From fb8ad13dc3e38a1bb056c209f692af53588c7b84 Mon Sep 17 00:00:00 2001 From: Milan Zamazal Date: Fri, 27 Sep 2024 15:46:23 +0200 Subject: libcamera: software_isp: Move exposure+gain to an algorithm module This is the last step to fully convert software ISP to Algorithm-based processing. The newly introduced frameContext.sensor parameters are set, and the updated code moved, before calling Algorithm::process() to have the values up-to-date in stats processing. Resolves software ISP TODO #10. Signed-off-by: Milan Zamazal Reviewed-by: Kieran Bingham Reviewed-by: Umang Jain Signed-off-by: Kieran Bingham --- src/ipa/simple/algorithms/agc.cpp | 139 ++++++++++++++++++++++++++++++ src/ipa/simple/algorithms/agc.h | 33 +++++++ src/ipa/simple/algorithms/meson.build | 1 + src/ipa/simple/data/uncalibrated.yaml | 1 + src/ipa/simple/ipa_context.cpp | 11 +++ src/ipa/simple/ipa_context.h | 13 +++ src/ipa/simple/soft_simple.cpp | 157 +++++++--------------------------- src/libcamera/software_isp/TODO | 10 --- 8 files changed, 228 insertions(+), 137 deletions(-) create mode 100644 src/ipa/simple/algorithms/agc.cpp create mode 100644 src/ipa/simple/algorithms/agc.h diff --git a/src/ipa/simple/algorithms/agc.cpp b/src/ipa/simple/algorithms/agc.cpp new file mode 100644 index 00000000..783dfb8b --- /dev/null +++ b/src/ipa/simple/algorithms/agc.cpp @@ -0,0 +1,139 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2024, Red Hat Inc. + * + * Exposure and gain + */ + +#include "agc.h" + +#include + +#include + +namespace libcamera { + +LOG_DEFINE_CATEGORY(IPASoftExposure) + +namespace ipa::soft::algorithms { + +/* + * The number of bins to use for the optimal exposure calculations. + */ +static constexpr unsigned int kExposureBinsCount = 5; + +/* + * The exposure is optimal when the mean sample value of the histogram is + * in the middle of the range. + */ +static constexpr float kExposureOptimal = kExposureBinsCount / 2.0; + +/* + * The below value implements the hysteresis for the exposure adjustment. + * It is small enough to have the exposure close to the optimal, and is big + * enough to prevent the exposure from wobbling around the optimal value. + */ +static constexpr float kExposureSatisfactory = 0.2; + +Agc::Agc() +{ +} + +void Agc::updateExposure(IPAContext &context, double exposureMSV) +{ + /* + * kExpDenominator of 10 gives ~10% increment/decrement; + * kExpDenominator of 5 - about ~20% + */ + static constexpr uint8_t kExpDenominator = 10; + static constexpr uint8_t kExpNumeratorUp = kExpDenominator + 1; + static constexpr uint8_t kExpNumeratorDown = kExpDenominator - 1; + + double next; + int32_t &exposure = context.activeState.agc.exposure; + double &again = context.activeState.agc.again; + + if (exposureMSV < kExposureOptimal - kExposureSatisfactory) { + next = exposure * kExpNumeratorUp / kExpDenominator; + if (next - exposure < 1) + exposure += 1; + else + exposure = next; + if (exposure >= context.configuration.agc.exposureMax) { + next = again * kExpNumeratorUp / kExpDenominator; + if (next - again < context.configuration.agc.againMinStep) + again += context.configuration.agc.againMinStep; + else + again = next; + } + } + + if (exposureMSV > kExposureOptimal + kExposureSatisfactory) { + if (exposure == context.configuration.agc.exposureMax && + again > context.configuration.agc.againMin) { + next = again * kExpNumeratorDown / kExpDenominator; + if (again - next < context.configuration.agc.againMinStep) + again -= context.configuration.agc.againMinStep; + else + again = next; + } else { + next = exposure * kExpNumeratorDown / kExpDenominator; + if (exposure - next < 1) + exposure -= 1; + else + exposure = next; + } + } + + exposure = std::clamp(exposure, context.configuration.agc.exposureMin, + context.configuration.agc.exposureMax); + again = std::clamp(again, context.configuration.agc.againMin, + context.configuration.agc.againMax); + + LOG(IPASoftExposure, Debug) + << "exposureMSV " << exposureMSV + << " exp " << exposure << " again " << again; +} + +void Agc::process(IPAContext &context, + [[maybe_unused]] const uint32_t frame, + [[maybe_unused]] IPAFrameContext &frameContext, + const SwIspStats *stats, + [[maybe_unused]] ControlList &metadata) +{ + /* + * Calculate Mean Sample Value (MSV) according to formula from: + * https://www.araa.asn.au/acra/acra2007/papers/paper84final.pdf + */ + const auto &histogram = stats->yHistogram; + const unsigned int blackLevelHistIdx = + context.activeState.blc.level / (256 / SwIspStats::kYHistogramSize); + const unsigned int histogramSize = + SwIspStats::kYHistogramSize - blackLevelHistIdx; + const unsigned int yHistValsPerBin = histogramSize / kExposureBinsCount; + const unsigned int yHistValsPerBinMod = + histogramSize / (histogramSize % kExposureBinsCount + 1); + int exposureBins[kExposureBinsCount] = {}; + unsigned int denom = 0; + unsigned int num = 0; + + for (unsigned int i = 0; i < histogramSize; i++) { + unsigned int idx = (i - (i / yHistValsPerBinMod)) / yHistValsPerBin; + exposureBins[idx] += histogram[blackLevelHistIdx + i]; + } + + for (unsigned int i = 0; i < kExposureBinsCount; i++) { + LOG(IPASoftExposure, Debug) << i << ": " << exposureBins[i]; + denom += exposureBins[i]; + num += exposureBins[i] * (i + 1); + } + + float exposureMSV = (denom == 0 ? 0 : static_cast(num) / denom); + updateExposure(context, exposureMSV); +} + +REGISTER_IPA_ALGORITHM(Agc, "Agc") + +} /* namespace ipa::soft::algorithms */ + +} /* namespace libcamera */ diff --git a/src/ipa/simple/algorithms/agc.h b/src/ipa/simple/algorithms/agc.h new file mode 100644 index 00000000..ad5fca9f --- /dev/null +++ b/src/ipa/simple/algorithms/agc.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2024, Red Hat Inc. + * + * Exposure and gain + */ + +#pragma once + +#include "algorithm.h" + +namespace libcamera { + +namespace ipa::soft::algorithms { + +class Agc : public Algorithm +{ +public: + Agc(); + ~Agc() = default; + + void process(IPAContext &context, const uint32_t frame, + IPAFrameContext &frameContext, + const SwIspStats *stats, + ControlList &metadata) override; + +private: + void updateExposure(IPAContext &context, double exposureMSV); +}; + +} /* namespace ipa::soft::algorithms */ + +} /* namespace libcamera */ diff --git a/src/ipa/simple/algorithms/meson.build b/src/ipa/simple/algorithms/meson.build index f575611e..37a2eb53 100644 --- a/src/ipa/simple/algorithms/meson.build +++ b/src/ipa/simple/algorithms/meson.build @@ -2,6 +2,7 @@ soft_simple_ipa_algorithms = files([ 'awb.cpp', + 'agc.cpp', 'blc.cpp', 'lut.cpp', ]) diff --git a/src/ipa/simple/data/uncalibrated.yaml b/src/ipa/simple/data/uncalibrated.yaml index 893a0b92..3f147112 100644 --- a/src/ipa/simple/data/uncalibrated.yaml +++ b/src/ipa/simple/data/uncalibrated.yaml @@ -6,4 +6,5 @@ algorithms: - BlackLevel: - Awb: - Lut: + - Agc: ... diff --git a/src/ipa/simple/ipa_context.cpp b/src/ipa/simple/ipa_context.cpp index 5fa492cb..3f94bbeb 100644 --- a/src/ipa/simple/ipa_context.cpp +++ b/src/ipa/simple/ipa_context.cpp @@ -77,6 +77,17 @@ namespace libcamera::ipa::soft { * \brief Gain of blue color */ +/** + * \var IPAActiveState::agc + * \brief Context for the AGC algorithm + * + * \var IPAActiveState::agc.exposure + * \brief Current exposure value + * + * \var IPAActiveState::agc.again + * \brief Current analog gain value + */ + /** * \var IPAActiveState::gamma * \brief Context for gamma in the Colors algorithm diff --git a/src/ipa/simple/ipa_context.h b/src/ipa/simple/ipa_context.h index cf1ef3fd..3519f20f 100644 --- a/src/ipa/simple/ipa_context.h +++ b/src/ipa/simple/ipa_context.h @@ -18,6 +18,10 @@ namespace ipa::soft { struct IPASessionConfiguration { float gamma; + struct { + int32_t exposureMin, exposureMax; + double againMin, againMax, againMinStep; + } agc; }; struct IPAActiveState { @@ -31,6 +35,11 @@ struct IPAActiveState { double blue; } gains; + struct { + int32_t exposure; + double again; + } agc; + static constexpr unsigned int kGammaLookupSize = 1024; struct { std::array gammaTable; @@ -39,6 +48,10 @@ struct IPAActiveState { }; struct IPAFrameContext : public FrameContext { + struct { + uint32_t exposure; + double gain; + } sensor; }; struct IPAContext { diff --git a/src/ipa/simple/soft_simple.cpp b/src/ipa/simple/soft_simple.cpp index 60310a8e..b28c7039 100644 --- a/src/ipa/simple/soft_simple.cpp +++ b/src/ipa/simple/soft_simple.cpp @@ -34,23 +34,6 @@ LOG_DEFINE_CATEGORY(IPASoft) namespace ipa::soft { -/* - * The number of bins to use for the optimal exposure calculations. - */ -static constexpr unsigned int kExposureBinsCount = 5; - -/* - * The exposure is optimal when the mean sample value of the histogram is - * in the middle of the range. - */ -static constexpr float kExposureOptimal = kExposureBinsCount / 2.0; - -/* - * The below value implements the hysteresis for the exposure adjustment. - * It is small enough to have the exposure close to the optimal, and is big - * enough to prevent the exposure from wobbling around the optimal value. - */ -static constexpr float kExposureSatisfactory = 0.2; /* Maximum number of frame contexts to be held */ static constexpr uint32_t kMaxFrameContexts = 16; @@ -58,8 +41,7 @@ class IPASoftSimple : public ipa::soft::IPASoftInterface, public Module { public: IPASoftSimple() - : params_(nullptr), stats_(nullptr), - context_({ {}, {}, { kMaxFrameContexts } }) + : context_({ {}, {}, { kMaxFrameContexts } }) { } @@ -92,11 +74,6 @@ private: /* Local parameter storage */ struct IPAContext context_; - - int32_t exposureMin_, exposureMax_; - int32_t exposure_; - double againMin_, againMax_, againMinStep_; - double again_; }; IPASoftSimple::~IPASoftSimple() @@ -207,20 +184,23 @@ int IPASoftSimple::configure(const IPAConfigInfo &configInfo) const ControlInfo &exposureInfo = sensorInfoMap_.find(V4L2_CID_EXPOSURE)->second; const ControlInfo &gainInfo = sensorInfoMap_.find(V4L2_CID_ANALOGUE_GAIN)->second; - exposureMin_ = exposureInfo.min().get(); - exposureMax_ = exposureInfo.max().get(); - if (!exposureMin_) { + context_.configuration.agc.exposureMin = exposureInfo.min().get(); + context_.configuration.agc.exposureMax = exposureInfo.max().get(); + if (!context_.configuration.agc.exposureMin) { LOG(IPASoft, Warning) << "Minimum exposure is zero, that can't be linear"; - exposureMin_ = 1; + context_.configuration.agc.exposureMin = 1; } int32_t againMin = gainInfo.min().get(); int32_t againMax = gainInfo.max().get(); if (camHelper_) { - againMin_ = camHelper_->gain(againMin); - againMax_ = camHelper_->gain(againMax); - againMinStep_ = (againMax_ - againMin_) / 100.0; + context_.configuration.agc.againMin = camHelper_->gain(againMin); + context_.configuration.agc.againMax = camHelper_->gain(againMax); + context_.configuration.agc.againMinStep = + (context_.configuration.agc.againMax - + context_.configuration.agc.againMin) / + 100.0; } else { /* * The camera sensor gain (g) is usually not equal to the value written @@ -232,13 +212,14 @@ int IPASoftSimple::configure(const IPAConfigInfo &configInfo) * the AGC algorithm (abrupt near one edge, and very small near the * other) we limit the range of the gain values used. */ - againMax_ = againMax; + context_.configuration.agc.againMax = againMax; if (!againMin) { LOG(IPASoft, Warning) << "Minimum gain is zero, that can't be linear"; - againMin_ = std::min(100, againMin / 2 + againMax / 2); + context_.configuration.agc.againMin = + std::min(100, againMin / 2 + againMax / 2); } - againMinStep_ = 1.0; + context_.configuration.agc.againMinStep = 1.0; } for (auto const &algo : algorithms()) { @@ -247,9 +228,12 @@ int IPASoftSimple::configure(const IPAConfigInfo &configInfo) return ret; } - LOG(IPASoft, Info) << "Exposure " << exposureMin_ << "-" << exposureMax_ - << ", gain " << againMin_ << "-" << againMax_ - << " (" << againMinStep_ << ")"; + LOG(IPASoft, Info) + << "Exposure " << context_.configuration.agc.exposureMin << "-" + << context_.configuration.agc.exposureMax + << ", gain " << context_.configuration.agc.againMin << "-" + << context_.configuration.agc.againMax + << " (" << context_.configuration.agc.againMinStep << ")"; return 0; } @@ -284,6 +268,12 @@ void IPASoftSimple::processStats(const uint32_t frame, const ControlList &sensorControls) { IPAFrameContext &frameContext = context_.frameContexts.get(frame); + + frameContext.sensor.exposure = + sensorControls.get(V4L2_CID_EXPOSURE).get(); + int32_t again = sensorControls.get(V4L2_CID_ANALOGUE_GAIN).get(); + frameContext.sensor.gain = camHelper_ ? camHelper_->gain(again) : again; + /* * Software ISP currently does not produce any metadata. Use an empty * ControlList for now. @@ -294,37 +284,6 @@ void IPASoftSimple::processStats(const uint32_t frame, for (auto const &algo : algorithms()) algo->process(context_, frame, frameContext, stats_, metadata); - /* \todo Switch to the libipa/algorithm.h API someday. */ - - /* - * Calculate Mean Sample Value (MSV) according to formula from: - * https://www.araa.asn.au/acra/acra2007/papers/paper84final.pdf - */ - const uint8_t blackLevel = context_.activeState.blc.level; - const unsigned int blackLevelHistIdx = - blackLevel / (256 / SwIspStats::kYHistogramSize); - const unsigned int histogramSize = - SwIspStats::kYHistogramSize - blackLevelHistIdx; - const unsigned int yHistValsPerBin = histogramSize / kExposureBinsCount; - const unsigned int yHistValsPerBinMod = - histogramSize / (histogramSize % kExposureBinsCount + 1); - int exposureBins[kExposureBinsCount] = {}; - unsigned int denom = 0; - unsigned int num = 0; - - for (unsigned int i = 0; i < histogramSize; i++) { - unsigned int idx = (i - (i / yHistValsPerBinMod)) / yHistValsPerBin; - exposureBins[idx] += stats_->yHistogram[blackLevelHistIdx + i]; - } - - for (unsigned int i = 0; i < kExposureBinsCount; i++) { - LOG(IPASoft, Debug) << i << ": " << exposureBins[i]; - denom += exposureBins[i]; - num += exposureBins[i] * (i + 1); - } - - float exposureMSV = static_cast(num) / denom; - /* Sanity check */ if (!sensorControls.contains(V4L2_CID_EXPOSURE) || !sensorControls.contains(V4L2_CID_ANALOGUE_GAIN)) { @@ -332,70 +291,14 @@ void IPASoftSimple::processStats(const uint32_t frame, return; } - exposure_ = sensorControls.get(V4L2_CID_EXPOSURE).get(); - int32_t again = sensorControls.get(V4L2_CID_ANALOGUE_GAIN).get(); - again_ = camHelper_ ? camHelper_->gain(again) : again; - - updateExposure(exposureMSV); - ControlList ctrls(sensorInfoMap_); - ctrls.set(V4L2_CID_EXPOSURE, exposure_); + auto &againNew = context_.activeState.agc.again; + ctrls.set(V4L2_CID_EXPOSURE, context_.activeState.agc.exposure); ctrls.set(V4L2_CID_ANALOGUE_GAIN, - static_cast(camHelper_ ? camHelper_->gainCode(again_) : again_)); + static_cast(camHelper_ ? camHelper_->gainCode(againNew) : againNew)); setSensorControls.emit(ctrls); - - LOG(IPASoft, Debug) << "exposureMSV " << exposureMSV - << " exp " << exposure_ << " again " << again_ - << " black level " << static_cast(blackLevel); -} - -void IPASoftSimple::updateExposure(double exposureMSV) -{ - /* - * kExpDenominator of 10 gives ~10% increment/decrement; - * kExpDenominator of 5 - about ~20% - */ - static constexpr uint8_t kExpDenominator = 10; - static constexpr uint8_t kExpNumeratorUp = kExpDenominator + 1; - static constexpr uint8_t kExpNumeratorDown = kExpDenominator - 1; - - double next; - - if (exposureMSV < kExposureOptimal - kExposureSatisfactory) { - next = exposure_ * kExpNumeratorUp / kExpDenominator; - if (next - exposure_ < 1) - exposure_ += 1; - else - exposure_ = next; - if (exposure_ >= exposureMax_) { - next = again_ * kExpNumeratorUp / kExpDenominator; - if (next - again_ < againMinStep_) - again_ += againMinStep_; - else - again_ = next; - } - } - - if (exposureMSV > kExposureOptimal + kExposureSatisfactory) { - if (exposure_ == exposureMax_ && again_ > againMin_) { - next = again_ * kExpNumeratorDown / kExpDenominator; - if (again_ - next < againMinStep_) - again_ -= againMinStep_; - else - again_ = next; - } else { - next = exposure_ * kExpNumeratorDown / kExpDenominator; - if (exposure_ - next < 1) - exposure_ -= 1; - else - exposure_ = next; - } - } - - exposure_ = std::clamp(exposure_, exposureMin_, exposureMax_); - again_ = std::clamp(again_, againMin_, againMax_); } std::string IPASoftSimple::logPrefix() const diff --git a/src/libcamera/software_isp/TODO b/src/libcamera/software_isp/TODO index 8eeede46..a50db668 100644 --- a/src/libcamera/software_isp/TODO +++ b/src/libcamera/software_isp/TODO @@ -199,16 +199,6 @@ Yes, because, well... all the other IPAs were doing that... --- -10. Switch to libipa/algorithm.h API in processStats - ->> void IPASoftSimple::processStats(const ControlList &sensorControls) ->> -> Do you envision switching to the libipa/algorithm.h API at some point ? - -At some point, yes. - ---- - 13. Improve black level and colour gains application I think the black level should eventually be moved before debayering, and -- cgit v1.2.1