[libcamera-devel] [PATCH v4 10/11] ipa: rkisp1: Introduce AGC
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Wed Nov 24 23:58:05 CET 2021
On Wed, Nov 24, 2021 at 02:30:23PM +0000, Kieran Bingham wrote:
> Quoting Jean-Michel Hautbois (2021-11-24 13:40:18)
> > Now that we have IPAContext and Algorithm, we can implement a simple AGC
> > based on the IPU3 one. It is very similar, except that there is no
> > histogram used for an inter quantile mean. The RkISP1 is returning a 5x5
> > array (for V10) of luminance means. Estimating the relative luminance is
> > thus a simple mean of all the blocks already calculated by the ISP.
> >
> > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
> >
> > ---
> > v4:
> > - use #pragma once
> > - Return filtered value from the function
> > - Store line duration in IPASessionConfiguration
> > - Use the hw revision to configure the number of AE cells
> > ---
> > src/ipa/rkisp1/algorithms/agc.cpp | 279 ++++++++++++++++++++++++++
> > src/ipa/rkisp1/algorithms/agc.h | 45 +++++
> > src/ipa/rkisp1/algorithms/meson.build | 1 +
> > src/ipa/rkisp1/ipa_context.cpp | 45 +++++
> > src/ipa/rkisp1/ipa_context.h | 19 ++
> > src/ipa/rkisp1/rkisp1.cpp | 73 ++++---
> > 6 files changed, 424 insertions(+), 38 deletions(-)
> > create mode 100644 src/ipa/rkisp1/algorithms/agc.cpp
> > create mode 100644 src/ipa/rkisp1/algorithms/agc.h
> >
> > diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp
> > new file mode 100644
> > index 00000000..84ff8c7a
> > --- /dev/null
> > +++ b/src/ipa/rkisp1/algorithms/agc.cpp
> > @@ -0,0 +1,279 @@
> > +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> > +/*
> > + * Copyright (C) 2021, Ideas On Board
> > + *
> > + * agc.cpp - AGC/AEC mean-based control algorithm
> > + */
> > +
> > +#include "agc.h"
> > +
> > +#include <algorithm>
> > +#include <chrono>
> > +#include <cmath>
> > +
> > +#include <libcamera/base/log.h>
> > +
> > +#include <libcamera/ipa/core_ipa_interface.h>
> > +
> > +/**
> > + * \file agc.h
> > + */
> > +
> > +namespace libcamera {
> > +
> > +using namespace std::literals::chrono_literals;
> > +
> > +namespace ipa::rkisp1::algorithms {
> > +
> > +/**
> > + * \class Agc
> > + * \brief A mean-based auto-exposure algorithm
> > + */
> > +
> > +LOG_DEFINE_CATEGORY(RkISP1Agc)
> > +
> > +/* Limits for analogue gain values */
> > +static constexpr double kMinAnalogueGain = 1.0;
> > +static constexpr double kMaxAnalogueGain = 8.0;
> > +
> > +/* \todo Honour the FrameDurationLimits control instead of hardcoding a limit */
> > +static constexpr utils::Duration kMaxShutterSpeed = 60ms;
> > +
> > +/* Number of frames to wait before calculating stats on minimum exposure */
> > +static constexpr uint32_t kNumStartupFrames = 10;
> > +
> > +/*
> > + * 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.
> > + */
> > +static constexpr double kRelativeLuminanceTarget = 0.4;
> > +
> > +Agc::Agc()
> > + : frameCount_(0), currentExposure_(0s)
> > +{
> > +}
> > +
> > +/**
> > + * \brief Configure the AGC given a configInfo
> > + * \param[in] context The shared IPA context
> > + * \param[in] configInfo The IPA configuration data
> > + *
> > + * \return 0
> > + */
> > +int Agc::configure(IPAContext &context,
> > + [[maybe_unused]] const IPACameraSensorInfo &configInfo)
> > +{
> > + /* Configure the default exposure and gain. */
> > + context.frameContext.agc.gain = std::max(context.configuration.agc.minAnalogueGain, kMinAnalogueGain);
> > + context.frameContext.agc.exposure = 10ms / context.configuration.agc.lineDuration;
> > +
> > + /*
> > + * According to the RkISP1 documentation:
> > + * - versions <= V11 have RKISP1_CIF_ISP_AE_MEAN_MAX_V10 entries,
> > + * - versions >= V12 have RKISP1_CIF_ISP_AE_MEAN_MAX_V12 entries.
> > + */
> > + if (context.configuration.hw.revision < RKISP1_V12)
> > + numCells_ = RKISP1_CIF_ISP_AE_MEAN_MAX_V10;
> > + else
> > + numCells_ = RKISP1_CIF_ISP_AE_MEAN_MAX_V12;
> > +
> > + return 0;
> > +}
> > +
> > +/**
> > + * \brief Apply a filter on the exposure value to limit the speed of changes
> > + */
> > +utils::Duration Agc::filterExposure()
> > +{
> > + utils::Duration filteredExposure = currentExposure_;
> > + double speed = 0.2;
> > +
> > + /* Adapt instantly if we are in startup phase */
> > + if (frameCount_ < kNumStartupFrames)
> > + speed = 1.0;
> > +
> > + if (filteredExposure == 0s) {
> > + filteredExposure = currentExposure_;
>
> Is this right?
>
> I read this as:
>
> {
> utils::Duration filteredExposure = currentExposure_;
> if (filteredExposure == 0s) {
> filteredExposure = currentExposure_; // already set.
> }
> return filteredExposure; // Return 0s.
> }
>
>
> > + } else {
> > + /*
> > + * If we are close to the desired result, go faster to avoid making
> > + * multiple micro-adjustments.
> > + * \todo Make this customisable?
> > + */
> > + if (filteredExposure < 1.2 * currentExposure_ &&
> > + filteredExposure > 0.8 * currentExposure_)
> > + speed = sqrt(speed);
>
> And this now reads as:
> fE = cE;
>
> if (fE < 1.2 * cE) && (fe > 0.8 * cE) // Always true.
> speed = sqrt(speed);
Doesn't look right indeed. As a side note, I'd pass the currentExposure_
to the function instead of storing it in a member variable. It's the
filtered exposure you need to store to implement an IIR filter (I would
still return the filter output from this function, even if stored as a
member variable, so that filteredExposure_ would only be used internally
here).
A similar fix for the IPU3 IPA would be nice.
> > +
> > + filteredExposure = speed * currentExposure_ +
> > + filteredExposure * (1.0 - speed);
> > + }
> > +
> > + LOG(RkISP1Agc, Debug) << "After filtering, total_exposure " << filteredExposure;
> > +
> > + return filteredExposure;
> > +}
> > +
> > +/**
> > + * \brief Estimate the new exposure and gain values
> > + * \param[inout] frameContext The shared IPA frame Context
> > + * \param[in] yGain The gain calculated on the current brightness level
> > + */
> > +void Agc::computeExposure(IPAContext &context, double yGain)
> > +{
> > + IPASessionConfiguration &configuration = context.configuration;
> > + IPAFrameContext &frameContext = context.frameContext;
> > +
> > + /* Get the effective exposure and gain applied on the sensor. */
> > + uint32_t exposure = frameContext.sensor.exposure;
> > + double analogueGain = frameContext.sensor.gain;
> > +
> > + utils::Duration minShutterSpeed = configuration.agc.minShutterSpeed;
> > + utils::Duration maxShutterSpeed = std::min(configuration.agc.maxShutterSpeed,
> > + kMaxShutterSpeed);
> > +
> > + double minAnalogueGain = std::max(configuration.agc.minAnalogueGain,
> > + kMinAnalogueGain);
> > + double maxAnalogueGain = std::min(configuration.agc.maxAnalogueGain,
> > + kMaxAnalogueGain);
> > +
> > + /* Consider within 1% of the target as correctly exposed */
> > + if (std::abs(yGain - 1.0) < 0.01)
> > + LOG(RkISP1Agc, Debug) << "We are well exposed (iqMean = "
> > + << yGain << ")";
> > +
> > + /* extracted from Rpi::Agc::computeTargetExposure */
> > +
> > + /* Calculate the shutter time in seconds */
> > + utils::Duration currentShutter = exposure * configuration.agc.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 " << yGain;
> > +
> > + /*
> > + * Calculate the current exposure value for the scene as the latest
> > + * exposure value applied multiplied by the new estimated gain.
> > + */
> > + currentExposure_ = effectiveExposureValue * yGain;
> > +
> > + /* Clamp the exposure value to the min and max authorized */
> > + utils::Duration maxTotalExposure = maxShutterSpeed * maxAnalogueGain;
> > + currentExposure_ = std::min(currentExposure_, maxTotalExposure);
> > + LOG(RkISP1Agc, Debug) << "Target total exposure " << currentExposure_
> > + << ", maximum is " << maxTotalExposure;
> > +
> > + /*
> > + * Divide the exposure value as new exposure and gain values
> > + * \todo: estimate if we need to desaturate
> > + */
> > + utils::Duration exposureValue = filterExposure();
> > + utils::Duration shutterTime;
> > +
> > + /*
> > + * Push the shutter time up to the maximum first, and only then
> > + * increase the gain.
> > + */
> > + 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;
> > +
> > + /* Update the estimated exposure and gain. */
> > + frameContext.agc.exposure = shutterTime / configuration.agc.lineDuration;
> > + frameContext.agc.gain = stepGain;
> > +}
> > +
> > +/**
> > + * \brief Estimate the relative luminance of the frame with a given gain
> > + * \param[in] ae The RkISP1 statistics and ISP results
> > + * \param[in] gain The gain calculated on the current brightness level
> > + * \return The relative luminance
> > + *
> > + * This function estimates the average relative luminance of the frame that
> > + * would be output by the sensor if an additional \a gain was applied.
> > + *
> > + * The estimation is based on the AE statistics for the current frame. Y
> > + * averages for all cells are first multiplied by the gain, and then saturated
> > + * to approximate the sensor behaviour at high brightness values. The
> > + * approximation is quite rough, as it doesn't take into account non-linearities
> > + * when approaching saturation.
> > + *
> > + * The values are normalized to the [0.0, 1.0] range, where 1.0 corresponds to a
> > + * theoretical perfect reflector of 100% reference white.
> > + *
> > + * More detailed information can be found in:
> > + * https://en.wikipedia.org/wiki/Relative_luminance
> > + */
> > +double Agc::estimateLuminance(const rkisp1_cif_isp_ae_stat *ae,
> > + double gain)
> > +{
> > + double ySum = 0.0;
> > + unsigned int num = 0;
> > +
> > + /* Sum the averages, saturated to 255. */
> > + for (unsigned int aeCell = 0; aeCell < numCells_; aeCell++) {
> > + ySum += std::min(ae->exp_mean[aeCell] * gain, 255.0);
> > + num++;
> > + }
> > +
> > + /* \todo Weight with the AWB gains */
> > +
> > + return ySum / num / 255;
Drop num and replace it with numCells_.
> > +}
> > +
> > +/**
> > + * \brief Process RkISP1 statistics, and run AGC operations
> > + * \param[in] context The shared IPA context
> > + * \param[in] stats The RKIsp1 statistics and ISP results
> > + *
> > + * Identify the current image brightness, and use that to estimate the optimal
> > + * new exposure and gain for the scene.
> > + */
> > +void Agc::process(IPAContext &context, const rkisp1_stat_buffer *stats)
> > +{
> > + const rkisp1_cif_isp_stat *params = &stats->params;
> > + ASSERT(stats->meas_type & RKISP1_CIF_ISP_STAT_AUTOEXP);
> > +
> > + const rkisp1_cif_isp_ae_stat *ae = ¶ms->ae;
> > +
> > + /*
> > + * 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.
> > + */
> > + 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;
> > + }
> > +
> > + computeExposure(context, yGain);
> > + frameCount_++;
> > +}
> > +
> > +} /* namespace ipa::rkisp1::algorithms */
> > +
> > +} /* namespace libcamera */
> > diff --git a/src/ipa/rkisp1/algorithms/agc.h b/src/ipa/rkisp1/algorithms/agc.h
> > new file mode 100644
> > index 00000000..a59ae9c8
> > --- /dev/null
> > +++ b/src/ipa/rkisp1/algorithms/agc.h
> > @@ -0,0 +1,45 @@
> > +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> > +/*
> > + * Copyright (C) 2021, Ideas On Board
> > + *
> > + * agc.h - RkISP1 AGC/AEC mean-based control algorithm
> > + */
> > +#pragma once
> > +
> > +#include <linux/rkisp1-config.h>
> > +
> > +#include <libcamera/base/utils.h>
> > +
> > +#include <libcamera/geometry.h>
> > +
> > +#include "algorithm.h"
> > +
> > +namespace libcamera {
> > +
> > +struct IPACameraSensorInfo;
> > +
> > +namespace ipa::rkisp1::algorithms {
> > +
> > +class Agc : public Algorithm
> > +{
> > +public:
> > + Agc();
> > + ~Agc() = default;
> > +
> > + int configure(IPAContext &context, const IPACameraSensorInfo &configInfo) override;
> > + void process(IPAContext &context, const rkisp1_stat_buffer *stats) override;
> > +
> > +private:
> > + void computeExposure(IPAContext &Context, double yGain);
> > + utils::Duration filterExposure();
> > + double estimateLuminance(const rkisp1_cif_isp_ae_stat *ae, double gain);
> > +
> > + uint64_t frameCount_;
> > +
> > + uint32_t numCells_;
> > +
> > + utils::Duration currentExposure_;
> > +};
> > +
> > +} /* namespace ipa::rkisp1::algorithms */
> > +} /* namespace libcamera */
> > diff --git a/src/ipa/rkisp1/algorithms/meson.build b/src/ipa/rkisp1/algorithms/meson.build
> > index 1c6c59cf..a19c1a4f 100644
> > --- a/src/ipa/rkisp1/algorithms/meson.build
> > +++ b/src/ipa/rkisp1/algorithms/meson.build
> > @@ -1,4 +1,5 @@
> > # SPDX-License-Identifier: CC0-1.0
> >
> > rkisp1_ipa_algorithms = files([
> > + 'agc.cpp',
> > ])
> > diff --git a/src/ipa/rkisp1/ipa_context.cpp b/src/ipa/rkisp1/ipa_context.cpp
> > index 6b53dfdf..dff00362 100644
> > --- a/src/ipa/rkisp1/ipa_context.cpp
> > +++ b/src/ipa/rkisp1/ipa_context.cpp
> > @@ -56,6 +56,24 @@ namespace libcamera::ipa::rkisp1 {
> > */
> >
> > /**
> > + * \var IPASessionConfiguration::agc
> > + * \brief AGC parameters configuration of the IPA
> > + *
> > + * \var IPASessionConfiguration::agc.minShutterSpeed
> > + * \brief Minimum shutter speed supported with the configured sensor
> > + *
> > + * \var IPASessionConfiguration::agc.maxShutterSpeed
> > + * \brief Maximum shutter speed supported with the configured sensor
> > + *
> > + * \var IPASessionConfiguration::agc.minAnalogueGain
> > + * \brief Minimum analogue gain supported with the configured sensor
> > + *
> > + * \var IPASessionConfiguration::agc.maxAnalogueGain
> > + * \brief Maximum analogue gain supported with the configured sensor
> > + *
> > + * \var IPASessionConfiguration::agc.lineDuration
> > + * \brief Line duration in microseconds
> > + *
> > * \var IPASessionConfiguration::hw
> > * \brief RkISP1-specific hardware information
> > *
> > @@ -63,4 +81,31 @@ namespace libcamera::ipa::rkisp1 {
> > * \brief Hardware revision of the ISP
> > */
> >
> > +/**
> > + * \var IPAFrameContext::agc
> > + * \brief Context for the Automatic Gain Control algorithm
> > + *
> > + * The exposure and gain determined are expected to be applied to the sensor
> > + * at the earliest opportunity.
> > + *
> > + * \var IPAFrameContext::agc.exposure
> > + * \brief Exposure time expressed as a number of lines
> > + *
> > + * \var IPAFrameContext::agc.gain
> > + * \brief Analogue gain multiplier
> > + *
> > + * The gain should be adapted to the sensor specific gain code before applying.
> > + */
> > +
> > +/**
> > + * \var IPAFrameContext::sensor
> > + * \brief Effective sensor values
> > + *
> > + * \var IPAFrameContext::sensor.exposure
> > + * \brief Exposure time expressed as a number of lines
> > + *
> > + * \var IPAFrameContext::sensor.gain
> > + * \brief Analogue gain multiplier
> > + */
> > +
> > } /* namespace libcamera::ipa::rkisp1 */
> > diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h
> > index f9ac6833..653d7e65 100644
> > --- a/src/ipa/rkisp1/ipa_context.h
> > +++ b/src/ipa/rkisp1/ipa_context.h
> > @@ -9,17 +9,36 @@
> >
> > #include <linux/rkisp1-config.h>
> >
> > +#include <libcamera/base/utils.h>
> > +
> > namespace libcamera {
> >
> > namespace ipa::rkisp1 {
> >
> > struct IPASessionConfiguration {
> > + struct {
> > + utils::Duration minShutterSpeed;
> > + utils::Duration maxShutterSpeed;
> > + double minAnalogueGain;
> > + double maxAnalogueGain;
> > + utils::Duration lineDuration;
> > + } agc;
> > +
> > struct {
> > rkisp1_cif_isp_version revision;
> > } hw;
> > };
> >
> > struct IPAFrameContext {
> > + struct {
> > + uint32_t exposure;
> > + double gain;
> > + } agc;
> > +
> > + struct {
> > + uint32_t exposure;
> > + double gain;
> > + } sensor;
> > };
> >
> > struct IPAContext {
> > diff --git a/src/ipa/rkisp1/rkisp1.cpp b/src/ipa/rkisp1/rkisp1.cpp
> > index 59676a70..5c0a0330 100644
> > --- a/src/ipa/rkisp1/rkisp1.cpp
> > +++ b/src/ipa/rkisp1/rkisp1.cpp
> > @@ -25,6 +25,7 @@
> >
> > #include <libcamera/internal/mapped_framebuffer.h>
> >
> > +#include "algorithms/agc.h"
> > #include "algorithms/algorithm.h"
> > #include "libipa/camera_sensor_helper.h"
> >
> > @@ -34,6 +35,8 @@ namespace libcamera {
> >
> > LOG_DEFINE_CATEGORY(IPARkISP1)
> >
> > +using namespace std::literals::chrono_literals;
> > +
> > namespace ipa::rkisp1 {
> >
> > class IPARkISP1 : public IPARkISP1Interface
> > @@ -75,7 +78,6 @@ private:
> >
> > /* revision-specific data */
> > rkisp1_cif_isp_version hwRevision_;
> > - unsigned int hwAeMeanMax_;
> > unsigned int hwHistBinNMax_;
> > unsigned int hwGammaOutMaxSamples_;
> > unsigned int hwHistogramWeightGridsSize_;
> > @@ -95,13 +97,11 @@ int IPARkISP1::init(const IPASettings &settings, unsigned int hwRevision)
> > /* \todo Add support for other revisions */
> > switch (hwRevision) {
> > case RKISP1_V10:
> > - hwAeMeanMax_ = RKISP1_CIF_ISP_AE_MEAN_MAX_V10;
> > hwHistBinNMax_ = RKISP1_CIF_ISP_HIST_BIN_N_MAX_V10;
> > hwGammaOutMaxSamples_ = RKISP1_CIF_ISP_GAMMA_OUT_MAX_SAMPLES_V10;
> > hwHistogramWeightGridsSize_ = RKISP1_CIF_ISP_HISTOGRAM_WEIGHT_GRIDS_SIZE_V10;
> > break;
> > case RKISP1_V12:
> > - hwAeMeanMax_ = RKISP1_CIF_ISP_AE_MEAN_MAX_V12;
> > hwHistBinNMax_ = RKISP1_CIF_ISP_HIST_BIN_N_MAX_V12;
> > hwGammaOutMaxSamples_ = RKISP1_CIF_ISP_GAMMA_OUT_MAX_SAMPLES_V12;
> > hwHistogramWeightGridsSize_ = RKISP1_CIF_ISP_HISTOGRAM_WEIGHT_GRIDS_SIZE_V12;
> > @@ -126,6 +126,9 @@ int IPARkISP1::init(const IPASettings &settings, unsigned int hwRevision)
> > return -ENODEV;
> > }
> >
> > + /* Construct our Algorithms */
> > + algorithms_.push_back(std::make_unique<algorithms::Agc>());
> > +
> > return 0;
> > }
> >
> > @@ -183,6 +186,26 @@ int IPARkISP1::configure([[maybe_unused]] const IPACameraSensorInfo &info,
> > /* Set the hardware revision for the algorithms. */
> > context_.configuration.hw.revision = hwRevision_;
> >
> > + context_.configuration.agc.lineDuration = info.lineLength * 1.0s / info.pixelRate;
> > +
> > + /*
> > + * When the AGC computes the new exposure values for a frame, it needs
> > + * to know the limits for shutter speed and analogue gain.
> > + * As it depends on the sensor, update it with the controls.
> > + *
> > + * \todo take VBLANK into account for maximum shutter speed
> > + */
> > + context_.configuration.agc.minShutterSpeed = minExposure_ * context_.configuration.agc.lineDuration;
> > + context_.configuration.agc.maxShutterSpeed = maxExposure_ * context_.configuration.agc.lineDuration;
> > + context_.configuration.agc.minAnalogueGain = camHelper_->gain(minGain_);
> > + context_.configuration.agc.maxAnalogueGain = camHelper_->gain(maxGain_);
> > +
> > + for (auto const &algo : algorithms_) {
> > + int ret = algo->configure(context_, info);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > return 0;
> > }
> >
> > @@ -227,6 +250,9 @@ void IPARkISP1::processEvent(const RkISP1Event &event)
> > reinterpret_cast<rkisp1_stat_buffer *>(
> > mappedBuffers_.at(bufferId).planes()[0].data());
> >
> > + context_.frameContext.sensor.exposure = event.sensorControls.get(V4L2_CID_EXPOSURE).get<int32_t>();
> > + context_.frameContext.sensor.gain = camHelper_->gain(event.sensorControls.get(V4L2_CID_ANALOGUE_GAIN).get<int32_t>());
Shorter lines would be good.
> > +
> > updateStatistics(frame, stats);
> > break;
> > }
> > @@ -271,44 +297,12 @@ void IPARkISP1::queueRequest(unsigned int frame, rkisp1_params_cfg *params,
> > void IPARkISP1::updateStatistics(unsigned int frame,
> > const rkisp1_stat_buffer *stats)
> > {
> > - const rkisp1_cif_isp_stat *params = &stats->params;
> > unsigned int aeState = 0;
> >
> > - if (stats->meas_type & RKISP1_CIF_ISP_STAT_AUTOEXP) {
> > - const rkisp1_cif_isp_ae_stat *ae = ¶ms->ae;
> > -
> > - const unsigned int target = 60;
> > -
> > - unsigned int value = 0;
> > - unsigned int num = 0;
> > - for (unsigned int i = 0; i < hwAeMeanMax_; i++) {
> > - if (ae->exp_mean[i] <= 15)
> > - continue;
> > -
> > - value += ae->exp_mean[i];
> > - num++;
> > - }
> > - value /= num;
> > + for (auto const &algo : algorithms_)
> > + algo->process(context_, stats);
> >
> > - double factor = (double)target / value;
> > -
> > - if (frame % 3 == 0) {
> > - double exposure;
> > -
> > - exposure = factor * exposure_ * gain_ / minGain_;
> > - exposure_ = std::clamp<uint64_t>((uint64_t)exposure,
> > - minExposure_,
> > - maxExposure_);
> > -
> > - exposure = exposure / exposure_ * minGain_;
> > - gain_ = std::clamp<uint64_t>((uint64_t)exposure,
> > - minGain_, maxGain_);
> > -
> > - setControls(frame + 1);
> > - }
> > -
> > - aeState = fabs(factor - 1.0f) < 0.05f ? 2 : 1;
> > - }
> > + setControls(frame);
> >
> > metadataReady(frame, aeState);
> > }
> > @@ -318,6 +312,9 @@ void IPARkISP1::setControls(unsigned int frame)
> > RkISP1Action op;
> > op.op = ActionV4L2Set;
> >
> > + exposure_ = context_.frameContext.agc.exposure;
> > + gain_ = camHelper_->gainCode(context_.frameContext.agc.gain);
I think these can become local variables.
> > +
> > ControlList ctrls(ctrls_);
> > ctrls.set(V4L2_CID_EXPOSURE, static_cast<int32_t>(exposure_));
> > ctrls.set(V4L2_CID_ANALOGUE_GAIN, static_cast<int32_t>(gain_));
--
Regards,
Laurent Pinchart
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