From 0db2c8dc75e466e7648dc1b95380495c6a126349 Mon Sep 17 00:00:00 2001 From: Naushir Patuck Date: Sun, 3 May 2020 16:48:42 +0100 Subject: libcamera: ipa: Raspberry Pi IPA Initial implementation of the Raspberry Pi (BCM2835) libcamera IPA and associated libraries. All code is licensed under the BSD-2-Clause terms. Copyright (c) 2019-2020 Raspberry Pi Trading Ltd. Signed-off-by: Naushir Patuck Acked-by: Laurent Pinchart Signed-off-by: Laurent Pinchart --- src/ipa/raspberrypi/controller/histogram.hpp | 44 ++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 src/ipa/raspberrypi/controller/histogram.hpp (limited to 'src/ipa/raspberrypi/controller/histogram.hpp') diff --git a/src/ipa/raspberrypi/controller/histogram.hpp b/src/ipa/raspberrypi/controller/histogram.hpp new file mode 100644 index 00000000..06fc3aa7 --- /dev/null +++ b/src/ipa/raspberrypi/controller/histogram.hpp @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ +/* + * Copyright (C) 2019, Raspberry Pi (Trading) Limited + * + * histogram.hpp - histogram calculation interface + */ +#pragma once + +#include +#include +#include + +// A simple histogram class, for use in particular to find "quantiles" and +// averages between "quantiles". + +namespace RPi { + +class Histogram +{ +public: + template Histogram(T *histogram, int num) + { + assert(num); + cumulative_.reserve(num + 1); + cumulative_.push_back(0); + for (int i = 0; i < num; i++) + cumulative_.push_back(cumulative_.back() + + histogram[i]); + } + uint32_t Bins() const { return cumulative_.size() - 1; } + uint64_t Total() const { return cumulative_[cumulative_.size() - 1]; } + // Cumulative frequency up to a (fractional) point in a bin. + uint64_t CumulativeFreq(double bin) const; + // Return the (fractional) bin of the point q (0 <= q <= 1) through the + // histogram. Optionally provide limits to help. + double Quantile(double q, int first = -1, int last = -1) const; + // Return the average histogram bin value between the two quantiles. + double InterQuantileMean(double q_lo, double q_hi) const; + +private: + std::vector cumulative_; +}; + +} // namespace RPi -- cgit v1.2.1