ipa: rpi: contrast: Allow adaptive contrast enhancement to be disabled

The enableCe() function enables or disables adaptive contrast
enhancement and the restoreCe() function sets it back to its normal
state (which is what was read from the tuning file).

In future, algorithms like HDR might want to take over tonemapping
functions, so any dynamic behaviour here would upset them.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
Reviewed-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/src/ipa/rpi/controller/rpi/contrast.cpp b/src/ipa/rpi/controller/rpi/contrast.cpp
index bee1eadd..4e038a02 100644
--- a/src/ipa/rpi/controller/rpi/contrast.cpp
+++ b/src/ipa/rpi/controller/rpi/contrast.cpp
@@ -42,6 +42,7 @@ int Contrast::read(const libcamera::YamlObject &params)
 {
 	// enable adaptive enhancement by default
 	config_.ceEnable = params["ce_enable"].get<int>(1);
+	ceEnable_ = config_.ceEnable;
 	// the point near the bottom of the histogram to move
 	config_.loHistogram = params["lo_histogram"].get<double>(0.01);
 	// where in the range to try and move it to
@@ -65,6 +66,16 @@ void Contrast::setContrast(double contrast)
 	contrast_ = contrast;
 }
 
+void Contrast::enableCe(bool enable)
+{
+	ceEnable_ = enable;
+}
+
+void Contrast::restoreCe()
+{
+	ceEnable_ = config_.ceEnable;
+}
+
 void Contrast::initialise()
 {
 	/*
@@ -150,7 +161,7 @@ void Contrast::process(StatisticsPtr &stats,
 	 * histogram down, and possibly push the end up.
 	 */
 	Pwl gammaCurve = config_.gammaCurve;
-	if (config_.ceEnable) {
+	if (ceEnable_) {
 		if (config_.loMax != 0 || config_.hiMax != 0)
 			gammaCurve = computeStretchCurve(histogram, config_).compose(gammaCurve);
 		/*