diff options
author | Naushir Patuck <naush@raspberrypi.com> | 2023-05-03 13:20:27 +0100 |
---|---|---|
committer | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2023-05-04 20:47:40 +0300 |
commit | 726e9274ea95fa46352556d340c5793a8da51fcd (patch) | |
tree | 80f6adcdbf744f9317e09eff3e80c602b384a753 /src/ipa/raspberrypi/controller/rpi/agc.cpp | |
parent | 46aefed208fef4bc8d6f6e8882b92b9af710a60b (diff) |
pipeline: ipa: raspberrypi: Refactor and move the Raspberry Pi code
Split the Raspberry Pi pipeline handler and IPA source code into common
and VC4/BCM2835 specific file structures.
For the pipeline handler, the common code files now live in
src/libcamera/pipeline/rpi/common/
and the VC4-specific files in src/libcamera/pipeline/rpi/vc4/.
For the IPA, the common code files now live in
src/ipa/rpi/{cam_helper,controller}/
and the vc4 specific files in src/ipa/rpi/vc4/. With this change, the
camera tuning files are now installed under share/libcamera/ipa/rpi/vc4/.
To build the pipeline and IPA, the meson configuration options have now
changed from "raspberrypi" to "rpi/vc4":
meson setup build -Dipas=rpi/vc4 -Dpipelines=rpi/vc4
Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Diffstat (limited to 'src/ipa/raspberrypi/controller/rpi/agc.cpp')
-rw-r--r-- | src/ipa/raspberrypi/controller/rpi/agc.cpp | 922 |
1 files changed, 0 insertions, 922 deletions
diff --git a/src/ipa/raspberrypi/controller/rpi/agc.cpp b/src/ipa/raspberrypi/controller/rpi/agc.cpp deleted file mode 100644 index e6fb7b8d..00000000 --- a/src/ipa/raspberrypi/controller/rpi/agc.cpp +++ /dev/null @@ -1,922 +0,0 @@ -/* SPDX-License-Identifier: BSD-2-Clause */ -/* - * Copyright (C) 2019, Raspberry Pi Ltd - * - * agc.cpp - AGC/AEC control algorithm - */ - -#include <algorithm> -#include <map> -#include <tuple> - -#include <libcamera/base/log.h> - -#include "../awb_status.h" -#include "../device_status.h" -#include "../histogram.h" -#include "../lux_status.h" -#include "../metadata.h" - -#include "agc.h" - -using namespace RPiController; -using namespace libcamera; -using libcamera::utils::Duration; -using namespace std::literals::chrono_literals; - -LOG_DEFINE_CATEGORY(RPiAgc) - -#define NAME "rpi.agc" - -int AgcMeteringMode::read(const libcamera::YamlObject ¶ms) -{ - const YamlObject &yamlWeights = params["weights"]; - - for (const auto &p : yamlWeights.asList()) { - auto value = p.get<double>(); - if (!value) - return -EINVAL; - weights.push_back(*value); - } - - return 0; -} - -static std::tuple<int, std::string> -readMeteringModes(std::map<std::string, AgcMeteringMode> &metering_modes, - const libcamera::YamlObject ¶ms) -{ - std::string first; - int ret; - - for (const auto &[key, value] : params.asDict()) { - AgcMeteringMode meteringMode; - ret = meteringMode.read(value); - if (ret) - return { ret, {} }; - - metering_modes[key] = std::move(meteringMode); - if (first.empty()) - first = key; - } - - return { 0, first }; -} - -int AgcExposureMode::read(const libcamera::YamlObject ¶ms) -{ - auto value = params["shutter"].getList<double>(); - if (!value) - return -EINVAL; - std::transform(value->begin(), value->end(), std::back_inserter(shutter), - [](double v) { return v * 1us; }); - - value = params["gain"].getList<double>(); - if (!value) - return -EINVAL; - gain = std::move(*value); - - if (shutter.size() < 2 || gain.size() < 2) { - LOG(RPiAgc, Error) - << "AgcExposureMode: must have at least two entries in exposure profile"; - return -EINVAL; - } - - if (shutter.size() != gain.size()) { - LOG(RPiAgc, Error) - << "AgcExposureMode: expect same number of exposure and gain entries in exposure profile"; - return -EINVAL; - } - - return 0; -} - -static std::tuple<int, std::string> -readExposureModes(std::map<std::string, AgcExposureMode> &exposureModes, - const libcamera::YamlObject ¶ms) -{ - std::string first; - int ret; - - for (const auto &[key, value] : params.asDict()) { - AgcExposureMode exposureMode; - ret = exposureMode.read(value); - if (ret) - return { ret, {} }; - - exposureModes[key] = std::move(exposureMode); - if (first.empty()) - first = key; - } - - return { 0, first }; -} - -int AgcConstraint::read(const libcamera::YamlObject ¶ms) -{ - std::string boundString = params["bound"].get<std::string>(""); - transform(boundString.begin(), boundString.end(), - boundString.begin(), ::toupper); - if (boundString != "UPPER" && boundString != "LOWER") { - LOG(RPiAgc, Error) << "AGC constraint type should be UPPER or LOWER"; - return -EINVAL; - } - bound = boundString == "UPPER" ? Bound::UPPER : Bound::LOWER; - - auto value = params["q_lo"].get<double>(); - if (!value) - return -EINVAL; - qLo = *value; - - value = params["q_hi"].get<double>(); - if (!value) - return -EINVAL; - qHi = *value; - - return yTarget.read(params["y_target"]); -} - -static std::tuple<int, AgcConstraintMode> -readConstraintMode(const libcamera::YamlObject ¶ms) -{ - AgcConstraintMode mode; - int ret; - - for (const auto &p : params.asList()) { - AgcConstraint constraint; - ret = constraint.read(p); - if (ret) - return { ret, {} }; - - mode.push_back(std::move(constraint)); - } - - return { 0, mode }; -} - -static std::tuple<int, std::string> -readConstraintModes(std::map<std::string, AgcConstraintMode> &constraintModes, - const libcamera::YamlObject ¶ms) -{ - std::string first; - int ret; - - for (const auto &[key, value] : params.asDict()) { - std::tie(ret, constraintModes[key]) = readConstraintMode(value); - if (ret) - return { ret, {} }; - - if (first.empty()) - first = key; - } - - return { 0, first }; -} - -int AgcConfig::read(const libcamera::YamlObject ¶ms) -{ - LOG(RPiAgc, Debug) << "AgcConfig"; - int ret; - - std::tie(ret, defaultMeteringMode) = - readMeteringModes(meteringModes, params["metering_modes"]); - if (ret) - return ret; - std::tie(ret, defaultExposureMode) = - readExposureModes(exposureModes, params["exposure_modes"]); - if (ret) - return ret; - std::tie(ret, defaultConstraintMode) = - readConstraintModes(constraintModes, params["constraint_modes"]); - if (ret) - return ret; - - ret = yTarget.read(params["y_target"]); - if (ret) - return ret; - - speed = params["speed"].get<double>(0.2); - startupFrames = params["startup_frames"].get<uint16_t>(10); - convergenceFrames = params["convergence_frames"].get<unsigned int>(6); - fastReduceThreshold = params["fast_reduce_threshold"].get<double>(0.4); - baseEv = params["base_ev"].get<double>(1.0); - - /* Start with quite a low value as ramping up is easier than ramping down. */ - defaultExposureTime = params["default_exposure_time"].get<double>(1000) * 1us; - defaultAnalogueGain = params["default_analogue_gain"].get<double>(1.0); - - return 0; -} - -Agc::ExposureValues::ExposureValues() - : shutter(0s), analogueGain(0), - totalExposure(0s), totalExposureNoDG(0s) -{ -} - -Agc::Agc(Controller *controller) - : AgcAlgorithm(controller), meteringMode_(nullptr), - exposureMode_(nullptr), constraintMode_(nullptr), - frameCount_(0), lockCount_(0), - lastTargetExposure_(0s), ev_(1.0), flickerPeriod_(0s), - maxShutter_(0s), fixedShutter_(0s), fixedAnalogueGain_(0.0) -{ - memset(&awb_, 0, sizeof(awb_)); - /* - * Setting status_.totalExposureValue_ to zero initially tells us - * it's not been calculated yet (i.e. Process hasn't yet run). - */ - memset(&status_, 0, sizeof(status_)); - status_.ev = ev_; -} - -char const *Agc::name() const -{ - return NAME; -} - -int Agc::read(const libcamera::YamlObject ¶ms) -{ - LOG(RPiAgc, Debug) << "Agc"; - - int ret = config_.read(params); - if (ret) - return ret; - - const Size &size = getHardwareConfig().agcZoneWeights; - for (auto const &modes : config_.meteringModes) { - if (modes.second.weights.size() != size.width * size.height) { - LOG(RPiAgc, Error) << "AgcMeteringMode: Incorrect number of weights"; - return -EINVAL; - } - } - - /* - * Set the config's defaults (which are the first ones it read) as our - * current modes, until someone changes them. (they're all known to - * exist at this point) - */ - meteringModeName_ = config_.defaultMeteringMode; - meteringMode_ = &config_.meteringModes[meteringModeName_]; - exposureModeName_ = config_.defaultExposureMode; - exposureMode_ = &config_.exposureModes[exposureModeName_]; - constraintModeName_ = config_.defaultConstraintMode; - constraintMode_ = &config_.constraintModes[constraintModeName_]; - /* Set up the "last shutter/gain" values, in case AGC starts "disabled". */ - status_.shutterTime = config_.defaultExposureTime; - status_.analogueGain = config_.defaultAnalogueGain; - return 0; -} - -void Agc::disableAuto() -{ - fixedShutter_ = status_.shutterTime; - fixedAnalogueGain_ = status_.analogueGain; -} - -void Agc::enableAuto() -{ - fixedShutter_ = 0s; - fixedAnalogueGain_ = 0; -} - -unsigned int Agc::getConvergenceFrames() const -{ - /* - * If shutter and gain have been explicitly set, there is no - * convergence to happen, so no need to drop any frames - return zero. - */ - if (fixedShutter_ && fixedAnalogueGain_) - return 0; - else - return config_.convergenceFrames; -} - -void Agc::setEv(double ev) -{ - ev_ = ev; -} - -void Agc::setFlickerPeriod(Duration flickerPeriod) -{ - flickerPeriod_ = flickerPeriod; -} - -void Agc::setMaxShutter(Duration maxShutter) -{ - maxShutter_ = maxShutter; -} - -void Agc::setFixedShutter(Duration fixedShutter) -{ - fixedShutter_ = fixedShutter; - /* Set this in case someone calls disableAuto() straight after. */ - status_.shutterTime = limitShutter(fixedShutter_); -} - -void Agc::setFixedAnalogueGain(double fixedAnalogueGain) -{ - fixedAnalogueGain_ = fixedAnalogueGain; - /* Set this in case someone calls disableAuto() straight after. */ - status_.analogueGain = limitGain(fixedAnalogueGain); -} - -void Agc::setMeteringMode(std::string const &meteringModeName) -{ - meteringModeName_ = meteringModeName; -} - -void Agc::setExposureMode(std::string const &exposureModeName) -{ - exposureModeName_ = exposureModeName; -} - -void Agc::setConstraintMode(std::string const &constraintModeName) -{ - constraintModeName_ = constraintModeName; -} - -void Agc::switchMode(CameraMode const &cameraMode, - Metadata *metadata) -{ - /* AGC expects the mode sensitivity always to be non-zero. */ - ASSERT(cameraMode.sensitivity); - - housekeepConfig(); - - /* - * Store the mode in the local state. We must cache the sensitivity of - * of the previous mode for the calculations below. - */ - double lastSensitivity = mode_.sensitivity; - mode_ = cameraMode; - - Duration fixedShutter = limitShutter(fixedShutter_); - if (fixedShutter && fixedAnalogueGain_) { - /* We're going to reset the algorithm here with these fixed values. */ - - fetchAwbStatus(metadata); - double minColourGain = std::min({ awb_.gainR, awb_.gainG, awb_.gainB, 1.0 }); - ASSERT(minColourGain != 0.0); - - /* This is the equivalent of computeTargetExposure and applyDigitalGain. */ - target_.totalExposureNoDG = fixedShutter_ * fixedAnalogueGain_; - target_.totalExposure = target_.totalExposureNoDG / minColourGain; - - /* Equivalent of filterExposure. This resets any "history". */ - filtered_ = target_; - - /* Equivalent of divideUpExposure. */ - filtered_.shutter = fixedShutter; - filtered_.analogueGain = fixedAnalogueGain_; - } else if (status_.totalExposureValue) { - /* - * On a mode switch, various things could happen: - * - the exposure profile might change - * - a fixed exposure or gain might be set - * - the new mode's sensitivity might be different - * We cope with the last of these by scaling the target values. After - * that we just need to re-divide the exposure/gain according to the - * current exposure profile, which takes care of everything else. - */ - - double ratio = lastSensitivity / cameraMode.sensitivity; - target_.totalExposureNoDG *= ratio; - target_.totalExposure *= ratio; - filtered_.totalExposureNoDG *= ratio; - filtered_.totalExposure *= ratio; - - divideUpExposure(); - } else { - /* - * We come through here on startup, when at least one of the shutter - * or gain has not been fixed. We must still write those values out so - * that they will be applied immediately. We supply some arbitrary defaults - * for any that weren't set. - */ - - /* Equivalent of divideUpExposure. */ - filtered_.shutter = fixedShutter ? fixedShutter : config_.defaultExposureTime; - filtered_.analogueGain = fixedAnalogueGain_ ? fixedAnalogueGain_ : config_.defaultAnalogueGain; - } - - writeAndFinish(metadata, false); -} - -void Agc::prepare(Metadata *imageMetadata) -{ - Duration totalExposureValue = status_.totalExposureValue; - AgcStatus delayedStatus; - - if (!imageMetadata->get("agc.delayed_status", delayedStatus)) - totalExposureValue = delayedStatus.totalExposureValue; - - status_.digitalGain = 1.0; - fetchAwbStatus(imageMetadata); /* always fetch it so that Process knows it's been done */ - - if (status_.totalExposureValue) { - /* Process has run, so we have meaningful values. */ - DeviceStatus deviceStatus; - if (imageMetadata->get("device.status", deviceStatus) == 0) { - Duration actualExposure = deviceStatus.shutterSpeed * - deviceStatus.analogueGain; - if (actualExposure) { - status_.digitalGain = totalExposureValue / actualExposure; - LOG(RPiAgc, Debug) << "Want total exposure " << totalExposureValue; - /* - * Never ask for a gain < 1.0, and also impose - * some upper limit. Make it customisable? - */ - status_.digitalGain = std::max(1.0, std::min(status_.digitalGain, 4.0)); - LOG(RPiAgc, Debug) << "Actual exposure " << actualExposure; - LOG(RPiAgc, Debug) << "Use digitalGain " << status_.digitalGain; - LOG(RPiAgc, Debug) << "Effective exposure " - << actualExposure * status_.digitalGain; - /* Decide whether AEC/AGC has converged. */ - updateLockStatus(deviceStatus); - } - } else - LOG(RPiAgc, Warning) << name() << ": no device metadata"; - imageMetadata->set("agc.status", status_); - } -} - -void Agc::process(StatisticsPtr &stats, Metadata *imageMetadata) -{ - frameCount_++; - /* - * First a little bit of housekeeping, fetching up-to-date settings and - * configuration, that kind of thing. - */ - housekeepConfig(); - /* Get the current exposure values for the frame that's just arrived. */ - fetchCurrentExposure(imageMetadata); - /* Compute the total gain we require relative to the current exposure. */ - double gain, targetY; - computeGain(stats, imageMetadata, gain, targetY); - /* Now compute the target (final) exposure which we think we want. */ - computeTargetExposure(gain); - /* - * Some of the exposure has to be applied as digital gain, so work out - * what that is. This function also tells us whether it's decided to - * "desaturate" the image more quickly. - */ - bool desaturate = applyDigitalGain(gain, targetY); - /* The results have to be filtered so as not to change too rapidly. */ - filterExposure(desaturate); - /* - * The last thing is to divide up the exposure value into a shutter time - * and analogue gain, according to the current exposure mode. - */ - divideUpExposure(); - /* Finally advertise what we've done. */ - writeAndFinish(imageMetadata, desaturate); -} - -void Agc::updateLockStatus(DeviceStatus const &deviceStatus) -{ - const double errorFactor = 0.10; /* make these customisable? */ - const int maxLockCount = 5; - /* Reset "lock count" when we exceed this multiple of errorFactor */ - const double resetMargin = 1.5; - - /* Add 200us to the exposure time error to allow for line quantisation. */ - Duration exposureError = lastDeviceStatus_.shutterSpeed * errorFactor + 200us; - double gainError = lastDeviceStatus_.analogueGain * errorFactor; - Duration targetError = lastTargetExposure_ * errorFactor; - - /* - * Note that we don't know the exposure/gain limits of the sensor, so - * the values we keep requesting may be unachievable. For this reason - * we only insist that we're close to values in the past few frames. - */ - if (deviceStatus.shutterSpeed > lastDeviceStatus_.shutterSpeed - exposureError && - deviceStatus.shutterSpeed < lastDeviceStatus_.shutterSpeed + exposureError && - deviceStatus.analogueGain > lastDeviceStatus_.analogueGain - gainError && - deviceStatus.analogueGain < lastDeviceStatus_.analogueGain + gainError && - status_.targetExposureValue > lastTargetExposure_ - targetError && - status_.targetExposureValue < lastTargetExposure_ + targetError) - lockCount_ = std::min(lockCount_ + 1, maxLockCount); - else if (deviceStatus.shutterSpeed < lastDeviceStatus_.shutterSpeed - resetMargin * exposureError || - deviceStatus.shutterSpeed > lastDeviceStatus_.shutterSpeed + resetMargin * exposureError || - deviceStatus.analogueGain < lastDeviceStatus_.analogueGain - resetMargin * gainError || - deviceStatus.analogueGain > lastDeviceStatus_.analogueGain + resetMargin * gainError || - status_.targetExposureValue < lastTargetExposure_ - resetMargin * targetError || - status_.targetExposureValue > lastTargetExposure_ + resetMargin * targetError) - lockCount_ = 0; - - lastDeviceStatus_ = deviceStatus; - lastTargetExposure_ = status_.targetExposureValue; - - LOG(RPiAgc, Debug) << "Lock count updated to " << lockCount_; - status_.locked = lockCount_ == maxLockCount; -} - -static void copyString(std::string const &s, char *d, size_t size) -{ - size_t length = s.copy(d, size - 1); - d[length] = '\0'; -} - -void Agc::housekeepConfig() -{ - /* First fetch all the up-to-date settings, so no one else has to do it. */ - status_.ev = ev_; - status_.fixedShutter = limitShutter(fixedShutter_); - status_.fixedAnalogueGain = fixedAnalogueGain_; - status_.flickerPeriod = flickerPeriod_; - LOG(RPiAgc, Debug) << "ev " << status_.ev << " fixedShutter " - << status_.fixedShutter << " fixedAnalogueGain " - << status_.fixedAnalogueGain; - /* - * Make sure the "mode" pointers point to the up-to-date things, if - * they've changed. - */ - if (strcmp(meteringModeName_.c_str(), status_.meteringMode)) { - auto it = config_.meteringModes.find(meteringModeName_); - if (it == config_.meteringModes.end()) - LOG(RPiAgc, Fatal) << "No metering mode " << meteringModeName_; - meteringMode_ = &it->second; - copyString(meteringModeName_, status_.meteringMode, - sizeof(status_.meteringMode)); - } - if (strcmp(exposureModeName_.c_str(), status_.exposureMode)) { - auto it = config_.exposureModes.find(exposureModeName_); - if (it == config_.exposureModes.end()) - LOG(RPiAgc, Fatal) << "No exposure profile " << exposureModeName_; - exposureMode_ = &it->second; - copyString(exposureModeName_, status_.exposureMode, - sizeof(status_.exposureMode)); - } - if (strcmp(constraintModeName_.c_str(), status_.constraintMode)) { - auto it = - config_.constraintModes.find(constraintModeName_); - if (it == config_.constraintModes.end()) - LOG(RPiAgc, Fatal) << "No constraint list " << constraintModeName_; - constraintMode_ = &it->second; - copyString(constraintModeName_, status_.constraintMode, - sizeof(status_.constraintMode)); - } - LOG(RPiAgc, Debug) << "exposureMode " - << exposureModeName_ << " constraintMode " - << constraintModeName_ << " meteringMode " - << meteringModeName_; -} - -void Agc::fetchCurrentExposure(Metadata *imageMetadata) -{ - std::unique_lock<Metadata> lock(*imageMetadata); - DeviceStatus *deviceStatus = - imageMetadata->getLocked<DeviceStatus>("device.status"); - if (!deviceStatus) - LOG(RPiAgc, Fatal) << "No device metadata"; - current_.shutter = deviceStatus->shutterSpeed; - current_.analogueGain = deviceStatus->analogueGain; - AgcStatus *agcStatus = - imageMetadata->getLocked<AgcStatus>("agc.status"); - current_.totalExposure = agcStatus ? agcStatus->totalExposureValue : 0s; - current_.totalExposureNoDG = current_.shutter * current_.analogueGain; -} - -void Agc::fetchAwbStatus(Metadata *imageMetadata) -{ - awb_.gainR = 1.0; /* in case not found in metadata */ - awb_.gainG = 1.0; - awb_.gainB = 1.0; - if (imageMetadata->get("awb.status", awb_) != 0) - LOG(RPiAgc, Debug) << "No AWB status found"; -} - -static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, - std::vector<double> &weights, double gain) -{ - constexpr uint64_t maxVal = 1 << Statistics::NormalisationFactorPow2; - - ASSERT(weights.size() == stats->agcRegions.numRegions()); - - /* - * Note how the calculation below means that equal weights give you - * "average" metering (i.e. all pixels equally important). - */ - double rSum = 0, gSum = 0, bSum = 0, pixelSum = 0; - for (unsigned int i = 0; i < stats->agcRegions.numRegions(); i++) { - auto ®ion = stats->agcRegions.get(i); - double rAcc = std::min<double>(region.val.rSum * gain, (maxVal - 1) * region.counted); - double gAcc = std::min<double>(region.val.gSum * gain, (maxVal - 1) * region.counted); - double bAcc = std::min<double>(region.val.bSum * gain, (maxVal - 1) * region.counted); - rSum += rAcc * weights[i]; - gSum += gAcc * weights[i]; - bSum += bAcc * weights[i]; - pixelSum += region.counted * weights[i]; - } - if (pixelSum == 0.0) { - LOG(RPiAgc, Warning) << "computeInitialY: pixelSum is zero"; - return 0; - } - double ySum = rSum * awb.gainR * .299 + - gSum * awb.gainG * .587 + - bSum * awb.gainB * .114; - return ySum / pixelSum / maxVal; -} - -/* - * We handle extra gain through EV by adjusting our Y targets. However, you - * simply can't monitor histograms once they get very close to (or beyond!) - * saturation, so we clamp the Y targets to this value. It does mean that EV - * increases don't necessarily do quite what you might expect in certain - * (contrived) cases. - */ - -static constexpr double EvGainYTargetLimit = 0.9; - -static double constraintComputeGain(AgcConstraint &c, const Histogram &h, double lux, - double evGain, double &targetY) -{ - targetY = c.yTarget.eval(c.yTarget.domain().clip(lux)); - targetY = std::min(EvGainYTargetLimit, targetY * evGain); - double iqm = h.interQuantileMean(c.qLo, c.qHi); - return (targetY * h.bins()) / iqm; -} - -void Agc::computeGain(StatisticsPtr &statistics, Metadata *imageMetadata, - double &gain, double &targetY) -{ - struct LuxStatus lux = {}; - lux.lux = 400; /* default lux level to 400 in case no metadata found */ - if (imageMetadata->get("lux.status", lux) != 0) - LOG(RPiAgc, Warning) << "No lux level found"; - const Histogram &h = statistics->yHist; - double evGain = status_.ev * config_.baseEv; - /* - * The initial gain and target_Y come from some of the regions. After - * that we consider the histogram constraints. - */ - targetY = config_.yTarget.eval(config_.yTarget.domain().clip(lux.lux)); - targetY = std::min(EvGainYTargetLimit, targetY * evGain); - - /* - * Do this calculation a few times as brightness increase can be - * non-linear when there are saturated regions. - */ - gain = 1.0; - for (int i = 0; i < 8; i++) { - double initialY = computeInitialY(statistics, awb_, meteringMode_->weights, gain); - double extraGain = std::min(10.0, targetY / (initialY + .001)); - gain *= extraGain; - LOG(RPiAgc, Debug) << "Initial Y " << initialY << " target " << targetY - << " gives gain " << gain; - if (extraGain < 1.01) /* close enough */ - break; - } - - for (auto &c : *constraintMode_) { - double newTargetY; - double newGain = constraintComputeGain(c, h, lux.lux, evGain, newTargetY); - LOG(RPiAgc, Debug) << "Constraint has target_Y " - << newTargetY << " giving gain " << newGain; - if (c.bound == AgcConstraint::Bound::LOWER && newGain > gain) { - LOG(RPiAgc, Debug) << "Lower bound constraint adopted"; - gain = newGain; - targetY = newTargetY; - } else if (c.bound == AgcConstraint::Bound::UPPER && newGain < gain) { - LOG(RPiAgc, Debug) << "Upper bound constraint adopted"; - gain = newGain; - targetY = newTargetY; - } - } - LOG(RPiAgc, Debug) << "Final gain " << gain << " (target_Y " << targetY << " ev " - << status_.ev << " base_ev " << config_.baseEv - << ")"; -} - -void Agc::computeTargetExposure(double gain) -{ - if (status_.fixedShutter && status_.fixedAnalogueGain) { - /* - * When ag and shutter are both fixed, we need to drive the - * total exposure so that we end up with a digital gain of at least - * 1/minColourGain. Otherwise we'd desaturate channels causing - * white to go cyan or magenta. - */ - double minColourGain = std::min({ awb_.gainR, awb_.gainG, awb_.gainB, 1.0 }); - ASSERT(minColourGain != 0.0); - target_.totalExposure = - status_.fixedShutter * status_.fixedAnalogueGain / minColourGain; - } else { - /* - * The statistics reflect the image without digital gain, so the final - * total exposure we're aiming for is: - */ - target_.totalExposure = current_.totalExposureNoDG * gain; - /* The final target exposure is also limited to what the exposure mode allows. */ - Duration maxShutter = status_.fixedShutter - ? status_.fixedShutter - : exposureMode_->shutter.back(); - maxShutter = limitShutter(maxShutter); - Duration maxTotalExposure = - maxShutter * - (status_.fixedAnalogueGain != 0.0 - ? status_.fixedAnalogueGain - : exposureMode_->gain.back()); - target_.totalExposure = std::min(target_.totalExposure, maxTotalExposure); - } - LOG(RPiAgc, Debug) << "Target totalExposure " << target_.totalExposure; -} - -bool Agc::applyDigitalGain(double gain, double targetY) -{ - double minColourGain = std::min({ awb_.gainR, awb_.gainG, awb_.gainB, 1.0 }); - ASSERT(minColourGain != 0.0); - double dg = 1.0 / minColourGain; - /* - * I think this pipeline subtracts black level and rescales before we - * get the stats, so no need to worry about it. - */ - LOG(RPiAgc, Debug) << "after AWB, target dg " << dg << " gain " << gain - << " target_Y " << targetY; - /* - * Finally, if we're trying to reduce exposure but the target_Y is - * "close" to 1.0, then the gain computed for that constraint will be - * only slightly less than one, because the measured Y can never be - * larger than 1.0. When this happens, demand a large digital gain so - * that the exposure can be reduced, de-saturating the image much more - * quickly (and we then approach the correct value more quickly from - * below). - */ - bool desaturate = targetY > config_.fastReduceThreshold && - gain < sqrt(targetY); - if (desaturate) - dg /= config_.fastReduceThreshold; - LOG(RPiAgc, Debug) << "Digital gain " << dg << " desaturate? " << desaturate; - target_.totalExposureNoDG = target_.totalExposure / dg; - LOG(RPiAgc, Debug) << "Target totalExposureNoDG " << target_.totalExposureNoDG; - return desaturate; -} - -void Agc::filterExposure(bool desaturate) -{ - double speed = config_.speed; - /* - * AGC adapts instantly if both shutter and gain are directly specified - * or we're in the startup phase. - */ - if ((status_.fixedShutter && status_.fixedAnalogueGain) || - frameCount_ <= config_.startupFrames) - speed = 1.0; - if (!filtered_.totalExposure) { - filtered_.totalExposure = target_.totalExposure; - filtered_.totalExposureNoDG = target_.totalExposureNoDG; - } else { - /* - * If close to the result go faster, to save making so many - * micro-adjustments on the way. (Make this customisable?) - */ - if (filtered_.totalExposure < 1.2 * target_.totalExposure && - filtered_.totalExposure > 0.8 * target_.totalExposure) - speed = sqrt(speed); - filtered_.totalExposure = speed * target_.totalExposure + - filtered_.totalExposure * (1.0 - speed); - /* - * When desaturing, take a big jump down in totalExposureNoDG, - * which we'll hide with digital gain. - */ - if (desaturate) - filtered_.totalExposureNoDG = - target_.totalExposureNoDG; - else - filtered_.totalExposureNoDG = - speed * target_.totalExposureNoDG + - filtered_.totalExposureNoDG * (1.0 - speed); - } - /* - * We can't let the totalExposureNoDG exposure deviate too far below the - * total exposure, as there might not be enough digital gain available - * in the ISP to hide it (which will cause nasty oscillation). - */ - if (filtered_.totalExposureNoDG < - filtered_.totalExposure * config_.fastReduceThreshold) - filtered_.totalExposureNoDG = filtered_.totalExposure * config_.fastReduceThreshold; - LOG(RPiAgc, Debug) << "After filtering, totalExposure " << filtered_.totalExposure - << " no dg " << filtered_.totalExposureNoDG; -} - -void Agc::divideUpExposure() -{ - /* - * Sending the fixed shutter/gain cases through the same code may seem - * unnecessary, but it will make more sense when extend this to cover - * variable aperture. - */ - Duration exposureValue = filtered_.totalExposureNoDG; - Duration shutterTime; - double analogueGain; - shutterTime = status_.fixedShutter ? status_.fixedShutter - : exposureMode_->shutter[0]; - shutterTime = limitShutter(shutterTime); - analogueGain = status_.fixedAnalogueGain != 0.0 ? status_.fixedAnalogueGain - : exposureMode_->gain[0]; - analogueGain = limitGain(analogueGain); - if (shutterTime * analogueGain < exposureValue) { - for (unsigned int stage = 1; - stage < exposureMode_->gain.size(); stage++) { - if (!status_.fixedShutter) { - Duration stageShutter = - limitShutter(exposureMode_->shutter[stage]); - if (stageShutter * analogueGain >= exposureValue) { - shutterTime = exposureValue / analogueGain; - break; - } - shutterTime = stageShutter; - } - if (status_.fixedAnalogueGain == 0.0) { - if (exposureMode_->gain[stage] * shutterTime >= exposureValue) { - analogueGain = exposureValue / shutterTime; - break; - } - analogueGain = exposureMode_->gain[stage]; - analogueGain = limitGain(analogueGain); - } - } - } - LOG(RPiAgc, Debug) << "Divided up shutter and gain are " << shutterTime << " and " - << analogueGain; - /* - * Finally adjust shutter time for flicker avoidance (require both - * shutter and gain not to be fixed). - */ - if (!status_.fixedShutter && !status_.fixedAnalogueGain && - status_.flickerPeriod) { - int flickerPeriods = shutterTime / status_.flickerPeriod; - if (flickerPeriods) { - Duration newShutterTime = flickerPeriods * status_.flickerPeriod; - analogueGain *= shutterTime / newShutterTime; - /* - * We should still not allow the ag to go over the - * largest value in the exposure mode. Note that this - * may force more of the total exposure into the digital - * gain as a side-effect. - */ - analogueGain = std::min(analogueGain, exposureMode_->gain.back()); - analogueGain = limitGain(analogueGain); - shutterTime = newShutterTime; - } - LOG(RPiAgc, Debug) << "After flicker avoidance, shutter " - << shutterTime << " gain " << analogueGain; - } - filtered_.shutter = shutterTime; - filtered_.analogueGain = analogueGain; -} - -void Agc::writeAndFinish(Metadata *imageMetadata, bool desaturate) -{ - status_.totalExposureValue = filtered_.totalExposure; - status_.targetExposureValue = desaturate ? 0s : target_.totalExposureNoDG; - status_.shutterTime = filtered_.shutter; - status_.analogueGain = filtered_.analogueGain; - /* - * Write to metadata as well, in case anyone wants to update the camera - * immediately. - */ - imageMetadata->set("agc.status", status_); - LOG(RPiAgc, Debug) << "Output written, total exposure requested is " - << filtered_.totalExposure; - LOG(RPiAgc, Debug) << "Camera exposure update: shutter time " << filtered_.shutter - << " analogue gain " << filtered_.analogueGain; -} - -Duration Agc::limitShutter(Duration shutter) -{ - /* - * shutter == 0 is a special case for fixed shutter values, and must pass - * through unchanged - */ - if (!shutter) - return shutter; - - shutter = std::clamp(shutter, mode_.minShutter, maxShutter_); - return shutter; -} - -double Agc::limitGain(double gain) const -{ - /* - * Only limit the lower bounds of the gain value to what the sensor limits. - * The upper bound on analogue gain will be made up with additional digital - * gain applied by the ISP. - * - * gain == 0.0 is a special case for fixed shutter values, and must pass - * through unchanged - */ - if (!gain) - return gain; - - gain = std::max(gain, mode_.minAnalogueGain); - return gain; -} - -/* Register algorithm with the system. */ -static Algorithm *create(Controller *controller) -{ - return (Algorithm *)new Agc(controller); -} -static RegisterAlgorithm reg(NAME, &create); |