[PATCH v2 5/8] ipa: ipu3: Derive ipu3::algorithms::Agc from MeanLuminanceAgc
Dan Scally
dan.scally at ideasonboard.com
Wed Apr 24 11:00:37 CEST 2024
Hi Stefan
On 18/04/2024 08:56, Stefan Klug wrote:
> Hi Daniel,
>
> thanks for the patch.
>
> On Wed, Apr 17, 2024 at 02:15:33PM +0100, Daniel Scally wrote:
>> In preparation for switching to a derivation of MeanLuminanceAgc, add
>> a function to parse and store the statistics for easy retrieval in an
>> overriding estimateLuminance() function.
>>
>> Now that we have a MeanLuminanceAgc class that centralises our AEGC
>> algorithm, derive the IPU3's Agc class from it and plumb in the
>> necessary framework to enable it to be used. For simplicity's sake
>> this commit switches the algorithm to use the derived class, but
>> does not remove the bespoke functions at this time.
>>
>> Signed-off-by: Daniel Scally <dan.scally at ideasonboard.com>
>> ---
>> Changes in v2:
>>
>> - Squashed the patch adding parseStatistics()
>> - Used the first available constraint and exposure modes rather than
>> assuming the "Normal" mode was available
>> - Used a vector of RGB tuples in estimateLuminance() rather than 3
>> vectors
>> - Stored a copy of the bdsGrid and AWB gains rather than a pointer to
>> the context for use in estimateLuminance()
>> - Remembered to report the controls out to IPAIPU3::updateControls()
>>
>> src/ipa/ipu3/algorithms/agc.cpp | 120 ++++++++++++++++++++++++++++++--
>> src/ipa/ipu3/algorithms/agc.h | 14 +++-
>> src/ipa/ipu3/ipa_context.cpp | 3 +
>> src/ipa/ipu3/ipa_context.h | 5 ++
>> src/ipa/ipu3/ipu3.cpp | 3 +-
>> 5 files changed, 136 insertions(+), 9 deletions(-)
>>
>> diff --git a/src/ipa/ipu3/algorithms/agc.cpp b/src/ipa/ipu3/algorithms/agc.cpp
>> index 606a237a..3b9761bd 100644
>> --- a/src/ipa/ipu3/algorithms/agc.cpp
>> +++ b/src/ipa/ipu3/algorithms/agc.cpp
>> @@ -71,11 +71,33 @@ static constexpr uint32_t kNumStartupFrames = 10;
>> static constexpr double kRelativeLuminanceTarget = 0.16;
>>
>> Agc::Agc()
>> - : frameCount_(0), minShutterSpeed_(0s),
>> - maxShutterSpeed_(0s), filteredExposure_(0s)
>> + : minShutterSpeed_(0s), maxShutterSpeed_(0s)
>> {
>> }
>>
>> +/**
>> + * \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;
>> +
>> + context.ctrlMap.merge(controls());
>> +
>> + return 0;
>> +}
>> +
>> /**
>> * \brief Configure the AGC given a configInfo
>> * \param[in] context The shared IPA context
>> @@ -90,6 +112,7 @@ int Agc::configure(IPAContext &context,
>> IPAActiveState &activeState = context.activeState;
>>
>> stride_ = configuration.grid.stride;
>> + bdsGrid_ = configuration.grid.bdsGrid;
>>
>> minShutterSpeed_ = configuration.agc.minShutterSpeed;
>> maxShutterSpeed_ = std::min(configuration.agc.maxShutterSpeed,
>> @@ -103,6 +126,16 @@ int Agc::configure(IPAContext &context,
>> activeState.agc.exposure = 10ms / configuration.sensor.lineDuration;
>>
>> frameCount_ = 0;
> IMHO That line can be removed as you call resetFrameCount() below.
This is actually libcamera::ipa::ipu3::algorithms::Agc::frameCount_ rather than
libcamera::ipa::AgcMeanLuminance::frameCount_, which is what resetFrameCount() touches. It's removed
along with the rest of the bespoke implementation in the next patch...does it still need to be
removed here?
>
> With that fixed
> Reviewed-by: Stefan Klug <stefan.klug at ideasonboard.com>
Thanks!
>
> Cheers,
> Stefan
>
>> +
>> + context.activeState.agc.constraintMode = constraintModes().begin()->first;
>> + context.activeState.agc.exposureMode = exposureModeHelpers().begin()->first;
>> +
>> + /* \todo Run this again when FrameDurationLimits is passed in */
>> + configureExposureModeHelpers(minShutterSpeed_, maxShutterSpeed_,
>> + minAnalogueGain_, maxAnalogueGain_);
>> +
>> + resetFrameCount();
>> +
>> return 0;
>> }
>>
>> @@ -142,6 +175,39 @@ double Agc::measureBrightness(const ipu3_uapi_stats_3a *stats,
>> return Histogram(Span<uint32_t>(hist)).interQuantileMean(0.98, 1.0);
>> }
>>
>> +Histogram Agc::parseStatistics(const ipu3_uapi_stats_3a *stats,
>> + const ipu3_uapi_grid_config &grid)
>> +{
>> + uint32_t hist[knumHistogramBins] = { 0 };
>> +
>> + rgbTriples_.clear();
>> +
>> + for (unsigned int cellY = 0; cellY < grid.height; cellY++) {
>> + for (unsigned int cellX = 0; cellX < grid.width; cellX++) {
>> + uint32_t cellPosition = cellY * stride_ + cellX;
>> +
>> + const ipu3_uapi_awb_set_item *cell =
>> + reinterpret_cast<const ipu3_uapi_awb_set_item *>(
>> + &stats->awb_raw_buffer.meta_data[cellPosition]);
>> +
>> + rgbTriples_.push_back({
>> + cell->R_avg,
>> + (cell->Gr_avg + cell->Gb_avg) / 2,
>> + cell->B_avg
>> + });
>> +
>> + /*
>> + * Store the average green value to estimate the
>> + * brightness. Even the overexposed pixels are
>> + * taken into account.
>> + */
>> + hist[(cell->Gr_avg + cell->Gb_avg) / 2]++;
>> + }
>> + }
>> +
>> + return Histogram(Span<uint32_t>(hist));
>> +}
>> +
>> /**
>> * \brief Apply a filter on the exposure value to limit the speed of changes
>> * \param[in] exposureValue The target exposure from the AGC algorithm
>> @@ -247,11 +313,6 @@ void Agc::computeExposure(IPAContext &context, IPAFrameContext &frameContext,
>> LOG(IPU3Agc, Debug) << "Divided up shutter and gain are "
>> << shutterTime << " and "
>> << stepGain;
>> -
>> - IPAActiveState &activeState = context.activeState;
>> - /* Update the estimated exposure and gain. */
>> - activeState.agc.exposure = shutterTime / configuration.sensor.lineDuration;
>> - activeState.agc.gain = stepGain;
>> }
>>
>> /**
>> @@ -314,6 +375,23 @@ double Agc::estimateLuminance(IPAActiveState &activeState,
>> return ySum / (grid.height * grid.width) / 255;
>> }
>>
>> +double Agc::estimateLuminance(double gain)
>> +{
>> + double redSum = 0, greenSum = 0, blueSum = 0;
>> +
>> + for (unsigned int i = 0; i < rgbTriples_.size(); i++) {
>> + redSum += std::min(std::get<0>(rgbTriples_[i]) * gain, 255.0);
>> + greenSum += std::min(std::get<1>(rgbTriples_[i]) * gain, 255.0);
>> + blueSum += std::min(std::get<2>(rgbTriples_[i]) * gain, 255.0);
>> + }
>> +
>> + double ySum = redSum * rGain_ * 0.299
>> + + greenSum * gGain_ * 0.587
>> + + blueSum * bGain_ * 0.114;
>> +
>> + return ySum / (bdsGrid_.height * bdsGrid_.width) / 255;
>> +}
>> +
>> /**
>> * \brief Process IPU3 statistics, and run AGC operations
>> * \param[in] context The shared IPA context
>> @@ -366,8 +444,36 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
>> computeExposure(context, frameContext, yGain, iqMeanGain);
>> frameCount_++;
>>
>> + Histogram hist = parseStatistics(stats, context.configuration.grid.bdsGrid);
>> + rGain_ = context.activeState.awb.gains.red;
>> + gGain_ = context.activeState.awb.gains.blue;
>> + bGain_ = context.activeState.awb.gains.green;
>> +
>> + /*
>> + * The Agc algorithm needs to know the effective exposure value that was
>> + * applied to the sensor when the statistics were collected.
>> + */
>> utils::Duration exposureTime = context.configuration.sensor.lineDuration
>> * frameContext.sensor.exposure;
>> + double analogueGain = frameContext.sensor.gain;
>> + utils::Duration effectiveExposureValue = exposureTime * analogueGain;
>> +
>> + utils::Duration shutterTime;
>> + double aGain, dGain;
>> + std::tie(shutterTime, aGain, dGain) =
>> + calculateNewEv(context.activeState.agc.constraintMode,
>> + context.activeState.agc.exposureMode, hist,
>> + effectiveExposureValue);
>> +
>> + LOG(IPU3Agc, 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.exposure = shutterTime / context.configuration.sensor.lineDuration;
>> + activeState.agc.gain = aGain;
>> +
>> metadata.set(controls::AnalogueGain, frameContext.sensor.gain);
>> metadata.set(controls::ExposureTime, exposureTime.get<std::micro>());
>>
>> diff --git a/src/ipa/ipu3/algorithms/agc.h b/src/ipa/ipu3/algorithms/agc.h
>> index 9d6e3ff1..40f32188 100644
>> --- a/src/ipa/ipu3/algorithms/agc.h
>> +++ b/src/ipa/ipu3/algorithms/agc.h
>> @@ -13,6 +13,9 @@
>>
>> #include <libcamera/geometry.h>
>>
>> +#include "libipa/agc_mean_luminance.h"
>> +#include "libipa/histogram.h"
>> +
>> #include "algorithm.h"
>>
>> namespace libcamera {
>> @@ -21,12 +24,13 @@ struct IPACameraSensorInfo;
>>
>> namespace ipa::ipu3::algorithms {
>>
>> -class Agc : public Algorithm
>> +class Agc : public Algorithm, public AgcMeanLuminance
>> {
>> public:
>> Agc();
>> ~Agc() = default;
>>
>> + int init(IPAContext &context, const YamlObject &tuningData) override;
>> int configure(IPAContext &context, const IPAConfigInfo &configInfo) override;
>> void process(IPAContext &context, const uint32_t frame,
>> IPAFrameContext &frameContext,
>> @@ -43,6 +47,9 @@ private:
>> const ipu3_uapi_grid_config &grid,
>> const ipu3_uapi_stats_3a *stats,
>> double gain);
>> + double estimateLuminance(double gain) override;
>> + Histogram parseStatistics(const ipu3_uapi_stats_3a *stats,
>> + const ipu3_uapi_grid_config &grid);
>>
>> uint64_t frameCount_;
>>
>> @@ -55,6 +62,11 @@ private:
>> utils::Duration filteredExposure_;
>>
>> uint32_t stride_;
>> + double rGain_;
>> + double gGain_;
>> + double bGain_;
>> + ipu3_uapi_grid_config bdsGrid_;
>> + std::vector<std::tuple<uint8_t, uint8_t, uint8_t>> rgbTriples_;
>> };
>>
>> } /* namespace ipa::ipu3::algorithms */
>> diff --git a/src/ipa/ipu3/ipa_context.cpp b/src/ipa/ipu3/ipa_context.cpp
>> index 959f314f..c4fb5642 100644
>> --- a/src/ipa/ipu3/ipa_context.cpp
>> +++ b/src/ipa/ipu3/ipa_context.cpp
>> @@ -47,6 +47,9 @@ namespace libcamera::ipa::ipu3 {
>> *
>> * \var IPAContext::activeState
>> * \brief The current state of IPA algorithms
>> + *
>> + * \var IPAContext::ctrlMap
>> + * \brief A ControlInfoMap::Map of controls populated by the algorithms
>> */
>>
>> /**
>> diff --git a/src/ipa/ipu3/ipa_context.h b/src/ipa/ipu3/ipa_context.h
>> index e9a3863b..a92cb6ce 100644
>> --- a/src/ipa/ipu3/ipa_context.h
>> +++ b/src/ipa/ipu3/ipa_context.h
>> @@ -12,6 +12,7 @@
>>
>> #include <libcamera/base/utils.h>
>>
>> +#include <libcamera/controls.h>
>> #include <libcamera/geometry.h>
>>
>> #include <libipa/fc_queue.h>
>> @@ -55,6 +56,8 @@ struct IPAActiveState {
>> struct {
>> uint32_t exposure;
>> double gain;
>> + uint32_t constraintMode;
>> + uint32_t exposureMode;
>> } agc;
>>
>> struct {
>> @@ -85,6 +88,8 @@ struct IPAContext {
>> IPAActiveState activeState;
>>
>> FCQueue<IPAFrameContext> frameContexts;
>> +
>> + ControlInfoMap::Map ctrlMap;
>> };
>>
>> } /* namespace ipa::ipu3 */
>> diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp
>> index 08ee6eb3..4809eb60 100644
>> --- a/src/ipa/ipu3/ipu3.cpp
>> +++ b/src/ipa/ipu3/ipu3.cpp
>> @@ -189,7 +189,7 @@ private:
>> };
>>
>> IPAIPU3::IPAIPU3()
>> - : context_({ {}, {}, { kMaxFrameContexts } })
>> + : context_({ {}, {}, { kMaxFrameContexts }, {} })
>> {
>> }
>>
>> @@ -287,6 +287,7 @@ void IPAIPU3::updateControls(const IPACameraSensorInfo &sensorInfo,
>> frameDurations[1],
>> frameDurations[2]);
>>
>> + controls.merge(context_.ctrlMap);
>> *ipaControls = ControlInfoMap(std::move(controls), controls::controls);
>> }
>>
>> --
>> 2.34.1
>>
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