ipa: rkisp1: awb: Freeze AWB when means are too small

When the RGB means are too small, gains and color temperature can't be
meaningfully calculated. Freeze the AWB in that case, using the
previously calculated values.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
This commit is contained in:
Laurent Pinchart 2022-09-04 04:21:18 +03:00
parent 7dc60a5a27
commit 9b389ce79e
3 changed files with 20 additions and 1 deletions

View file

@ -31,6 +31,9 @@ namespace ipa::rkisp1::algorithms {
LOG_DEFINE_CATEGORY(RkISP1Awb)
/* Minimum mean value below which AWB can't operate. */
constexpr double kMeanMinThreshold = 2.0;
Awb::Awb()
: rgbMode_(false)
{
@ -263,7 +266,17 @@ void Awb::process(IPAContext &context,
greenMean /= frameContext.awb.gains.green;
blueMean /= frameContext.awb.gains.blue;
frameContext.awb.temperatureK = estimateCCT(redMean, greenMean, blueMean);
/*
* If the means are too small we don't have enough information to
* meaningfully calculate gains. Freeze the algorithm in that case.
*/
if (redMean < kMeanMinThreshold && greenMean < kMeanMinThreshold &&
blueMean < kMeanMinThreshold) {
frameContext.awb.temperatureK = activeState.awb.temperatureK;
return;
}
activeState.awb.temperatureK = estimateCCT(redMean, greenMean, blueMean);
/*
* Estimate the red and blue gains to apply in a grey world. The green
@ -290,6 +303,8 @@ void Awb::process(IPAContext &context,
activeState.awb.gains.automatic.blue = blueGain;
activeState.awb.gains.automatic.green = 1.0;
frameContext.awb.temperatureK = activeState.awb.temperatureK;
LOG(RkISP1Awb, Debug) << std::showpoint
<< "Means [" << redMean << ", " << greenMean << ", " << blueMean
<< "], gains [" << activeState.awb.gains.automatic.red << ", "