diff --git a/src/ipa/rpi/common/ipa_base.cpp b/src/ipa/rpi/common/ipa_base.cpp index a47ae3a9..f7e7ad5e 100644 --- a/src/ipa/rpi/common/ipa_base.cpp +++ b/src/ipa/rpi/common/ipa_base.cpp @@ -699,9 +699,9 @@ void IpaBase::applyControls(const ControlList &controls) } if (ctrl.second.get() == false) - agc->disableAuto(); + agc->disableAuto(0); else - agc->enableAuto(); + agc->enableAuto(0); libcameraMetadata_.set(controls::AeEnable, ctrl.second.get()); break; @@ -717,7 +717,7 @@ void IpaBase::applyControls(const ControlList &controls) } /* The control provides units of microseconds. */ - agc->setFixedShutter(ctrl.second.get() * 1.0us); + agc->setFixedShutter(0, ctrl.second.get() * 1.0us); libcameraMetadata_.set(controls::ExposureTime, ctrl.second.get()); break; @@ -732,7 +732,7 @@ void IpaBase::applyControls(const ControlList &controls) break; } - agc->setFixedAnalogueGain(ctrl.second.get()); + agc->setFixedAnalogueGain(0, ctrl.second.get()); libcameraMetadata_.set(controls::AnalogueGain, ctrl.second.get()); @@ -770,7 +770,7 @@ void IpaBase::applyControls(const ControlList &controls) int32_t idx = ctrl.second.get(); if (ConstraintModeTable.count(idx)) { - agc->setConstraintMode(ConstraintModeTable.at(idx)); + agc->setConstraintMode(0, ConstraintModeTable.at(idx)); libcameraMetadata_.set(controls::AeConstraintMode, idx); } else { LOG(IPARPI, Error) << "Constraint mode " << idx @@ -790,7 +790,7 @@ void IpaBase::applyControls(const ControlList &controls) int32_t idx = ctrl.second.get(); if (ExposureModeTable.count(idx)) { - agc->setExposureMode(ExposureModeTable.at(idx)); + agc->setExposureMode(0, ExposureModeTable.at(idx)); libcameraMetadata_.set(controls::AeExposureMode, idx); } else { LOG(IPARPI, Error) << "Exposure mode " << idx @@ -813,7 +813,7 @@ void IpaBase::applyControls(const ControlList &controls) * So convert to 2^EV */ double ev = pow(2.0, ctrl.second.get()); - agc->setEv(ev); + agc->setEv(0, ev); libcameraMetadata_.set(controls::ExposureValue, ctrl.second.get()); break; @@ -833,12 +833,12 @@ void IpaBase::applyControls(const ControlList &controls) switch (mode) { case controls::FlickerOff: - agc->setFlickerPeriod(0us); + agc->setFlickerPeriod(0, 0us); break; case controls::FlickerManual: - agc->setFlickerPeriod(flickerState_.manualPeriod); + agc->setFlickerPeriod(0, flickerState_.manualPeriod); break; @@ -872,7 +872,7 @@ void IpaBase::applyControls(const ControlList &controls) * first, and the period updated after, or vice versa. */ if (flickerState_.mode == controls::FlickerManual) - agc->setFlickerPeriod(flickerState_.manualPeriod); + agc->setFlickerPeriod(0, flickerState_.manualPeriod); break; } diff --git a/src/ipa/rpi/controller/agc_algorithm.h b/src/ipa/rpi/controller/agc_algorithm.h index b6949daa..b8986560 100644 --- a/src/ipa/rpi/controller/agc_algorithm.h +++ b/src/ipa/rpi/controller/agc_algorithm.h @@ -21,16 +21,19 @@ public: /* An AGC algorithm must provide the following: */ virtual unsigned int getConvergenceFrames() const = 0; virtual std::vector const &getWeights() const = 0; - virtual void setEv(double ev) = 0; - virtual void setFlickerPeriod(libcamera::utils::Duration flickerPeriod) = 0; - virtual void setFixedShutter(libcamera::utils::Duration fixedShutter) = 0; + virtual void setEv(unsigned int channel, double ev) = 0; + virtual void setFlickerPeriod(unsigned int channel, + libcamera::utils::Duration flickerPeriod) = 0; + virtual void setFixedShutter(unsigned int channel, + libcamera::utils::Duration fixedShutter) = 0; virtual void setMaxShutter(libcamera::utils::Duration maxShutter) = 0; - virtual void setFixedAnalogueGain(double fixedAnalogueGain) = 0; + virtual void setFixedAnalogueGain(unsigned int channel, double fixedAnalogueGain) = 0; virtual void setMeteringMode(std::string const &meteringModeName) = 0; - virtual void setExposureMode(std::string const &exposureModeName) = 0; - virtual void setConstraintMode(std::string const &contraintModeName) = 0; - virtual void enableAuto() = 0; - virtual void disableAuto() = 0; + virtual void setExposureMode(unsigned int channel, std::string const &exposureModeName) = 0; + virtual void setConstraintMode(unsigned int channel, std::string const &contraintModeName) = 0; + virtual void enableAuto(unsigned int channel) = 0; + virtual void disableAuto(unsigned int channel) = 0; + virtual void setActiveChannels(const std::vector &activeChannels) = 0; }; } /* namespace RPiController */ diff --git a/src/ipa/rpi/controller/meson.build b/src/ipa/rpi/controller/meson.build index feb0334e..20b9cda9 100644 --- a/src/ipa/rpi/controller/meson.build +++ b/src/ipa/rpi/controller/meson.build @@ -8,6 +8,7 @@ rpi_ipa_controller_sources = files([ 'pwl.cpp', 'rpi/af.cpp', 'rpi/agc.cpp', + 'rpi/agc_channel.cpp', 'rpi/alsc.cpp', 'rpi/awb.cpp', 'rpi/black_level.cpp', diff --git a/src/ipa/rpi/controller/rpi/agc.cpp b/src/ipa/rpi/controller/rpi/agc.cpp index 7b02972a..598fc890 100644 --- a/src/ipa/rpi/controller/rpi/agc.cpp +++ b/src/ipa/rpi/controller/rpi/agc.cpp @@ -5,20 +5,12 @@ * agc.cpp - AGC/AEC control algorithm */ -#include -#include -#include +#include "agc.h" #include -#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; @@ -28,881 +20,205 @@ LOG_DEFINE_CATEGORY(RPiAgc) #define NAME "rpi.agc" -int AgcMeteringMode::read(const libcamera::YamlObject ¶ms) +Agc::Agc(Controller *controller) + : AgcAlgorithm(controller), + activeChannels_({ 0 }) { - const YamlObject &yamlWeights = params["weights"]; - - for (const auto &p : yamlWeights.asList()) { - auto value = p.get(); - if (!value) - return -EINVAL; - weights.push_back(*value); - } - - return 0; } -static std::tuple -readMeteringModes(std::map &metering_modes, - const libcamera::YamlObject ¶ms) +char const *Agc::name() const { - 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 }; + return NAME; } -int AgcExposureMode::read(const libcamera::YamlObject ¶ms) +int Agc::read(const libcamera::YamlObject ¶ms) { - auto value = params["shutter"].getList(); - if (!value) - return -EINVAL; - std::transform(value->begin(), value->end(), std::back_inserter(shutter), - [](double v) { return v * 1us; }); - - value = params["gain"].getList(); - 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; + /* + * When there is only a single channel we can read the old style syntax. + * Otherwise we expect a "channels" keyword followed by a list of configurations. + */ + if (!params.contains("channels")) { + LOG(RPiAgc, Debug) << "Single channel only"; + channelData_.emplace_back(); + return channelData_.back().channel.read(params, getHardwareConfig()); } - return 0; -} - -static std::tuple -readExposureModes(std::map &exposureModes, - const libcamera::YamlObject ¶ms) -{ - std::string first; - int ret; - - for (const auto &[key, value] : params.asDict()) { - AgcExposureMode exposureMode; - ret = exposureMode.read(value); + const auto &channels = params["channels"].asList(); + for (auto ch = channels.begin(); ch != channels.end(); ch++) { + LOG(RPiAgc, Debug) << "Read AGC channel"; + channelData_.emplace_back(); + int ret = channelData_.back().channel.read(*ch, getHardwareConfig()); if (ret) - return { ret, {} }; - - exposureModes[key] = std::move(exposureMode); - if (first.empty()) - first = key; + return ret; } - return { 0, first }; -} - -int AgcConstraint::read(const libcamera::YamlObject ¶ms) -{ - std::string boundString = params["bound"].get(""); - 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; + LOG(RPiAgc, Debug) << "Read " << channelData_.size() << " channel(s)"; + if (channelData_.empty()) { + LOG(RPiAgc, Error) << "No AGC channels provided"; + return -1; } - bound = boundString == "UPPER" ? Bound::UPPER : Bound::LOWER; - - auto value = params["q_lo"].get(); - if (!value) - return -EINVAL; - qLo = *value; - - value = params["q_hi"].get(); - if (!value) - return -EINVAL; - qHi = *value; - - return yTarget.read(params["y_target"]); -} -static std::tuple -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 }; + return 0; } -static std::tuple -readConstraintModes(std::map &constraintModes, - const libcamera::YamlObject ¶ms) +int Agc::checkChannel(unsigned int channelIndex) const { - 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; + if (channelIndex >= channelData_.size()) { + LOG(RPiAgc, Warning) << "AGC channel " << channelIndex << " not available"; + return -1; } - 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(0.2); - startupFrames = params["startup_frames"].get(10); - convergenceFrames = params["convergence_frames"].get(6); - fastReduceThreshold = params["fast_reduce_threshold"].get(0.4); - baseEv = params["base_ev"].get(1.0); - - /* Start with quite a low value as ramping up is easier than ramping down. */ - defaultExposureTime = params["default_exposure_time"].get(1000) * 1us; - defaultAnalogueGain = params["default_analogue_gain"].get(1.0); - return 0; } -Agc::ExposureValues::ExposureValues() - : shutter(0s), analogueGain(0), - totalExposure(0s), totalExposureNoDG(0s) +void Agc::disableAuto(unsigned int channelIndex) { -} - -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). - */ - status_ = {}; - status_.ev = ev_; -} + if (checkChannel(channelIndex)) + return; -char const *Agc::name() const -{ - return NAME; + LOG(RPiAgc, Debug) << "disableAuto for channel " << channelIndex; + channelData_[channelIndex].channel.disableAuto(); } -int Agc::read(const libcamera::YamlObject ¶ms) +void Agc::enableAuto(unsigned int channelIndex) { - 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; - } - } + if (checkChannel(channelIndex)) + return; - /* - * 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; + LOG(RPiAgc, Debug) << "enableAuto for channel " << channelIndex; + channelData_[channelIndex].channel.enableAuto(); } 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; + /* If there are n channels, it presumably takes n times as long to converge. */ + return channelData_[0].channel.getConvergenceFrames() * activeChannels_.size(); } std::vector const &Agc::getWeights() const { /* - * In case someone calls setMeteringMode and then this before the - * algorithm has run and updated the meteringMode_ pointer. + * In future the metering weights may be determined differently, making it + * difficult to associate different sets of weight with different channels. + * Therefore we shall impose a limitation, at least for now, that all + * channels will use the same weights. */ - auto it = config_.meteringModes.find(meteringModeName_); - if (it == config_.meteringModes.end()) - return meteringMode_->weights; - return it->second.weights; + return channelData_[0].channel.getWeights(); } -void Agc::setEv(double ev) +void Agc::setEv(unsigned int channelIndex, double ev) { - ev_ = ev; -} + if (checkChannel(channelIndex)) + return; -void Agc::setFlickerPeriod(Duration flickerPeriod) -{ - flickerPeriod_ = flickerPeriod; + LOG(RPiAgc, Debug) << "setEv " << ev << " for channel " << channelIndex; + channelData_[channelIndex].channel.setEv(ev); } -void Agc::setMaxShutter(Duration maxShutter) +void Agc::setFlickerPeriod(unsigned int channelIndex, Duration flickerPeriod) { - maxShutter_ = maxShutter; -} + if (checkChannel(channelIndex)) + return; -void Agc::setFixedShutter(Duration fixedShutter) -{ - fixedShutter_ = fixedShutter; - /* Set this in case someone calls disableAuto() straight after. */ - status_.shutterTime = limitShutter(fixedShutter_); + LOG(RPiAgc, Debug) << "setFlickerPeriod " << flickerPeriod + << " for channel " << channelIndex; + channelData_[channelIndex].channel.setFlickerPeriod(flickerPeriod); } -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) +void Agc::setMaxShutter(Duration maxShutter) { - /* 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); + /* Frame durations will be the same across all channels too. */ + for (auto &data : channelData_) + data.channel.setMaxShutter(maxShutter); } -void Agc::prepare(Metadata *imageMetadata) +void Agc::setFixedShutter(unsigned int channelIndex, Duration fixedShutter) { - Duration totalExposureValue = status_.totalExposureValue; - AgcStatus delayedStatus; - AgcPrepareStatus prepareStatus; - - if (!imageMetadata->get("agc.delayed_status", delayedStatus)) - totalExposureValue = delayedStatus.totalExposureValue; - - prepareStatus.digitalGain = 1.0; - prepareStatus.locked = false; - - 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) { - double 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? - */ - prepareStatus.digitalGain = std::max(1.0, std::min(digitalGain, 4.0)); - LOG(RPiAgc, Debug) << "Actual exposure " << actualExposure; - LOG(RPiAgc, Debug) << "Use digitalGain " << prepareStatus.digitalGain; - LOG(RPiAgc, Debug) << "Effective exposure " - << actualExposure * prepareStatus.digitalGain; - /* Decide whether AEC/AGC has converged. */ - prepareStatus.locked = updateLockStatus(deviceStatus); - } - } else - LOG(RPiAgc, Warning) << name() << ": no device metadata"; - imageMetadata->set("agc.prepare_status", prepareStatus); - } -} + if (checkChannel(channelIndex)) + return; -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(); - /* Fetch the AWB status immediately, so that we can assume it's there. */ - fetchAwbStatus(imageMetadata); - /* 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); - /* The results have to be filtered so as not to change too rapidly. */ - filterExposure(); - /* - * 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 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); + LOG(RPiAgc, Debug) << "setFixedShutter " << fixedShutter + << " for channel " << channelIndex; + channelData_[channelIndex].channel.setFixedShutter(fixedShutter); } -bool Agc::updateLockStatus(DeviceStatus const &deviceStatus) +void Agc::setFixedAnalogueGain(unsigned int channelIndex, double fixedAnalogueGain) { - 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; + if (checkChannel(channelIndex)) + return; - /* 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_; - return lockCount_ == maxLockCount; + LOG(RPiAgc, Debug) << "setFixedAnalogueGain " << fixedAnalogueGain + << " for channel " << channelIndex; + channelData_[channelIndex].channel.setFixedAnalogueGain(fixedAnalogueGain); } -void Agc::housekeepConfig() +void Agc::setMeteringMode(std::string const &meteringModeName) { - /* 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 (meteringModeName_ != status_.meteringMode) { - auto it = config_.meteringModes.find(meteringModeName_); - if (it == config_.meteringModes.end()) { - LOG(RPiAgc, Warning) << "No metering mode " << meteringModeName_; - meteringModeName_ = status_.meteringMode; - } else { - meteringMode_ = &it->second; - status_.meteringMode = meteringModeName_; - } - } - if (exposureModeName_ != status_.exposureMode) { - auto it = config_.exposureModes.find(exposureModeName_); - if (it == config_.exposureModes.end()) { - LOG(RPiAgc, Warning) << "No exposure profile " << exposureModeName_; - exposureModeName_ = status_.exposureMode; - } else { - exposureMode_ = &it->second; - status_.exposureMode = exposureModeName_; - } - } - if (constraintModeName_ != status_.constraintMode) { - auto it = config_.constraintModes.find(constraintModeName_); - if (it == config_.constraintModes.end()) { - LOG(RPiAgc, Warning) << "No constraint list " << constraintModeName_; - constraintModeName_ = status_.constraintMode; - } else { - constraintMode_ = &it->second; - status_.constraintMode = constraintModeName_; - } - } - LOG(RPiAgc, Debug) << "exposureMode " - << exposureModeName_ << " constraintMode " - << constraintModeName_ << " meteringMode " - << meteringModeName_; + /* Metering modes will be the same across all channels too. */ + for (auto &data : channelData_) + data.channel.setMeteringMode(meteringModeName); } -void Agc::fetchCurrentExposure(Metadata *imageMetadata) +void Agc::setExposureMode(unsigned int channelIndex, std::string const &exposureModeName) { - std::unique_lock lock(*imageMetadata); - DeviceStatus *deviceStatus = - imageMetadata->getLocked("device.status"); - if (!deviceStatus) - LOG(RPiAgc, Fatal) << "No device metadata"; - current_.shutter = deviceStatus->shutterSpeed; - current_.analogueGain = deviceStatus->analogueGain; - AgcStatus *agcStatus = - imageMetadata->getLocked("agc.status"); - current_.totalExposure = agcStatus ? agcStatus->totalExposureValue : 0s; - current_.totalExposureNoDG = current_.shutter * current_.analogueGain; -} + if (checkChannel(channelIndex)) + return; -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"; + LOG(RPiAgc, Debug) << "setExposureMode " << exposureModeName + << " for channel " << channelIndex; + channelData_[channelIndex].channel.setExposureMode(exposureModeName); } -static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, - std::vector &weights, double gain) +void Agc::setConstraintMode(unsigned int channelIndex, std::string const &constraintModeName) { - constexpr uint64_t maxVal = 1 << Statistics::NormalisationFactorPow2; + if (checkChannel(channelIndex)) + return; - ASSERT(weights.size() == stats->agcRegions.numRegions()); - - /* - * Note that the weights are applied by the IPA to the statistics directly, - * before they are given to us here. - */ - 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); - rSum += std::min(region.val.rSum * gain, (maxVal - 1) * region.counted); - gSum += std::min(region.val.gSum * gain, (maxVal - 1) * region.counted); - bSum += std::min(region.val.bSum * gain, (maxVal - 1) * region.counted); - pixelSum += region.counted; - } - 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; + channelData_[channelIndex].channel.setConstraintMode(constraintModeName); } -/* - * 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) +template +std::ostream &operator<<(std::ostream &os, const std::vector &v) { - 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; + os << "{"; + for (const auto &e : v) + os << " " << e; + os << " }"; + return os; } -void Agc::computeGain(StatisticsPtr &statistics, Metadata *imageMetadata, - double &gain, double &targetY) +void Agc::setActiveChannels(const std::vector &activeChannels) { - 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; - } + if (activeChannels.empty()) { + LOG(RPiAgc, Warning) << "No active AGC channels supplied"; + return; } - 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; - filtered_.totalExposureNoDG = filtered_.totalExposure / dg; - LOG(RPiAgc, Debug) << "Target totalExposureNoDG " << filtered_.totalExposureNoDG; - return desaturate; -} - -void Agc::filterExposure() -{ - 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; - } 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); - } - LOG(RPiAgc, Debug) << "After filtering, totalExposure " << filtered_.totalExposure - << " no dg " << filtered_.totalExposureNoDG; -} + for (auto index : activeChannels) + if (checkChannel(index)) + return; -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; + LOG(RPiAgc, Debug) << "setActiveChannels " << activeChannels; + activeChannels_ = activeChannels; } -void Agc::writeAndFinish(Metadata *imageMetadata, bool desaturate) +void Agc::switchMode(CameraMode const &cameraMode, + Metadata *metadata) { - 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; + LOG(RPiAgc, Debug) << "switchMode for channel 0"; + channelData_[0].channel.switchMode(cameraMode, metadata); } -Duration Agc::limitShutter(Duration shutter) +void Agc::prepare(Metadata *imageMetadata) { - /* - * 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; + LOG(RPiAgc, Debug) << "prepare for channel 0"; + channelData_[0].channel.prepare(imageMetadata); } -double Agc::limitGain(double gain) const +void Agc::process(StatisticsPtr &stats, Metadata *imageMetadata) { - /* - * 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; + LOG(RPiAgc, Debug) << "process for channel 0"; + channelData_[0].channel.process(stats, imageMetadata); } /* Register algorithm with the system. */ diff --git a/src/ipa/rpi/controller/rpi/agc.h b/src/ipa/rpi/controller/rpi/agc.h index aaf77c8f..a476ea70 100644 --- a/src/ipa/rpi/controller/rpi/agc.h +++ b/src/ipa/rpi/controller/rpi/agc.h @@ -6,60 +6,17 @@ */ #pragma once +#include #include -#include - -#include #include "../agc_algorithm.h" -#include "../agc_status.h" -#include "../pwl.h" -/* This is our implementation of AGC. */ +#include "agc_channel.h" namespace RPiController { -struct AgcMeteringMode { - std::vector weights; - int read(const libcamera::YamlObject ¶ms); -}; - -struct AgcExposureMode { - std::vector shutter; - std::vector gain; - int read(const libcamera::YamlObject ¶ms); -}; - -struct AgcConstraint { - enum class Bound { LOWER = 0, UPPER = 1 }; - Bound bound; - double qLo; - double qHi; - Pwl yTarget; - int read(const libcamera::YamlObject ¶ms); -}; - -typedef std::vector AgcConstraintMode; - -struct AgcConfig { - int read(const libcamera::YamlObject ¶ms); - std::map meteringModes; - std::map exposureModes; - std::map constraintModes; - Pwl yTarget; - double speed; - uint16_t startupFrames; - unsigned int convergenceFrames; - double maxChange; - double minChange; - double fastReduceThreshold; - double speedUpThreshold; - std::string defaultMeteringMode; - std::string defaultExposureMode; - std::string defaultConstraintMode; - double baseEv; - libcamera::utils::Duration defaultExposureTime; - double defaultAnalogueGain; +struct AgcChannelData { + AgcChannel channel; }; class Agc : public AgcAlgorithm @@ -70,65 +27,30 @@ public: int read(const libcamera::YamlObject ¶ms) override; unsigned int getConvergenceFrames() const override; std::vector const &getWeights() const override; - void setEv(double ev) override; - void setFlickerPeriod(libcamera::utils::Duration flickerPeriod) override; + void setEv(unsigned int channel, double ev) override; + void setFlickerPeriod(unsigned int channelIndex, + libcamera::utils::Duration flickerPeriod) override; void setMaxShutter(libcamera::utils::Duration maxShutter) override; - void setFixedShutter(libcamera::utils::Duration fixedShutter) override; - void setFixedAnalogueGain(double fixedAnalogueGain) override; + void setFixedShutter(unsigned int channelIndex, + libcamera::utils::Duration fixedShutter) override; + void setFixedAnalogueGain(unsigned int channelIndex, + double fixedAnalogueGain) override; void setMeteringMode(std::string const &meteringModeName) override; - void setExposureMode(std::string const &exposureModeName) override; - void setConstraintMode(std::string const &contraintModeName) override; - void enableAuto() override; - void disableAuto() override; + void setExposureMode(unsigned int channelIndex, + std::string const &exposureModeName) override; + void setConstraintMode(unsigned int channelIndex, + std::string const &contraintModeName) override; + void enableAuto(unsigned int channelIndex) override; + void disableAuto(unsigned int channelIndex) override; void switchMode(CameraMode const &cameraMode, Metadata *metadata) override; void prepare(Metadata *imageMetadata) override; void process(StatisticsPtr &stats, Metadata *imageMetadata) override; + void setActiveChannels(const std::vector &activeChannels) override; private: - bool updateLockStatus(DeviceStatus const &deviceStatus); - AgcConfig config_; - void housekeepConfig(); - void fetchCurrentExposure(Metadata *imageMetadata); - void fetchAwbStatus(Metadata *imageMetadata); - void computeGain(StatisticsPtr &statistics, Metadata *imageMetadata, - double &gain, double &targetY); - void computeTargetExposure(double gain); - void filterExposure(); - bool applyDigitalGain(double gain, double targetY); - void divideUpExposure(); - void writeAndFinish(Metadata *imageMetadata, bool desaturate); - libcamera::utils::Duration limitShutter(libcamera::utils::Duration shutter); - double limitGain(double gain) const; - AgcMeteringMode *meteringMode_; - AgcExposureMode *exposureMode_; - AgcConstraintMode *constraintMode_; - CameraMode mode_; - uint64_t frameCount_; - AwbStatus awb_; - struct ExposureValues { - ExposureValues(); - - libcamera::utils::Duration shutter; - double analogueGain; - libcamera::utils::Duration totalExposure; - libcamera::utils::Duration totalExposureNoDG; /* without digital gain */ - }; - ExposureValues current_; /* values for the current frame */ - ExposureValues target_; /* calculate the values we want here */ - ExposureValues filtered_; /* these values are filtered towards target */ - AgcStatus status_; - int lockCount_; - DeviceStatus lastDeviceStatus_; - libcamera::utils::Duration lastTargetExposure_; - /* Below here the "settings" that applications can change. */ - std::string meteringModeName_; - std::string exposureModeName_; - std::string constraintModeName_; - double ev_; - libcamera::utils::Duration flickerPeriod_; - libcamera::utils::Duration maxShutter_; - libcamera::utils::Duration fixedShutter_; - double fixedAnalogueGain_; + int checkChannel(unsigned int channel) const; + std::vector channelData_; + std::vector activeChannels_; }; } /* namespace RPiController */ diff --git a/src/ipa/rpi/controller/rpi/agc_channel.cpp b/src/ipa/rpi/controller/rpi/agc_channel.cpp new file mode 100644 index 00000000..b9b03af5 --- /dev/null +++ b/src/ipa/rpi/controller/rpi/agc_channel.cpp @@ -0,0 +1,924 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ +/* + * Copyright (C) 2023, Raspberry Pi Ltd + * + * agc_channel.cpp - AGC/AEC control algorithm + */ + +#include "agc_channel.h" + +#include +#include + +#include + +#include "../awb_status.h" +#include "../device_status.h" +#include "../histogram.h" +#include "../lux_status.h" +#include "../metadata.h" + +using namespace RPiController; +using namespace libcamera; +using libcamera::utils::Duration; +using namespace std::literals::chrono_literals; + +LOG_DECLARE_CATEGORY(RPiAgc) + +int AgcMeteringMode::read(const libcamera::YamlObject ¶ms) +{ + const YamlObject &yamlWeights = params["weights"]; + + for (const auto &p : yamlWeights.asList()) { + auto value = p.get(); + if (!value) + return -EINVAL; + weights.push_back(*value); + } + + return 0; +} + +static std::tuple +readMeteringModes(std::map &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(); + if (!value) + return -EINVAL; + std::transform(value->begin(), value->end(), std::back_inserter(shutter), + [](double v) { return v * 1us; }); + + value = params["gain"].getList(); + 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 +readExposureModes(std::map &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(""); + 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(); + if (!value) + return -EINVAL; + qLo = *value; + + value = params["q_hi"].get(); + if (!value) + return -EINVAL; + qHi = *value; + + return yTarget.read(params["y_target"]); +} + +static std::tuple +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 +readConstraintModes(std::map &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(0.2); + startupFrames = params["startup_frames"].get(10); + convergenceFrames = params["convergence_frames"].get(6); + fastReduceThreshold = params["fast_reduce_threshold"].get(0.4); + baseEv = params["base_ev"].get(1.0); + + /* Start with quite a low value as ramping up is easier than ramping down. */ + defaultExposureTime = params["default_exposure_time"].get(1000) * 1us; + defaultAnalogueGain = params["default_analogue_gain"].get(1.0); + + return 0; +} + +AgcChannel::ExposureValues::ExposureValues() + : shutter(0s), analogueGain(0), + totalExposure(0s), totalExposureNoDG(0s) +{ +} + +AgcChannel::AgcChannel() + : 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). + */ + status_ = {}; + status_.ev = ev_; +} + +int AgcChannel::read(const libcamera::YamlObject ¶ms, + const Controller::HardwareConfig &hardwareConfig) +{ + int ret = config_.read(params); + if (ret) + return ret; + + const Size &size = hardwareConfig.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 AgcChannel::disableAuto() +{ + fixedShutter_ = status_.shutterTime; + fixedAnalogueGain_ = status_.analogueGain; +} + +void AgcChannel::enableAuto() +{ + fixedShutter_ = 0s; + fixedAnalogueGain_ = 0; +} + +unsigned int AgcChannel::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; +} + +std::vector const &AgcChannel::getWeights() const +{ + /* + * In case someone calls setMeteringMode and then this before the + * algorithm has run and updated the meteringMode_ pointer. + */ + auto it = config_.meteringModes.find(meteringModeName_); + if (it == config_.meteringModes.end()) + return meteringMode_->weights; + return it->second.weights; +} + +void AgcChannel::setEv(double ev) +{ + ev_ = ev; +} + +void AgcChannel::setFlickerPeriod(Duration flickerPeriod) +{ + flickerPeriod_ = flickerPeriod; +} + +void AgcChannel::setMaxShutter(Duration maxShutter) +{ + maxShutter_ = maxShutter; +} + +void AgcChannel::setFixedShutter(Duration fixedShutter) +{ + fixedShutter_ = fixedShutter; + /* Set this in case someone calls disableAuto() straight after. */ + status_.shutterTime = limitShutter(fixedShutter_); +} + +void AgcChannel::setFixedAnalogueGain(double fixedAnalogueGain) +{ + fixedAnalogueGain_ = fixedAnalogueGain; + /* Set this in case someone calls disableAuto() straight after. */ + status_.analogueGain = limitGain(fixedAnalogueGain); +} + +void AgcChannel::setMeteringMode(std::string const &meteringModeName) +{ + meteringModeName_ = meteringModeName; +} + +void AgcChannel::setExposureMode(std::string const &exposureModeName) +{ + exposureModeName_ = exposureModeName; +} + +void AgcChannel::setConstraintMode(std::string const &constraintModeName) +{ + constraintModeName_ = constraintModeName; +} + +void AgcChannel::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 AgcChannel::prepare(Metadata *imageMetadata) +{ + Duration totalExposureValue = status_.totalExposureValue; + AgcStatus delayedStatus; + AgcPrepareStatus prepareStatus; + + if (!imageMetadata->get("agc.delayed_status", delayedStatus)) + totalExposureValue = delayedStatus.totalExposureValue; + + prepareStatus.digitalGain = 1.0; + prepareStatus.locked = false; + + 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) { + double 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? + */ + prepareStatus.digitalGain = std::max(1.0, std::min(digitalGain, 4.0)); + LOG(RPiAgc, Debug) << "Actual exposure " << actualExposure; + LOG(RPiAgc, Debug) << "Use digitalGain " << prepareStatus.digitalGain; + LOG(RPiAgc, Debug) << "Effective exposure " + << actualExposure * prepareStatus.digitalGain; + /* Decide whether AEC/AGC has converged. */ + prepareStatus.locked = updateLockStatus(deviceStatus); + } + } else + LOG(RPiAgc, Warning) << "AgcChannel: no device metadata"; + imageMetadata->set("agc.prepare_status", prepareStatus); + } +} + +void AgcChannel::process(StatisticsPtr &stats, Metadata *imageMetadata) +{ + frameCount_++; + /* + * First a little bit of housekeeping, fetching up-to-date settings and + * configuration, that kind of thing. + */ + housekeepConfig(); + /* Fetch the AWB status immediately, so that we can assume it's there. */ + fetchAwbStatus(imageMetadata); + /* 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); + /* The results have to be filtered so as not to change too rapidly. */ + filterExposure(); + /* + * 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 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); +} + +bool AgcChannel::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_; + return lockCount_ == maxLockCount; +} + +void AgcChannel::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 (meteringModeName_ != status_.meteringMode) { + auto it = config_.meteringModes.find(meteringModeName_); + if (it == config_.meteringModes.end()) { + LOG(RPiAgc, Warning) << "No metering mode " << meteringModeName_; + meteringModeName_ = status_.meteringMode; + } else { + meteringMode_ = &it->second; + status_.meteringMode = meteringModeName_; + } + } + if (exposureModeName_ != status_.exposureMode) { + auto it = config_.exposureModes.find(exposureModeName_); + if (it == config_.exposureModes.end()) { + LOG(RPiAgc, Warning) << "No exposure profile " << exposureModeName_; + exposureModeName_ = status_.exposureMode; + } else { + exposureMode_ = &it->second; + status_.exposureMode = exposureModeName_; + } + } + if (constraintModeName_ != status_.constraintMode) { + auto it = config_.constraintModes.find(constraintModeName_); + if (it == config_.constraintModes.end()) { + LOG(RPiAgc, Warning) << "No constraint list " << constraintModeName_; + constraintModeName_ = status_.constraintMode; + } else { + constraintMode_ = &it->second; + status_.constraintMode = constraintModeName_; + } + } + LOG(RPiAgc, Debug) << "exposureMode " + << exposureModeName_ << " constraintMode " + << constraintModeName_ << " meteringMode " + << meteringModeName_; +} + +void AgcChannel::fetchCurrentExposure(Metadata *imageMetadata) +{ + std::unique_lock lock(*imageMetadata); + DeviceStatus *deviceStatus = + imageMetadata->getLocked("device.status"); + if (!deviceStatus) + LOG(RPiAgc, Fatal) << "No device metadata"; + current_.shutter = deviceStatus->shutterSpeed; + current_.analogueGain = deviceStatus->analogueGain; + AgcStatus *agcStatus = + imageMetadata->getLocked("agc.status"); + current_.totalExposure = agcStatus ? agcStatus->totalExposureValue : 0s; + current_.totalExposureNoDG = current_.shutter * current_.analogueGain; +} + +void AgcChannel::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 &weights, double gain) +{ + constexpr uint64_t maxVal = 1 << Statistics::NormalisationFactorPow2; + + /* + * If we have no AGC region stats, but do have a a Y histogram, use that + * directly to caluclate the mean Y value of the image. + */ + if (!stats->agcRegions.numRegions() && stats->yHist.bins()) { + /* + * When the gain is applied to the histogram, anything below minBin + * will scale up directly with the gain, but anything above that + * will saturate into the top bin. + */ + auto &hist = stats->yHist; + double minBin = std::min(1.0, 1.0 / gain) * hist.bins(); + double binMean = hist.interBinMean(0.0, minBin); + double numUnsaturated = hist.cumulativeFreq(minBin); + /* This term is from all the pixels that won't saturate. */ + double ySum = binMean * gain * numUnsaturated; + /* And add the ones that will saturate. */ + ySum += (hist.total() - numUnsaturated) * hist.bins(); + return ySum / hist.total() / hist.bins(); + } + + ASSERT(weights.size() == stats->agcRegions.numRegions()); + + /* + * Note that the weights are applied by the IPA to the statistics directly, + * before they are given to us here. + */ + 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); + rSum += std::min(region.val.rSum * gain, (maxVal - 1) * region.counted); + gSum += std::min(region.val.gSum * gain, (maxVal - 1) * region.counted); + bSum += std::min(region.val.bSum * gain, (maxVal - 1) * region.counted); + pixelSum += region.counted; + } + if (pixelSum == 0.0) { + LOG(RPiAgc, Warning) << "computeInitialY: pixelSum is zero"; + return 0; + } + + double ySum; + /* Factor in the AWB correction if needed. */ + if (stats->agcStatsPos == Statistics::AgcStatsPos::PreWb) { + ySum = rSum * awb.gainR * .299 + + gSum * awb.gainG * .587 + + gSum * awb.gainB * .114; + } else + ySum = rSum * .299 + gSum * .587 + gSum * .114; + + return ySum / pixelSum / (1 << 16); +} + +/* + * 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 AgcChannel::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 AgcChannel::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 AgcChannel::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; + filtered_.totalExposureNoDG = filtered_.totalExposure / dg; + LOG(RPiAgc, Debug) << "Target totalExposureNoDG " << filtered_.totalExposureNoDG; + return desaturate; +} + +void AgcChannel::filterExposure() +{ + 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; + } 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); + } + LOG(RPiAgc, Debug) << "After filtering, totalExposure " << filtered_.totalExposure + << " no dg " << filtered_.totalExposureNoDG; +} + +void AgcChannel::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 AgcChannel::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 AgcChannel::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 AgcChannel::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; +} diff --git a/src/ipa/rpi/controller/rpi/agc_channel.h b/src/ipa/rpi/controller/rpi/agc_channel.h new file mode 100644 index 00000000..aca79ef2 --- /dev/null +++ b/src/ipa/rpi/controller/rpi/agc_channel.h @@ -0,0 +1,137 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ +/* + * Copyright (C) 2023, Raspberry Pi Ltd + * + * agc_channel.h - AGC/AEC control algorithm + */ +#pragma once + +#include +#include +#include + +#include + +#include "../agc_status.h" +#include "../awb_status.h" +#include "../controller.h" +#include "../pwl.h" + +/* This is our implementation of AGC. */ + +namespace RPiController { + +struct AgcMeteringMode { + std::vector weights; + int read(const libcamera::YamlObject ¶ms); +}; + +struct AgcExposureMode { + std::vector shutter; + std::vector gain; + int read(const libcamera::YamlObject ¶ms); +}; + +struct AgcConstraint { + enum class Bound { LOWER = 0, + UPPER = 1 }; + Bound bound; + double qLo; + double qHi; + Pwl yTarget; + int read(const libcamera::YamlObject ¶ms); +}; + +typedef std::vector AgcConstraintMode; + +struct AgcConfig { + int read(const libcamera::YamlObject ¶ms); + std::map meteringModes; + std::map exposureModes; + std::map constraintModes; + Pwl yTarget; + double speed; + uint16_t startupFrames; + unsigned int convergenceFrames; + double maxChange; + double minChange; + double fastReduceThreshold; + double speedUpThreshold; + std::string defaultMeteringMode; + std::string defaultExposureMode; + std::string defaultConstraintMode; + double baseEv; + libcamera::utils::Duration defaultExposureTime; + double defaultAnalogueGain; +}; + +class AgcChannel +{ +public: + AgcChannel(); + int read(const libcamera::YamlObject ¶ms, + const Controller::HardwareConfig &hardwareConfig); + unsigned int getConvergenceFrames() const; + std::vector const &getWeights() const; + void setEv(double ev); + void setFlickerPeriod(libcamera::utils::Duration flickerPeriod); + void setMaxShutter(libcamera::utils::Duration maxShutter); + void setFixedShutter(libcamera::utils::Duration fixedShutter); + void setFixedAnalogueGain(double fixedAnalogueGain); + void setMeteringMode(std::string const &meteringModeName); + void setExposureMode(std::string const &exposureModeName); + void setConstraintMode(std::string const &contraintModeName); + void enableAuto(); + void disableAuto(); + void switchMode(CameraMode const &cameraMode, Metadata *metadata); + void prepare(Metadata *imageMetadata); + void process(StatisticsPtr &stats, Metadata *imageMetadata); + +private: + bool updateLockStatus(DeviceStatus const &deviceStatus); + AgcConfig config_; + void housekeepConfig(); + void fetchCurrentExposure(Metadata *imageMetadata); + void fetchAwbStatus(Metadata *imageMetadata); + void computeGain(StatisticsPtr &statistics, Metadata *imageMetadata, + double &gain, double &targetY); + void computeTargetExposure(double gain); + void filterExposure(); + bool applyDigitalGain(double gain, double targetY); + void divideUpExposure(); + void writeAndFinish(Metadata *imageMetadata, bool desaturate); + libcamera::utils::Duration limitShutter(libcamera::utils::Duration shutter); + double limitGain(double gain) const; + AgcMeteringMode *meteringMode_; + AgcExposureMode *exposureMode_; + AgcConstraintMode *constraintMode_; + CameraMode mode_; + uint64_t frameCount_; + AwbStatus awb_; + struct ExposureValues { + ExposureValues(); + + libcamera::utils::Duration shutter; + double analogueGain; + libcamera::utils::Duration totalExposure; + libcamera::utils::Duration totalExposureNoDG; /* without digital gain */ + }; + ExposureValues current_; /* values for the current frame */ + ExposureValues target_; /* calculate the values we want here */ + ExposureValues filtered_; /* these values are filtered towards target */ + AgcStatus status_; + int lockCount_; + DeviceStatus lastDeviceStatus_; + libcamera::utils::Duration lastTargetExposure_; + /* Below here the "settings" that applications can change. */ + std::string meteringModeName_; + std::string exposureModeName_; + std::string constraintModeName_; + double ev_; + libcamera::utils::Duration flickerPeriod_; + libcamera::utils::Duration maxShutter_; + libcamera::utils::Duration fixedShutter_; + double fixedAnalogueGain_; +}; + +} /* namespace RPiController */