diff options
Diffstat (limited to 'src/ipa/rkisp1/algorithms/agc.cpp')
| -rw-r--r-- | src/ipa/rkisp1/algorithms/agc.cpp | 424 |
1 files changed, 221 insertions, 203 deletions
diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp index 47a6f7b2..f12f8b60 100644 --- a/src/ipa/rkisp1/algorithms/agc.cpp +++ b/src/ipa/rkisp1/algorithms/agc.cpp @@ -2,7 +2,7 @@ /* * Copyright (C) 2021-2022, Ideas On Board * - * agc.cpp - AGC/AEC mean-based control algorithm + * AGC/AEC mean-based control algorithm */ #include "agc.h" @@ -10,6 +10,8 @@ #include <algorithm> #include <chrono> #include <cmath> +#include <tuple> +#include <vector> #include <libcamera/base/log.h> #include <libcamera/base/utils.h> @@ -17,6 +19,8 @@ #include <libcamera/control_ids.h> #include <libcamera/ipa/core_ipa_interface.h> +#include "libcamera/internal/yaml_parser.h" + #include "libipa/histogram.h" /** @@ -36,35 +40,121 @@ namespace ipa::rkisp1::algorithms { LOG_DEFINE_CATEGORY(RkISP1Agc) -/* Minimum limit for analogue gain value */ -static constexpr double kMinAnalogueGain = 1.0; +int Agc::parseMeteringModes(IPAContext &context, const YamlObject &tuningData) +{ + if (!tuningData.isDictionary()) + LOG(RkISP1Agc, Warning) + << "'AeMeteringMode' parameter not found in tuning file"; + + for (const auto &[key, value] : tuningData.asDict()) { + if (controls::AeMeteringModeNameValueMap.find(key) == + controls::AeMeteringModeNameValueMap.end()) { + LOG(RkISP1Agc, Warning) + << "Skipping unknown metering mode '" << key << "'"; + continue; + } -/* \todo Honour the FrameDurationLimits control instead of hardcoding a limit */ -static constexpr utils::Duration kMaxShutterSpeed = 60ms; + std::vector<uint8_t> weights = + value.getList<uint8_t>().value_or(std::vector<uint8_t>{}); + if (weights.size() != context.hw->numHistogramWeights) { + LOG(RkISP1Agc, Warning) + << "Failed to read metering mode'" << key << "'"; + continue; + } -/* Number of frames to wait before calculating stats on minimum exposure */ -static constexpr uint32_t kNumStartupFrames = 10; + meteringModes_[controls::AeMeteringModeNameValueMap.at(key)] = weights; + } -/* Target value to reach for the top 2% of the histogram */ -static constexpr double kEvGainTarget = 0.5; + if (meteringModes_.empty()) { + LOG(RkISP1Agc, Warning) + << "No metering modes read from tuning file; defaulting to matrix"; + int32_t meteringModeId = controls::AeMeteringModeNameValueMap.at("MeteringMatrix"); + std::vector<uint8_t> weights(context.hw->numHistogramWeights, 1); -/* - * Relative luminance target. - * - * It's a number that's chosen so that, when the camera points at a grey - * target, the resulting image brightness is considered right. - * - * \todo Why is the value different between IPU3 and RkISP1 ? - */ -static constexpr double kRelativeLuminanceTarget = 0.4; + meteringModes_[meteringModeId] = weights; + } + + std::vector<ControlValue> meteringModes; + std::vector<int> meteringModeKeys = utils::map_keys(meteringModes_); + std::transform(meteringModeKeys.begin(), meteringModeKeys.end(), + std::back_inserter(meteringModes), + [](int x) { return ControlValue(x); }); + context.ctrlMap[&controls::AeMeteringMode] = ControlInfo(meteringModes); + + return 0; +} + +uint8_t Agc::computeHistogramPredivider(const Size &size, + enum rkisp1_cif_isp_histogram_mode mode) +{ + /* + * The maximum number of pixels that could potentially be in one bin is + * if all the pixels of the image are in it, multiplied by 3 for the + * three color channels. The counter for each bin is 16 bits wide, so + * `factor` thus contains the number of times we'd wrap around. This is + * obviously the number of pixels that we need to skip to make sure + * that we don't wrap around, but we compute the square root of it + * instead, as the skip that we need to program is for both the x and y + * directions. + * + * Even though it looks like dividing into a counter of 65536 would + * overflow by 1, this is apparently fine according to the hardware + * documentation, and this successfully gets the expected documented + * predivider size for cases where: + * (width / predivider) * (height / predivider) * 3 == 65536. + * + * There's a bit of extra rounding math to make sure the rounding goes + * the correct direction so that the square of the step is big enough + * to encompass the `factor` number of pixels that we need to skip. + * + * \todo Take into account weights. That is, if the weights are low + * enough we can potentially reduce the predivider to increase + * precision. This needs some investigation however, as this hardware + * behavior is undocumented and is only an educated guess. + */ + int count = mode == RKISP1_CIF_ISP_HISTOGRAM_MODE_RGB_COMBINED ? 3 : 1; + double factor = size.width * size.height * count / 65536.0; + double root = std::sqrt(factor); + uint8_t predivider = static_cast<uint8_t>(std::ceil(root)); + + return std::clamp<uint8_t>(predivider, 3, 127); +} Agc::Agc() - : frameCount_(0), filteredExposure_(0s) { supportsRaw_ = true; } /** + * \brief Initialise the AGC algorithm from tuning files + * \param[in] context The shared IPA context + * \param[in] tuningData The YamlObject containing Agc tuning data + * + * This function calls the base class' tuningData parsers to discover which + * control values are supported. + * + * \return 0 on success or errors from the base class + */ +int Agc::init(IPAContext &context, const YamlObject &tuningData) +{ + int ret; + + ret = parseTuningData(tuningData); + if (ret) + return ret; + + const YamlObject &yamlMeteringModes = tuningData["AeMeteringMode"]; + ret = parseMeteringModes(context, yamlMeteringModes); + if (ret) + return ret; + + context.ctrlMap[&controls::AeEnable] = ControlInfo(false, true); + context.ctrlMap.merge(controls()); + + return 0; +} + +/** * \brief Configure the AGC given a configInfo * \param[in] context The shared IPA context * \param[in] configInfo The IPA configuration data @@ -81,6 +171,20 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo) context.activeState.agc.manual.exposure = context.activeState.agc.automatic.exposure; context.activeState.agc.autoEnabled = !context.configuration.raw; + context.activeState.agc.constraintMode = + static_cast<controls::AeConstraintModeEnum>(constraintModes().begin()->first); + context.activeState.agc.exposureMode = + static_cast<controls::AeExposureModeEnum>(exposureModeHelpers().begin()->first); + context.activeState.agc.meteringMode = + static_cast<controls::AeMeteringModeEnum>(meteringModes_.begin()->first); + + /* + * \todo This should probably come from FrameDurationLimits instead, + * except it's computed in the IPA and not here so we'd have to + * recompute it. + */ + context.activeState.agc.maxFrameDuration = context.configuration.sensor.maxShutterSpeed; + /* * Define the measurement window for AGC as a centered rectangle * covering 3/4 of the image width and height. @@ -90,11 +194,13 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo) context.configuration.agc.measureWindow.h_size = 3 * configInfo.outputSize.width / 4; context.configuration.agc.measureWindow.v_size = 3 * configInfo.outputSize.height / 4; - /* - * \todo Use the upcoming per-frame context API that will provide a - * frame index - */ - frameCount_ = 0; + setLimits(context.configuration.sensor.minShutterSpeed, + context.configuration.sensor.maxShutterSpeed, + context.configuration.sensor.minAnalogueGain, + context.configuration.sensor.maxAnalogueGain); + + resetFrameCount(); + return 0; } @@ -141,6 +247,34 @@ void Agc::queueRequest(IPAContext &context, frameContext.agc.exposure = agc.manual.exposure; frameContext.agc.gain = agc.manual.gain; } + + const auto &meteringMode = controls.get(controls::AeMeteringMode); + if (meteringMode) { + frameContext.agc.updateMetering = agc.meteringMode != *meteringMode; + agc.meteringMode = + static_cast<controls::AeMeteringModeEnum>(*meteringMode); + } + frameContext.agc.meteringMode = agc.meteringMode; + + const auto &exposureMode = controls.get(controls::AeExposureMode); + if (exposureMode) + agc.exposureMode = + static_cast<controls::AeExposureModeEnum>(*exposureMode); + frameContext.agc.exposureMode = agc.exposureMode; + + const auto &constraintMode = controls.get(controls::AeConstraintMode); + if (constraintMode) + agc.constraintMode = + static_cast<controls::AeConstraintModeEnum>(*constraintMode); + frameContext.agc.constraintMode = agc.constraintMode; + + const auto &frameDurationLimits = controls.get(controls::FrameDurationLimits); + if (frameDurationLimits) { + utils::Duration maxFrameDuration = + std::chrono::milliseconds((*frameDurationLimits).back()); + agc.maxFrameDuration = maxFrameDuration; + } + frameContext.agc.maxFrameDuration = agc.maxFrameDuration; } /** @@ -154,7 +288,7 @@ void Agc::prepare(IPAContext &context, const uint32_t frame, frameContext.agc.gain = context.activeState.agc.automatic.gain; } - if (frame > 0) + if (frame > 0 && !frameContext.agc.updateMetering) return; /* Configure the measurement window. */ @@ -172,14 +306,20 @@ void Agc::prepare(IPAContext &context, const uint32_t frame, params->meas.hst_config.meas_window = context.configuration.agc.measureWindow; /* Produce the luminance histogram. */ params->meas.hst_config.mode = RKISP1_CIF_ISP_HISTOGRAM_MODE_Y_HISTOGRAM; + /* Set an average weighted histogram. */ Span<uint8_t> weights{ params->meas.hst_config.hist_weight, context.hw->numHistogramWeights }; - std::fill(weights.begin(), weights.end(), 1); - /* Step size can't be less than 3. */ - params->meas.hst_config.histogram_predivider = 4; + std::vector<uint8_t> &modeWeights = meteringModes_.at(frameContext.agc.meteringMode); + std::copy(modeWeights.begin(), modeWeights.end(), weights.begin()); + + struct rkisp1_cif_isp_window window = params->meas.hst_config.meas_window; + Size windowSize = { window.h_size, window.v_size }; + params->meas.hst_config.histogram_predivider = + computeHistogramPredivider(windowSize, + static_cast<rkisp1_cif_isp_histogram_mode>(params->meas.hst_config.mode)); /* Update the configuration for histogram. */ params->module_cfg_update |= RKISP1_CIF_ISP_MODULE_HST; @@ -188,127 +328,29 @@ void Agc::prepare(IPAContext &context, const uint32_t frame, params->module_en_update |= RKISP1_CIF_ISP_MODULE_HST; } -/** - * \brief Apply a filter on the exposure value to limit the speed of changes - * \param[in] exposureValue The target exposure from the AGC algorithm - * - * The speed of the filter is adaptive, and will produce the target quicker - * during startup, or when the target exposure is within 20% of the most recent - * filter output. - * - * \return The filtered exposure - */ -utils::Duration Agc::filterExposure(utils::Duration exposureValue) -{ - double speed = 0.2; - - /* Adapt instantly if we are in startup phase. */ - if (frameCount_ < kNumStartupFrames) - speed = 1.0; - - /* - * If we are close to the desired result, go faster to avoid making - * multiple micro-adjustments. - * \todo Make this customisable? - */ - if (filteredExposure_ < 1.2 * exposureValue && - filteredExposure_ > 0.8 * exposureValue) - speed = sqrt(speed); - - filteredExposure_ = speed * exposureValue + - filteredExposure_ * (1.0 - speed); - - LOG(RkISP1Agc, Debug) << "After filtering, exposure " << filteredExposure_; - - return filteredExposure_; -} - -/** - * \brief Estimate the new exposure and gain values - * \param[inout] context The shared IPA Context - * \param[in] frameContext The FrameContext for this frame - * \param[in] yGain The gain calculated on the current brightness level - * \param[in] iqMeanGain The gain calculated based on the relative luminance target - */ -void Agc::computeExposure(IPAContext &context, IPAFrameContext &frameContext, - double yGain, double iqMeanGain) +void Agc::fillMetadata(IPAContext &context, IPAFrameContext &frameContext, + ControlList &metadata) { - IPASessionConfiguration &configuration = context.configuration; - IPAActiveState &activeState = context.activeState; - - /* Get the effective exposure and gain applied on the sensor. */ - uint32_t exposure = frameContext.sensor.exposure; - double analogueGain = frameContext.sensor.gain; - - /* Use the highest of the two gain estimates. */ - double evGain = std::max(yGain, iqMeanGain); - - utils::Duration minShutterSpeed = configuration.sensor.minShutterSpeed; - utils::Duration maxShutterSpeed = std::min(configuration.sensor.maxShutterSpeed, - kMaxShutterSpeed); - - double minAnalogueGain = std::max(configuration.sensor.minAnalogueGain, - kMinAnalogueGain); - double maxAnalogueGain = configuration.sensor.maxAnalogueGain; - - /* Consider within 1% of the target as correctly exposed. */ - if (utils::abs_diff(evGain, 1.0) < 0.01) - return; - - /* extracted from Rpi::Agc::computeTargetExposure. */ - - /* Calculate the shutter time in seconds. */ - utils::Duration currentShutter = exposure * configuration.sensor.lineDuration; - - /* - * Update the exposure value for the next computation using the values - * of exposure and gain really used by the sensor. - */ - utils::Duration effectiveExposureValue = currentShutter * analogueGain; - - LOG(RkISP1Agc, Debug) << "Actual total exposure " << currentShutter * analogueGain - << " Shutter speed " << currentShutter - << " Gain " << analogueGain - << " Needed ev gain " << evGain; - - /* - * Calculate the current exposure value for the scene as the latest - * exposure value applied multiplied by the new estimated gain. - */ - utils::Duration exposureValue = effectiveExposureValue * evGain; - - /* Clamp the exposure value to the min and max authorized. */ - utils::Duration maxTotalExposure = maxShutterSpeed * maxAnalogueGain; - exposureValue = std::min(exposureValue, maxTotalExposure); - LOG(RkISP1Agc, Debug) << "Target total exposure " << exposureValue - << ", maximum is " << maxTotalExposure; - - /* - * Divide the exposure value as new exposure and gain values. - * \todo estimate if we need to desaturate - */ - exposureValue = filterExposure(exposureValue); + utils::Duration exposureTime = context.configuration.sensor.lineDuration + * frameContext.sensor.exposure; + metadata.set(controls::AnalogueGain, frameContext.sensor.gain); + metadata.set(controls::ExposureTime, exposureTime.get<std::micro>()); + metadata.set(controls::AeEnable, frameContext.agc.autoEnabled); - /* - * Push the shutter time up to the maximum first, and only then - * increase the gain. - */ - utils::Duration shutterTime = std::clamp<utils::Duration>(exposureValue / minAnalogueGain, - minShutterSpeed, maxShutterSpeed); - double stepGain = std::clamp(exposureValue / shutterTime, - minAnalogueGain, maxAnalogueGain); - LOG(RkISP1Agc, Debug) << "Divided up shutter and gain are " - << shutterTime << " and " - << stepGain; + /* \todo Use VBlank value calculated from each frame exposure. */ + uint32_t vTotal = context.configuration.sensor.size.height + + context.configuration.sensor.defVBlank; + utils::Duration frameDuration = context.configuration.sensor.lineDuration + * vTotal; + metadata.set(controls::FrameDuration, frameDuration.get<std::micro>()); - /* Update the estimated exposure and gain. */ - activeState.agc.automatic.exposure = shutterTime / configuration.sensor.lineDuration; - activeState.agc.automatic.gain = stepGain; + metadata.set(controls::AeMeteringMode, frameContext.agc.meteringMode); + metadata.set(controls::AeExposureMode, frameContext.agc.exposureMode); + metadata.set(controls::AeConstraintMode, frameContext.agc.constraintMode); } /** * \brief Estimate the relative luminance of the frame with a given gain - * \param[in] expMeans The mean luminance values, from the RkISP1 statistics * \param[in] gain The gain to apply to the frame * * This function estimates the average relative luminance of the frame that @@ -322,8 +364,6 @@ void Agc::computeExposure(IPAContext &context, IPAFrameContext &frameContext, * YUV doesn't take into account the fact that the R, G and B components * contribute differently to the relative luminance. * - * \todo Have a dedicated YUV algorithm ? - * * The values are normalized to the [0.0, 1.0] range, where 1.0 corresponds to a * theoretical perfect reflector of 100% reference white. * @@ -332,45 +372,17 @@ void Agc::computeExposure(IPAContext &context, IPAFrameContext &frameContext, * * \return The relative luminance */ -double Agc::estimateLuminance(Span<const uint8_t> expMeans, double gain) +double Agc::estimateLuminance(double gain) const { double ySum = 0.0; /* Sum the averages, saturated to 255. */ - for (uint8_t expMean : expMeans) + for (uint8_t expMean : expMeans_) ySum += std::min(expMean * gain, 255.0); /* \todo Weight with the AWB gains */ - return ySum / expMeans.size() / 255; -} - -/** - * \brief Estimate the mean value of the top 2% of the histogram - * \param[in] hist The histogram statistics computed by the RkISP1 - * \return The mean value of the top 2% of the histogram - */ -double Agc::measureBrightness(Span<const uint32_t> hist) const -{ - Histogram histogram{ hist }; - /* Estimate the quantile mean of the top 2% of the histogram. */ - return histogram.interQuantileMean(0.98, 1.0); -} - -void Agc::fillMetadata(IPAContext &context, IPAFrameContext &frameContext, - ControlList &metadata) -{ - utils::Duration exposureTime = context.configuration.sensor.lineDuration - * frameContext.sensor.exposure; - metadata.set(controls::AnalogueGain, frameContext.sensor.gain); - metadata.set(controls::ExposureTime, exposureTime.get<std::micro>()); - - /* \todo Use VBlank value calculated from each frame exposure. */ - uint32_t vTotal = context.configuration.sensor.size.height - + context.configuration.sensor.defVBlank; - utils::Duration frameDuration = context.configuration.sensor.lineDuration - * vTotal; - metadata.set(controls::FrameDuration, frameDuration.get<std::micro>()); + return ySum / expMeans_.size() / 255; } /** @@ -404,41 +416,47 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame, const rkisp1_cif_isp_stat *params = &stats->params; ASSERT(stats->meas_type & RKISP1_CIF_ISP_STAT_AUTOEXP); - Span<const uint8_t> ae{ params->ae.exp_mean, context.hw->numAeCells }; - Span<const uint32_t> hist{ - params->hist.hist_bins, - context.hw->numHistogramBins - }; + /* The lower 4 bits are fractional and meant to be discarded. */ + Histogram hist({ params->hist.hist_bins, context.hw->numHistogramBins }, + [](uint32_t x) { return x >> 4; }); + expMeans_ = { params->ae.exp_mean, context.hw->numAeCells }; - double iqMean = measureBrightness(hist); - double iqMeanGain = kEvGainTarget * hist.size() / iqMean; + utils::Duration maxShutterSpeed = + std::clamp(frameContext.agc.maxFrameDuration, + context.configuration.sensor.minShutterSpeed, + context.configuration.sensor.maxShutterSpeed); + setLimits(context.configuration.sensor.minShutterSpeed, + maxShutterSpeed, + context.configuration.sensor.minAnalogueGain, + context.configuration.sensor.maxAnalogueGain); /* - * Estimate the gain needed to achieve a relative luminance target. To - * account for non-linearity caused by saturation, the value needs to be - * estimated in an iterative process, as multiplying by a gain will not - * increase the relative luminance by the same factor if some image - * regions are saturated. + * The Agc algorithm needs to know the effective exposure value that was + * applied to the sensor when the statistics were collected. */ - double yGain = 1.0; - double yTarget = kRelativeLuminanceTarget; - - for (unsigned int i = 0; i < 8; i++) { - double yValue = estimateLuminance(ae, yGain); - double extra_gain = std::min(10.0, yTarget / (yValue + .001)); - - yGain *= extra_gain; - LOG(RkISP1Agc, Debug) << "Y value: " << yValue - << ", Y target: " << yTarget - << ", gives gain " << yGain; - if (extra_gain < 1.01) - break; - } + utils::Duration exposureTime = context.configuration.sensor.lineDuration + * frameContext.sensor.exposure; + double analogueGain = frameContext.sensor.gain; + utils::Duration effectiveExposureValue = exposureTime * analogueGain; - computeExposure(context, frameContext, yGain, iqMeanGain); - frameCount_++; + utils::Duration shutterTime; + double aGain, dGain; + std::tie(shutterTime, aGain, dGain) = + calculateNewEv(frameContext.agc.constraintMode, + frameContext.agc.exposureMode, + hist, effectiveExposureValue); + + LOG(RkISP1Agc, Debug) + << "Divided up shutter, analogue gain and digital gain are " + << shutterTime << ", " << aGain << " and " << dGain; + + IPAActiveState &activeState = context.activeState; + /* Update the estimated exposure and gain. */ + activeState.agc.automatic.exposure = shutterTime / context.configuration.sensor.lineDuration; + activeState.agc.automatic.gain = aGain; fillMetadata(context, frameContext, metadata); + expMeans_ = {}; } REGISTER_IPA_ALGORITHM(Agc, "Agc") |