1 files changed, 53 insertions, 0 deletions
diff --git a/src/ipa/libipa/exposure_mode_helper.h b/src/ipa/libipa/exposure_mode_helper.h
new file mode 100644
index 00000000..c5be1b67
--- /dev/null
+++ b/src/ipa/libipa/exposure_mode_helper.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Paul Elder <paul.elder@ideasonboard.com>
+ *
+ * Helper class that performs computations relating to exposure
+ */
+
+#pragma once
+
+#include <tuple>
+#include <utility>
+#include <vector>
+
+#include <libcamera/base/span.h>
+#include <libcamera/base/utils.h>
+
+namespace libcamera {
+
+namespace ipa {
+
+class ExposureModeHelper
+{
+public:
+	ExposureModeHelper(const Span<std::pair<utils::Duration, double>> stages);
+	~ExposureModeHelper() = default;
+
+	void setLimits(utils::Duration minExposureTime, utils::Duration maxExposureTime,
+		       double minGain, double maxGain);
+
+	std::tuple<utils::Duration, double, double>
+	splitExposure(utils::Duration exposure) const;
+
+	utils::Duration minExposureTime() const { return minExposureTime_; }
+	utils::Duration maxExposureTime() const { return maxExposureTime_; }
+	double minGain() const { return minGain_; }
+	double maxGain() const { return maxGain_; }
+
+private:
+	utils::Duration clampExposureTime(utils::Duration exposureTime) const;
+	double clampGain(double gain) const;
+
+	std::vector<utils::Duration> exposureTimes_;
+	std::vector<double> gains_;
+
+	utils::Duration minExposureTime_;
+	utils::Duration maxExposureTime_;
+	double minGain_;
+	double maxGain_;
+};
+
+} /* namespace ipa */
+
+} /* namespace libcamera */