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Diffstat (limited to 'src/ipa/raspberrypi/controller/rpi/contrast.cpp')
| -rw-r--r-- | src/ipa/raspberrypi/controller/rpi/contrast.cpp | 181 |
1 files changed, 0 insertions, 181 deletions
diff --git a/src/ipa/raspberrypi/controller/rpi/contrast.cpp b/src/ipa/raspberrypi/controller/rpi/contrast.cpp deleted file mode 100644 index bee1eadd..00000000 --- a/src/ipa/raspberrypi/controller/rpi/contrast.cpp +++ /dev/null @@ -1,181 +0,0 @@ -/* SPDX-License-Identifier: BSD-2-Clause */ -/* - * Copyright (C) 2019, Raspberry Pi Ltd - * - * contrast.cpp - contrast (gamma) control algorithm - */ -#include <stdint.h> - -#include <libcamera/base/log.h> - -#include "../contrast_status.h" -#include "../histogram.h" - -#include "contrast.h" - -using namespace RPiController; -using namespace libcamera; - -LOG_DEFINE_CATEGORY(RPiContrast) - -/* - * This is a very simple control algorithm which simply retrieves the results of - * AGC and AWB via their "status" metadata, and applies digital gain to the - * colour channels in accordance with those instructions. We take care never to - * apply less than unity gains, as that would cause fully saturated pixels to go - * off-white. - */ - -#define NAME "rpi.contrast" - -Contrast::Contrast(Controller *controller) - : ContrastAlgorithm(controller), brightness_(0.0), contrast_(1.0) -{ -} - -char const *Contrast::name() const -{ - return NAME; -} - -int Contrast::read(const libcamera::YamlObject ¶ms) -{ - // enable adaptive enhancement by default - config_.ceEnable = params["ce_enable"].get<int>(1); - // 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 - config_.loLevel = params["lo_level"].get<double>(0.015); - // but don't move by more than this - config_.loMax = params["lo_max"].get<double>(500); - // equivalent values for the top of the histogram... - config_.hiHistogram = params["hi_histogram"].get<double>(0.95); - config_.hiLevel = params["hi_level"].get<double>(0.95); - config_.hiMax = params["hi_max"].get<double>(2000); - return config_.gammaCurve.read(params["gamma_curve"]); -} - -void Contrast::setBrightness(double brightness) -{ - brightness_ = brightness; -} - -void Contrast::setContrast(double contrast) -{ - contrast_ = contrast; -} - -void Contrast::initialise() -{ - /* - * Fill in some default values as Prepare will run before Process gets - * called. - */ - status_.brightness = brightness_; - status_.contrast = contrast_; - status_.gammaCurve = config_.gammaCurve; -} - -void Contrast::prepare(Metadata *imageMetadata) -{ - imageMetadata->set("contrast.status", status_); -} - -Pwl computeStretchCurve(Histogram const &histogram, - ContrastConfig const &config) -{ - Pwl enhance; - enhance.append(0, 0); - /* - * If the start of the histogram is rather empty, try to pull it down a - * bit. - */ - double histLo = histogram.quantile(config.loHistogram) * - (65536 / histogram.bins()); - double levelLo = config.loLevel * 65536; - LOG(RPiContrast, Debug) - << "Move histogram point " << histLo << " to " << levelLo; - histLo = std::max(levelLo, - std::min(65535.0, std::min(histLo, levelLo + config.loMax))); - LOG(RPiContrast, Debug) - << "Final values " << histLo << " -> " << levelLo; - enhance.append(histLo, levelLo); - /* - * Keep the mid-point (median) in the same place, though, to limit the - * apparent amount of global brightness shift. - */ - double mid = histogram.quantile(0.5) * (65536 / histogram.bins()); - enhance.append(mid, mid); - - /* - * If the top to the histogram is empty, try to pull the pixel values - * there up. - */ - double histHi = histogram.quantile(config.hiHistogram) * - (65536 / histogram.bins()); - double levelHi = config.hiLevel * 65536; - LOG(RPiContrast, Debug) - << "Move histogram point " << histHi << " to " << levelHi; - histHi = std::min(levelHi, - std::max(0.0, std::max(histHi, levelHi - config.hiMax))); - LOG(RPiContrast, Debug) - << "Final values " << histHi << " -> " << levelHi; - enhance.append(histHi, levelHi); - enhance.append(65535, 65535); - return enhance; -} - -Pwl applyManualContrast(Pwl const &gammaCurve, double brightness, - double contrast) -{ - Pwl newGammaCurve; - LOG(RPiContrast, Debug) - << "Manual brightness " << brightness << " contrast " << contrast; - gammaCurve.map([&](double x, double y) { - newGammaCurve.append( - x, std::max(0.0, std::min(65535.0, - (y - 32768) * contrast + - 32768 + brightness))); - }); - return newGammaCurve; -} - -void Contrast::process(StatisticsPtr &stats, - [[maybe_unused]] Metadata *imageMetadata) -{ - Histogram &histogram = stats->yHist; - /* - * We look at the histogram and adjust the gamma curve in the following - * ways: 1. Adjust the gamma curve so as to pull the start of the - * histogram down, and possibly push the end up. - */ - Pwl gammaCurve = config_.gammaCurve; - if (config_.ceEnable) { - if (config_.loMax != 0 || config_.hiMax != 0) - gammaCurve = computeStretchCurve(histogram, config_).compose(gammaCurve); - /* - * We could apply other adjustments (e.g. partial equalisation) - * based on the histogram...? - */ - } - /* - * 2. Finally apply any manually selected brightness/contrast - * adjustment. - */ - if (brightness_ != 0 || contrast_ != 1.0) - gammaCurve = applyManualContrast(gammaCurve, brightness_, contrast_); - /* - * And fill in the status for output. Use more points towards the bottom - * of the curve. - */ - status_.brightness = brightness_; - status_.contrast = contrast_; - status_.gammaCurve = std::move(gammaCurve); -} - -/* Register algorithm with the system. */ -static Algorithm *create(Controller *controller) -{ - return (Algorithm *)new Contrast(controller); -} -static RegisterAlgorithm reg(NAME, &create); |