b() }});
 
 	/*
 	 * Gain values are unsigned integer value ranging [0, 8) with 13 bit