From 84f82c6b3ca9c90d6fc8e55678a39968f16b255c Mon Sep 17 00:00:00 2001 From: Milan Zamazal Date: Wed, 26 Mar 2025 10:08:38 +0100 Subject: libcamera: software_isp: Determine color temperature The AWB algorithm has data to determine color temperature of the image. Let's compute the temperature from it and store it into the context. This piece of information is currently unused but it will be needed in a followup patch introducing support for color correction matrix. Let's store the white balance related information under `awb' subsection of the active state, as the hardware pipelines do. Signed-off-by: Milan Zamazal Reviewed-by: Kieran Bingham Reviewed-by: Laurent Pinchart Signed-off-by: Milan Zamazal Signed-off-by: Kieran Bingham --- src/ipa/simple/algorithms/awb.cpp | 12 +++++++++--- src/ipa/simple/algorithms/lut.cpp | 2 +- 2 files changed, 10 insertions(+), 4 deletions(-) (limited to 'src/ipa/simple/algorithms') diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp index 195de41d..1efc7090 100644 --- a/src/ipa/simple/algorithms/awb.cpp +++ b/src/ipa/simple/algorithms/awb.cpp @@ -12,6 +12,7 @@ #include +#include "libipa/colours.h" #include "simple/ipa_context.h" namespace libcamera { @@ -23,7 +24,7 @@ namespace ipa::soft::algorithms { int Awb::configure(IPAContext &context, [[maybe_unused]] const IPAConfigInfo &configInfo) { - auto &gains = context.activeState.gains; + auto &gains = context.activeState.awb.gains; gains.red = gains.green = gains.blue = 1.0; return 0; @@ -54,12 +55,17 @@ void Awb::process(IPAContext &context, * Calculate red and blue gains for AWB. * Clamp max gain at 4.0, this also avoids 0 division. */ - auto &gains = context.activeState.gains; + auto &gains = context.activeState.awb.gains; gains.red = sumR <= sumG / 4 ? 4.0 : static_cast(sumG) / sumR; gains.blue = sumB <= sumG / 4 ? 4.0 : static_cast(sumG) / sumB; /* Green gain is fixed to 1.0 */ - LOG(IPASoftAwb, Debug) << "gain R/B " << gains.red << "/" << gains.blue; + RGB rgbGains{ { 1 / gains.red, 1 / gains.green, 1 / gains.blue } }; + context.activeState.awb.temperatureK = estimateCCT(rgbGains); + + LOG(IPASoftAwb, Debug) + << "gain R/B: " << gains.red << "/" << gains.blue + << "; temperature: " << context.activeState.awb.temperatureK; } REGISTER_IPA_ALGORITHM(Awb, "Awb") diff --git a/src/ipa/simple/algorithms/lut.cpp b/src/ipa/simple/algorithms/lut.cpp index 18f3a550..a2e11d3b 100644 --- a/src/ipa/simple/algorithms/lut.cpp +++ b/src/ipa/simple/algorithms/lut.cpp @@ -95,7 +95,7 @@ void Lut::prepare(IPAContext &context, context.activeState.gamma.contrast != context.activeState.knobs.contrast) updateGammaTable(context); - auto &gains = context.activeState.gains; + auto &gains = context.activeState.awb.gains; auto &gammaTable = context.activeState.gamma.gammaTable; const unsigned int gammaTableSize = gammaTable.size(); -- cgit v1.2.1