From 9b389ce79eb143a82e998bfe5b09470272a25600 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sun, 4 Sep 2022 04:21:18 +0300 Subject: 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 Reviewed-by: Kieran Bingham Reviewed-by: Jacopo Mondi --- src/ipa/rkisp1/algorithms/awb.cpp | 17 ++++++++++++++++- src/ipa/rkisp1/ipa_context.cpp | 3 +++ src/ipa/rkisp1/ipa_context.h | 1 + 3 files changed, 20 insertions(+), 1 deletion(-) diff --git a/src/ipa/rkisp1/algorithms/awb.cpp b/src/ipa/rkisp1/algorithms/awb.cpp index a3066fbb..eb32cd72 100644 --- a/src/ipa/rkisp1/algorithms/awb.cpp +++ b/src/ipa/rkisp1/algorithms/awb.cpp @@ -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 << ", " diff --git a/src/ipa/rkisp1/ipa_context.cpp b/src/ipa/rkisp1/ipa_context.cpp index 2126ed1d..b00dc29c 100644 --- a/src/ipa/rkisp1/ipa_context.cpp +++ b/src/ipa/rkisp1/ipa_context.cpp @@ -156,6 +156,9 @@ namespace libcamera::ipa::rkisp1 { * \var IPAActiveState::awb.gains.automatic.blue * \brief Automatic white balance gain for B channel * + * \var IPAActiveState::awb.temperatureK + * \brief Estimated color temperature + * * \var IPAActiveState::awb.autoEnabled * \brief Whether the Auto White Balance algorithm is enabled */ diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h index ad357f25..c85d8abe 100644 --- a/src/ipa/rkisp1/ipa_context.h +++ b/src/ipa/rkisp1/ipa_context.h @@ -68,6 +68,7 @@ struct IPAActiveState { } automatic; } gains; + unsigned int temperatureK; bool autoEnabled; } awb; -- cgit v1.2.1