From 290ebeb59525eb7fdcc6f815d8dee6cbe3d8a314 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Thu, 8 Sep 2022 00:39:53 +0300 Subject: ipa: rkisp1: awb: Use frame context to fix gains calculations The AWB statistics are computed after the ISP applies the colour gains. This means that the red, green and blue means do not match the data coming directly from the sensor, but are multiplied by the colour gains that were used for the frame on which the statistics have been computed. The AWB algorithm needs to take this into account when calculating the colour gains for the next frame. Do so by dividing the means by the gains that were applied to the frame, retrieved from the frame context. Signed-off-by: Laurent Pinchart Reviewed-by: Kieran Bingham Reviewed-by: Jacopo Mondi --- src/ipa/rkisp1/algorithms/awb.cpp | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'src/ipa') diff --git a/src/ipa/rkisp1/algorithms/awb.cpp b/src/ipa/rkisp1/algorithms/awb.cpp index e491cf75..694d97cc 100644 --- a/src/ipa/rkisp1/algorithms/awb.cpp +++ b/src/ipa/rkisp1/algorithms/awb.cpp @@ -207,6 +207,15 @@ void Awb::process(IPAContext &context, double greenMean = 1.1636 * yMean - 0.4045 * cbMean - 0.7949 * crMean; double blueMean = 1.1636 * yMean + 1.9912 * cbMean - 0.0250 * crMean; + /* + * The ISP computes the AWB means after applying the colour gains, + * divide by the gains that were used to get the raw means from the + * sensor. + */ + redMean /= frameContext.awb.gains.red; + greenMean /= frameContext.awb.gains.green; + blueMean /= frameContext.awb.gains.blue; + frameContext.awb.temperatureK = estimateCCT(redMean, greenMean, blueMean); /* Estimate the red and blue gains to apply in a grey world. */ -- cgit v1.2.1