[PATCH v2 5/8] ipa: ipu3: Derive ipu3::algorithms::Agc from MeanLuminanceAgc
Stefan Klug
stefan.klug at ideasonboard.com
Thu Apr 18 09:56:37 CEST 2024
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.
With that fixed
Reviewed-by: Stefan Klug <stefan.klug at ideasonboard.com>
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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