[PATCH v2] libcamera: Rename "shutter speed" to "exposure time"
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Tue Nov 26 12:44:53 CET 2024
On Tue, Nov 26, 2024 at 10:01:31AM +0000, Naushir Patuck wrote:
> On Wed, 20 Nov 2024 at 10:38, Laurent Pinchart wrote:
> >
> > The terms "shutter" and "shutter speed" are used through libcamera to
> > mean "exposure time". This is confusing, both due to "speed" being used
> > as "time" while it should be the inverse (i.e. a maximum speed should
> > correspond to the minimum time), and due to "shutter speed" and
> > "exposure time" being used in different places with the same meaning.
> >
> > To improve clarity of the code base and the documentation, use "exposure
> > time" consistently to replace "shutter speed".
> >
> > This rename highlighted another vocabulary issue in libcamera. The
> > ExposureModeHelper::splitExposure() function used to document that it
> > splits "exposure time into shutter time and gain". It has been reworded
> > to "split exposure into exposure time and gain". That is not entirely
> > satisfactory, as "exposure" has a defined meaning in photography (see
> > https://en.wikipedia.org/wiki/Exposure_(photography)) that is not
> > expressed as a duration. This issue if left to be addressed separately.
> >
> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
>
> This all looks reasonable to me. My only concern was possible changes
> to the tuning file keys, but those remain unchanged.
I remembered the request to not change tuning files, so I didn't touch
them.
If you ever, in the future, decide to make backward-incompatible changes
to the tuning files, you could consider renaming this at the same time.
> Reviewed-by: Naushir Patuck <naush at raspberrypi.com>
>
> > ---
> > Changes since v1:
> >
> > - Rename occurrences in the Raspberry Pi IPA module
> > - Rename occurrences in rkisp1 tuning data format
> > ---
> > include/libcamera/ipa/raspberrypi.mojom | 2 +-
> > src/ipa/ipu3/algorithms/agc.cpp | 26 +--
> > src/ipa/ipu3/algorithms/agc.h | 4 +-
> > src/ipa/ipu3/ipa_context.cpp | 8 +-
> > src/ipa/ipu3/ipa_context.h | 4 +-
> > src/ipa/ipu3/ipu3.cpp | 10 +-
> > src/ipa/libipa/agc_mean_luminance.cpp | 53 ++---
> > src/ipa/libipa/agc_mean_luminance.h | 2 +-
> > src/ipa/libipa/exposure_mode_helper.cpp | 152 +++++++--------
> > src/ipa/libipa/exposure_mode_helper.h | 14 +-
> > src/ipa/rkisp1/algorithms/agc.cpp | 27 +--
> > src/ipa/rkisp1/ipa_context.cpp | 8 +-
> > src/ipa/rkisp1/ipa_context.h | 4 +-
> > src/ipa/rkisp1/rkisp1.cpp | 10 +-
> > src/ipa/rpi/cam_helper/cam_helper.cpp | 2 +-
> > src/ipa/rpi/cam_helper/cam_helper_imx219.cpp | 2 +-
> > src/ipa/rpi/cam_helper/cam_helper_imx477.cpp | 4 +-
> > src/ipa/rpi/cam_helper/cam_helper_imx519.cpp | 4 +-
> > src/ipa/rpi/cam_helper/cam_helper_imx708.cpp | 4 +-
> > src/ipa/rpi/common/ipa_base.cpp | 46 +++--
> > src/ipa/rpi/controller/agc_algorithm.h | 6 +-
> > src/ipa/rpi/controller/agc_status.h | 4 +-
> > src/ipa/rpi/controller/camera_mode.h | 6 +-
> > src/ipa/rpi/controller/device_status.cpp | 2 +-
> > src/ipa/rpi/controller/device_status.h | 8 +-
> > src/ipa/rpi/controller/rpi/agc.cpp | 10 +-
> > src/ipa/rpi/controller/rpi/agc.h | 6 +-
> > src/ipa/rpi/controller/rpi/agc_channel.cpp | 191 ++++++++++---------
> > src/ipa/rpi/controller/rpi/agc_channel.h | 14 +-
> > src/ipa/rpi/controller/rpi/lux.cpp | 8 +-
> > src/ipa/rpi/controller/rpi/lux.h | 2 +-
> > src/libcamera/control_ids_core.yaml | 14 +-
> > utils/tuning/libtuning/modules/agc/rkisp1.py | 4 +-
> > 33 files changed, 334 insertions(+), 327 deletions(-)
> >
> > diff --git a/include/libcamera/ipa/raspberrypi.mojom b/include/libcamera/ipa/raspberrypi.mojom
> > index 5986c4366c15..0b92587de1be 100644
> > --- a/include/libcamera/ipa/raspberrypi.mojom
> > +++ b/include/libcamera/ipa/raspberrypi.mojom
> > @@ -272,7 +272,7 @@ interface IPARPiEventInterface {
> > * \param[in] delayContext IPA context index used for this request
> > *
> > * This asynchronous event is signalled to the pipeline handler when
> > - * the IPA requires sensor specific controls (e.g. shutter speed, gain,
> > + * the IPA requires sensor specific controls (e.g. exposure time, gain,
> > * blanking) to be applied.
> > */
> > setDelayedControls(libcamera.ControlList controls, uint32 delayContext);
> > diff --git a/src/ipa/ipu3/algorithms/agc.cpp b/src/ipa/ipu3/algorithms/agc.cpp
> > index 466b3fb31a6c..466692036824 100644
> > --- a/src/ipa/ipu3/algorithms/agc.cpp
> > +++ b/src/ipa/ipu3/algorithms/agc.cpp
> > @@ -34,7 +34,7 @@ namespace ipa::ipu3::algorithms {
> > * \class Agc
> > * \brief A mean-based auto-exposure algorithm
> > *
> > - * This algorithm calculates a shutter time and an analogue gain so that the
> > + * This algorithm calculates an exposure time and an analogue gain so that the
> > * average value of the green channel of the brightest 2% of pixels approaches
> > * 0.5. The AWB gains are not used here, and all cells in the grid have the same
> > * weight, like an average-metering case. In this metering mode, the camera uses
> > @@ -52,13 +52,13 @@ LOG_DEFINE_CATEGORY(IPU3Agc)
> > static constexpr double kMinAnalogueGain = 1.0;
> >
> > /* \todo Honour the FrameDurationLimits control instead of hardcoding a limit */
> > -static constexpr utils::Duration kMaxShutterSpeed = 60ms;
> > +static constexpr utils::Duration kMaxExposureTime = 60ms;
> >
> > /* Histogram constants */
> > static constexpr uint32_t knumHistogramBins = 256;
> >
> > Agc::Agc()
> > - : minShutterSpeed_(0s), maxShutterSpeed_(0s)
> > + : minExposureTime_(0s), maxExposureTime_(0s)
> > {
> > }
> >
> > @@ -101,9 +101,9 @@ int Agc::configure(IPAContext &context,
> > stride_ = configuration.grid.stride;
> > bdsGrid_ = configuration.grid.bdsGrid;
> >
> > - minShutterSpeed_ = configuration.agc.minShutterSpeed;
> > - maxShutterSpeed_ = std::min(configuration.agc.maxShutterSpeed,
> > - kMaxShutterSpeed);
> > + minExposureTime_ = configuration.agc.minExposureTime;
> > + maxExposureTime_ = std::min(configuration.agc.maxExposureTime,
> > + kMaxExposureTime);
> >
> > minAnalogueGain_ = std::max(configuration.agc.minAnalogueGain, kMinAnalogueGain);
> > maxAnalogueGain_ = configuration.agc.maxAnalogueGain;
> > @@ -116,7 +116,7 @@ int Agc::configure(IPAContext &context,
> > context.activeState.agc.exposureMode = exposureModeHelpers().begin()->first;
> >
> > /* \todo Run this again when FrameDurationLimits is passed in */
> > - setLimits(minShutterSpeed_, maxShutterSpeed_, minAnalogueGain_,
> > + setLimits(minExposureTime_, maxExposureTime_, minAnalogueGain_,
> > maxAnalogueGain_);
> > resetFrameCount();
> >
> > @@ -223,20 +223,20 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
> > double analogueGain = frameContext.sensor.gain;
> > utils::Duration effectiveExposureValue = exposureTime * analogueGain;
> >
> > - utils::Duration shutterTime;
> > + utils::Duration newExposureTime;
> > double aGain, dGain;
> > - std::tie(shutterTime, aGain, dGain) =
> > + std::tie(newExposureTime, 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;
> > + << "Divided up exposure time, analogue gain and digital gain are "
> > + << newExposureTime << ", " << aGain << " and " << dGain;
> >
> > IPAActiveState &activeState = context.activeState;
> > - /* Update the estimated exposure and gain. */
> > - activeState.agc.exposure = shutterTime / context.configuration.sensor.lineDuration;
> > + /* Update the estimated exposure time and gain. */
> > + activeState.agc.exposure = newExposureTime / context.configuration.sensor.lineDuration;
> > activeState.agc.gain = aGain;
> >
> > metadata.set(controls::AnalogueGain, frameContext.sensor.gain);
> > diff --git a/src/ipa/ipu3/algorithms/agc.h b/src/ipa/ipu3/algorithms/agc.h
> > index 411f4da0704e..890c271b4462 100644
> > --- a/src/ipa/ipu3/algorithms/agc.h
> > +++ b/src/ipa/ipu3/algorithms/agc.h
> > @@ -42,8 +42,8 @@ private:
> > Histogram parseStatistics(const ipu3_uapi_stats_3a *stats,
> > const ipu3_uapi_grid_config &grid);
> >
> > - utils::Duration minShutterSpeed_;
> > - utils::Duration maxShutterSpeed_;
> > + utils::Duration minExposureTime_;
> > + utils::Duration maxExposureTime_;
> >
> > double minAnalogueGain_;
> > double maxAnalogueGain_;
> > diff --git a/src/ipa/ipu3/ipa_context.cpp b/src/ipa/ipu3/ipa_context.cpp
> > index 917d06541abe..fe455e0715c6 100644
> > --- a/src/ipa/ipu3/ipa_context.cpp
> > +++ b/src/ipa/ipu3/ipa_context.cpp
> > @@ -92,11 +92,11 @@ namespace libcamera::ipa::ipu3 {
> > * \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.minExposureTime
> > + * \brief Minimum exposure time supported with the configured sensor
> > *
> > - * \var IPASessionConfiguration::agc.maxShutterSpeed
> > - * \brief Maximum shutter speed supported with the configured sensor
> > + * \var IPASessionConfiguration::agc.maxExposureTime
> > + * \brief Maximum exposure time supported with the configured sensor
> > *
> > * \var IPASessionConfiguration::agc.minAnalogueGain
> > * \brief Minimum analogue gain supported with the configured sensor
> > diff --git a/src/ipa/ipu3/ipa_context.h b/src/ipa/ipu3/ipa_context.h
> > index c85d1e34ea85..29f38b36a9a3 100644
> > --- a/src/ipa/ipu3/ipa_context.h
> > +++ b/src/ipa/ipu3/ipa_context.h
> > @@ -33,8 +33,8 @@ struct IPASessionConfiguration {
> > } af;
> >
> > struct {
> > - utils::Duration minShutterSpeed;
> > - utils::Duration maxShutterSpeed;
> > + utils::Duration minExposureTime;
> > + utils::Duration maxExposureTime;
> > double minAnalogueGain;
> > double maxAnalogueGain;
> > } agc;
> > diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp
> > index 89c3192c6295..44c98cbf6e89 100644
> > --- a/src/ipa/ipu3/ipu3.cpp
> > +++ b/src/ipa/ipu3/ipu3.cpp
> > @@ -112,7 +112,7 @@ namespace ipa::ipu3 {
> > * blue gains to apply to generate a neutral grey frame overall.
> > *
> > * AGC is handled by calculating a histogram of the green channel to estimate an
> > - * analogue gain and shutter time which will provide a well exposed frame. A
> > + * analogue gain and exposure time which will provide a well exposed frame. A
> > * low-pass IIR filter is used to smooth the changes to the sensor to reduce
> > * perceivable steps.
> > *
> > @@ -215,13 +215,13 @@ void IPAIPU3::updateSessionConfiguration(const ControlInfoMap &sensorControls)
> >
> > /*
> > * When the AGC computes the new exposure values for a frame, it needs
> > - * to know the limits for shutter speed and analogue gain.
> > + * to know the limits for exposure time and analogue gain.
> > * As it depends on the sensor, update it with the controls.
> > *
> > - * \todo take VBLANK into account for maximum shutter speed
> > + * \todo take VBLANK into account for maximum exposure time
> > */
> > - context_.configuration.agc.minShutterSpeed = minExposure * context_.configuration.sensor.lineDuration;
> > - context_.configuration.agc.maxShutterSpeed = maxExposure * context_.configuration.sensor.lineDuration;
> > + context_.configuration.agc.minExposureTime = minExposure * context_.configuration.sensor.lineDuration;
> > + context_.configuration.agc.maxExposureTime = maxExposure * context_.configuration.sensor.lineDuration;
> > context_.configuration.agc.minAnalogueGain = camHelper_->gain(minGain);
> > context_.configuration.agc.maxAnalogueGain = camHelper_->gain(maxGain);
> > }
> > diff --git a/src/ipa/libipa/agc_mean_luminance.cpp b/src/ipa/libipa/agc_mean_luminance.cpp
> > index f97ef11771c4..cd17570861e9 100644
> > --- a/src/ipa/libipa/agc_mean_luminance.cpp
> > +++ b/src/ipa/libipa/agc_mean_luminance.cpp
> > @@ -89,10 +89,10 @@ static constexpr double kDefaultRelativeLuminanceTarget = 0.16;
> > * \class AgcMeanLuminance
> > * \brief A mean-based auto-exposure algorithm
> > *
> > - * This algorithm calculates a shutter time, analogue and digital gain such that
> > - * the normalised mean luminance value of an image is driven towards a target,
> > - * which itself is discovered from tuning data. The algorithm is a two-stage
> > - * process.
> > + * This algorithm calculates an exposure time, analogue and digital gain such
> > + * that the normalised mean luminance value of an image is driven towards a
> > + * target, which itself is discovered from tuning data. The algorithm is a
> > + * two-stage process.
> > *
> > * In the first stage, an initial gain value is derived by iteratively comparing
> > * the gain-adjusted mean luminance across the entire image against a target,
> > @@ -109,7 +109,7 @@ static constexpr double kDefaultRelativeLuminanceTarget = 0.16;
> > * stage is then clamped to the gain from this stage.
> > *
> > * The final gain is used to adjust the effective exposure value of the image,
> > - * and that new exposure value is divided into shutter time, analogue gain and
> > + * and that new exposure value is divided into exposure time, analogue gain and
> > * digital gain according to the selected AeExposureMode. This class uses the
> > * \ref ExposureModeHelper class to assist in that division, and expects the
> > * data needed to initialise that class to be present in tuning data in a
> > @@ -247,27 +247,27 @@ int AgcMeanLuminance::parseExposureModes(const YamlObject &tuningData)
> > return -EINVAL;
> > }
> >
> > - std::vector<uint32_t> shutters =
> > - modeValues["shutter"].getList<uint32_t>().value_or(std::vector<uint32_t>{});
> > + std::vector<uint32_t> exposureTimes =
> > + modeValues["exposure-time"].getList<uint32_t>().value_or(std::vector<uint32_t>{});
> > std::vector<double> gains =
> > modeValues["gain"].getList<double>().value_or(std::vector<double>{});
> >
> > - if (shutters.size() != gains.size()) {
> > + if (exposureTimes.size() != gains.size()) {
> > LOG(AgcMeanLuminance, Error)
> > - << "Shutter and gain array sizes unequal";
> > + << "Exposure time and gain array sizes unequal";
> > return -EINVAL;
> > }
> >
> > - if (shutters.empty()) {
> > + if (exposureTimes.empty()) {
> > LOG(AgcMeanLuminance, Error)
> > - << "Shutter and gain arrays are empty";
> > + << "Exposure time and gain arrays are empty";
> > return -EINVAL;
> > }
> >
> > std::vector<std::pair<utils::Duration, double>> stages;
> > - for (unsigned int i = 0; i < shutters.size(); i++) {
> > + for (unsigned int i = 0; i < exposureTimes.size(); i++) {
> > stages.push_back({
> > - std::chrono::microseconds(shutters[i]),
> > + std::chrono::microseconds(exposureTimes[i]),
> > gains[i]
> > });
> > }
> > @@ -283,7 +283,7 @@ int AgcMeanLuminance::parseExposureModes(const YamlObject &tuningData)
> > /*
> > * If we don't have any exposure modes in the tuning data we create an
> > * ExposureModeHelper using an empty vector of stages. This will result
> > - * in the ExposureModeHelper simply driving the shutter as high as
> > + * in the ExposureModeHelper simply driving the exposure time as high as
> > * possible before touching gain.
> > */
> > if (availableExposureModes.empty()) {
> > @@ -338,18 +338,18 @@ int AgcMeanLuminance::parseExposureModes(const YamlObject &tuningData)
> > * For the AeExposureMode control the data should contain a dictionary called
> > * AeExposureMode containing per-mode setting dictionaries with the key being a
> > * value from \ref controls::AeExposureModeNameValueMap. Each mode dict should
> > - * contain an array of shutter times with the key "shutter" and an array of gain
> > - * values with the key "gain", in this format:
> > + * contain an array of exposure times with the key "exposure-time" and an array
> > + * of gain values with the key "gain", in this format:
> > *
> > * \code{.unparsed}
> > * algorithms:
> > * - Agc:
> > * AeExposureMode:
> > * ExposureNormal:
> > - * shutter: [ 100, 10000, 30000, 60000, 120000 ]
> > + * exposure-time: [ 100, 10000, 30000, 60000, 120000 ]
> > * gain: [ 2.0, 4.0, 6.0, 8.0, 10.0 ]
> > * ExposureShort:
> > - * shutter: [ 100, 10000, 30000, 60000, 120000 ]
> > + * exposure-time: [ 100, 10000, 30000, 60000, 120000 ]
> > * gain: [ 2.0, 4.0, 6.0, 8.0, 10.0 ]
> > *
> > * \endcode
> > @@ -371,20 +371,20 @@ int AgcMeanLuminance::parseTuningData(const YamlObject &tuningData)
> >
> > /**
> > * \brief Set the ExposureModeHelper limits for this class
> > - * \param[in] minShutter Minimum shutter time to allow
> > - * \param[in] maxShutter Maximum shutter time to allow
> > + * \param[in] minExposureTime Minimum exposure time to allow
> > + * \param[in] maxExposureTime Maximum ewposure time to allow
> > * \param[in] minGain Minimum gain to allow
> > * \param[in] maxGain Maximum gain to allow
> > *
> > * This function calls \ref ExposureModeHelper::setLimits() for each
> > * ExposureModeHelper that has been created for this class.
> > */
> > -void AgcMeanLuminance::setLimits(utils::Duration minShutter,
> > - utils::Duration maxShutter,
> > +void AgcMeanLuminance::setLimits(utils::Duration minExposureTime,
> > + utils::Duration maxExposureTime,
> > double minGain, double maxGain)
> > {
> > for (auto &[id, helper] : exposureModeHelpers_)
> > - helper->setLimits(minShutter, maxShutter, minGain, maxGain);
> > + helper->setLimits(minExposureTime, maxExposureTime, minGain, maxGain);
> > }
> >
> > /**
> > @@ -513,7 +513,8 @@ utils::Duration AgcMeanLuminance::filterExposure(utils::Duration exposureValue)
> > }
> >
> > /**
> > - * \brief Calculate the new exposure value and splut it between shutter time and gain
> > + * \brief Calculate the new exposure value and splut it between exposure time
> > + * and gain
> > * \param[in] constraintModeIndex The index of the current constraint mode
> > * \param[in] exposureModeIndex The index of the current exposure mode
> > * \param[in] yHist A Histogram from the ISP statistics to use in constraining
> > @@ -523,9 +524,9 @@ utils::Duration AgcMeanLuminance::filterExposure(utils::Duration exposureValue)
> > *
> > * Calculate a new exposure value to try to obtain the target. The calculated
> > * exposure value is filtered to prevent rapid changes from frame to frame, and
> > - * divided into shutter time, analogue and digital gain.
> > + * divided into exposure time, analogue and digital gain.
> > *
> > - * \return Tuple of shutter time, analogue gain, and digital gain
> > + * \return Tuple of exposure time, analogue gain, and digital gain
> > */
> > std::tuple<utils::Duration, double, double>
> > AgcMeanLuminance::calculateNewEv(uint32_t constraintModeIndex,
> > diff --git a/src/ipa/libipa/agc_mean_luminance.h b/src/ipa/libipa/agc_mean_luminance.h
> > index 576d28be8eb0..c41391cb0b73 100644
> > --- a/src/ipa/libipa/agc_mean_luminance.h
> > +++ b/src/ipa/libipa/agc_mean_luminance.h
> > @@ -44,7 +44,7 @@ public:
> >
> > int parseTuningData(const YamlObject &tuningData);
> >
> > - void setLimits(utils::Duration minShutter, utils::Duration maxShutter,
> > + void setLimits(utils::Duration minExposureTime, utils::Duration maxExposureTime,
> > double minGain, double maxGain);
> >
> > std::map<int32_t, std::vector<AgcConstraint>> constraintModes()
> > diff --git a/src/ipa/libipa/exposure_mode_helper.cpp b/src/ipa/libipa/exposure_mode_helper.cpp
> > index 30da0c894044..f235316d3539 100644
> > --- a/src/ipa/libipa/exposure_mode_helper.cpp
> > +++ b/src/ipa/libipa/exposure_mode_helper.cpp
> > @@ -14,9 +14,9 @@
> > * \file exposure_mode_helper.h
> > * \brief Helper class that performs computations relating to exposure
> > *
> > - * AEGC algorithms have a need to split exposure between shutter time, analogue
> > + * AEGC algorithms have a need to split exposure between exposure time, analogue
> > * and digital gain. Multiple implementations do so based on paired stages of
> > - * shutter time and gain limits; provide a helper to avoid duplicating the code.
> > + * exposure time and gain limits; provide a helper to avoid duplicating the code.
> > */
> >
> > namespace libcamera {
> > @@ -29,24 +29,24 @@ namespace ipa {
> >
> > /**
> > * \class ExposureModeHelper
> > - * \brief Class for splitting exposure into shutter time and total gain
> > + * \brief Class for splitting exposure into exposure time and total gain
> > *
> > * The ExposureModeHelper class provides a standard interface through which an
> > - * AEGC algorithm can divide exposure between shutter time and gain. It is
> > - * configured with a set of shutter time and gain pairs and works by initially
> > - * fixing gain at 1.0 and increasing shutter time up to the shutter time value
> > + * AEGC algorithm can divide exposure between exposure time and gain. It is
> > + * configured with a set of exposure time and gain pairs and works by initially
> > + * fixing gain at 1.0 and increasing exposure time up to the exposure time value
> > * from the first pair in the set in an attempt to meet the required exposure
> > * value.
> > *
> > - * If the required exposure is not achievable by the first shutter time value
> > + * If the required exposure is not achievable by the first exposure time value
> > * alone it ramps gain up to the value from the first pair in the set. If the
> > - * required exposure is still not met it then allows shutter time to ramp up to
> > - * the shutter time value from the second pair in the set, and continues in this
> > + * required exposure is still not met it then allows exposure time to ramp up to
> > + * the exposure time value from the second pair in the set, and continues in this
> > * vein until either the required exposure time is met, or else the hardware's
> > - * shutter time or gain limits are reached.
> > + * exposure time or gain limits are reached.
> > *
> > * This method allows users to strike a balance between a well-exposed image and
> > - * an acceptable frame-rate, as opposed to simply maximising shutter time
> > + * an acceptable frame-rate, as opposed to simply maximising exposure time
> > * followed by gain. The same helpers can be used to perform the latter
> > * operation if needed by passing an empty set of pairs to the initialisation
> > * function.
> > @@ -61,9 +61,9 @@ namespace ipa {
> >
> > /**
> > * \brief Construct an ExposureModeHelper instance
> > - * \param[in] stages The vector of paired shutter time and gain limits
> > + * \param[in] stages The vector of paired exposure time and gain limits
> > *
> > - * The input stages are shutter time and _total_ gain pairs; the gain
> > + * The input stages are exposure time and _total_ gain pairs; the gain
> > * encompasses both analogue and digital gain.
> > *
> > * The vector of stages may be empty. In that case, the helper will simply use
> > @@ -71,46 +71,46 @@ namespace ipa {
> > */
> > ExposureModeHelper::ExposureModeHelper(const Span<std::pair<utils::Duration, double>> stages)
> > {
> > - minShutter_ = 0us;
> > - maxShutter_ = 0us;
> > + minExposureTime_ = 0us;
> > + maxExposureTime_ = 0us;
> > minGain_ = 0;
> > maxGain_ = 0;
> >
> > for (const auto &[s, g] : stages) {
> > - shutters_.push_back(s);
> > + exposureTimes_.push_back(s);
> > gains_.push_back(g);
> > }
> > }
> >
> > /**
> > - * \brief Set the shutter time and gain limits
> > - * \param[in] minShutter The minimum shutter time supported
> > - * \param[in] maxShutter The maximum shutter time supported
> > + * \brief Set the exposure time and gain limits
> > + * \param[in] minExposureTime The minimum exposure time supported
> > + * \param[in] maxExposureTime The maximum exposure time supported
> > * \param[in] minGain The minimum analogue gain supported
> > * \param[in] maxGain The maximum analogue gain supported
> > *
> > - * This function configures the shutter time and analogue gain limits that need
> > + * This function configures the exposure time and analogue gain limits that need
> > * to be adhered to as the helper divides up exposure. Note that this function
> > * *must* be called whenever those limits change and before splitExposure() is
> > * used.
> > *
> > - * If the algorithm using the helpers needs to indicate that either shutter time
> > + * If the algorithm using the helpers needs to indicate that either exposure time
> > * or analogue gain or both should be fixed it can do so by setting both the
> > * minima and maxima to the same value.
> > */
> > -void ExposureModeHelper::setLimits(utils::Duration minShutter,
> > - utils::Duration maxShutter,
> > +void ExposureModeHelper::setLimits(utils::Duration minExposureTime,
> > + utils::Duration maxExposureTime,
> > double minGain, double maxGain)
> > {
> > - minShutter_ = minShutter;
> > - maxShutter_ = maxShutter;
> > + minExposureTime_ = minExposureTime;
> > + maxExposureTime_ = maxExposureTime;
> > minGain_ = minGain;
> > maxGain_ = maxGain;
> > }
> >
> > -utils::Duration ExposureModeHelper::clampShutter(utils::Duration shutter) const
> > +utils::Duration ExposureModeHelper::clampExposureTime(utils::Duration exposureTime) const
> > {
> > - return std::clamp(shutter, minShutter_, maxShutter_);
> > + return std::clamp(exposureTime, minExposureTime_, maxExposureTime_);
> > }
> >
> > double ExposureModeHelper::clampGain(double gain) const
> > @@ -119,108 +119,108 @@ double ExposureModeHelper::clampGain(double gain) const
> > }
> >
> > /**
> > - * \brief Split exposure time into shutter time and gain
> > - * \param[in] exposure Exposure time
> > + * \brief Split exposure into exposure time and gain
> > + * \param[in] exposure Exposure value
> > *
> > - * This function divides a given exposure time into shutter time, analogue and
> > - * digital gain by iterating through stages of shutter time and gain limits. At
> > - * each stage the current stage's shutter time limit is multiplied by the
> > + * This function divides a given exposure into exposure time, analogue and
> > + * digital gain by iterating through stages of exposure time and gain limits.
> > + * At each stage the current stage's exposure time limit is multiplied by the
> > * previous stage's gain limit (or 1.0 initially) to see if the combination of
> > - * the two can meet the required exposure time. If they cannot then the current
> > - * stage's shutter time limit is multiplied by the same stage's gain limit to
> > + * the two can meet the required exposure. If they cannot then the current
> > + * stage's exposure time limit is multiplied by the same stage's gain limit to
> > * see if that combination can meet the required exposure time. If they cannot
> > * then the function moves to consider the next stage.
> > *
> > - * When a combination of shutter time and gain _stage_ limits are found that are
> > - * sufficient to meet the required exposure time, the function attempts to
> > - * reduce shutter time as much as possible whilst fixing gain and still meeting
> > - * the exposure time. If a _runtime_ limit prevents shutter time from being
> > - * lowered enough to meet the exposure time with gain fixed at the stage limit,
> > - * gain is also lowered to compensate.
> > + * When a combination of exposure time and gain _stage_ limits are found that
> > + * are sufficient to meet the required exposure, the function attempts to reduce
> > + * exposure time as much as possible whilst fixing gain and still meeting the
> > + * exposure. If a _runtime_ limit prevents exposure time from being lowered
> > + * enough to meet the exposure with gain fixed at the stage limit, gain is also
> > + * lowered to compensate.
> > *
> > - * Once the shutter time and gain values are ascertained, gain is assigned as
> > + * Once the exposure time and gain values are ascertained, gain is assigned as
> > * analogue gain as much as possible, with digital gain only in use if the
> > * maximum analogue gain runtime limit is unable to accommodate the exposure
> > * value.
> > *
> > - * If no combination of shutter time and gain limits is found that meets the
> > - * required exposure time, the helper falls-back to simply maximising the
> > - * shutter time first, followed by analogue gain, followed by digital gain.
> > + * If no combination of exposure time and gain limits is found that meets the
> > + * required exposure, the helper falls-back to simply maximising the exposure
> > + * time first, followed by analogue gain, followed by digital gain.
> > *
> > - * \return Tuple of shutter time, analogue gain, and digital gain
> > + * \return Tuple of exposure time, analogue gain, and digital gain
> > */
> > std::tuple<utils::Duration, double, double>
> > ExposureModeHelper::splitExposure(utils::Duration exposure) const
> > {
> > - ASSERT(maxShutter_);
> > + ASSERT(maxExposureTime_);
> > ASSERT(maxGain_);
> >
> > bool gainFixed = minGain_ == maxGain_;
> > - bool shutterFixed = minShutter_ == maxShutter_;
> > + bool exposureTimeFixed = minExposureTime_ == maxExposureTime_;
> >
> > /*
> > * There's no point entering the loop if we cannot change either gain
> > - * nor shutter anyway.
> > + * nor exposure time anyway.
> > */
> > - if (shutterFixed && gainFixed)
> > - return { minShutter_, minGain_, exposure / (minShutter_ * minGain_) };
> > + if (exposureTimeFixed && gainFixed)
> > + return { minExposureTime_, minGain_, exposure / (minExposureTime_ * minGain_) };
> >
> > - utils::Duration shutter;
> > + utils::Duration exposureTime;
> > double stageGain = 1.0;
> > double gain;
> >
> > for (unsigned int stage = 0; stage < gains_.size(); stage++) {
> > double lastStageGain = stage == 0 ? 1.0 : clampGain(gains_[stage - 1]);
> > - utils::Duration stageShutter = clampShutter(shutters_[stage]);
> > + utils::Duration stageExposureTime = clampExposureTime(exposureTimes_[stage]);
> > stageGain = clampGain(gains_[stage]);
> >
> > /*
> > - * We perform the clamping on both shutter and gain in case the
> > - * helper has had limits set that prevent those values being
> > - * lowered beyond a certain minimum...this can happen at runtime
> > - * for various reasons and so would not be known when the stage
> > - * limits are initialised.
> > + * We perform the clamping on both exposure time and gain in
> > + * case the helper has had limits set that prevent those values
> > + * being lowered beyond a certain minimum...this can happen at
> > + * runtime for various reasons and so would not be known when
> > + * the stage limits are initialised.
> > */
> >
> > - if (stageShutter * lastStageGain >= exposure) {
> > - shutter = clampShutter(exposure / clampGain(lastStageGain));
> > - gain = clampGain(exposure / shutter);
> > + if (stageExposureTime * lastStageGain >= exposure) {
> > + exposureTime = clampExposureTime(exposure / clampGain(lastStageGain));
> > + gain = clampGain(exposure / exposureTime);
> >
> > - return { shutter, gain, exposure / (shutter * gain) };
> > + return { exposureTime, gain, exposure / (exposureTime * gain) };
> > }
> >
> > - if (stageShutter * stageGain >= exposure) {
> > - shutter = clampShutter(exposure / clampGain(stageGain));
> > - gain = clampGain(exposure / shutter);
> > + if (stageExposureTime * stageGain >= exposure) {
> > + exposureTime = clampExposureTime(exposure / clampGain(stageGain));
> > + gain = clampGain(exposure / exposureTime);
> >
> > - return { shutter, gain, exposure / (shutter * gain) };
> > + return { exposureTime, gain, exposure / (exposureTime * gain) };
> > }
> > }
> >
> > /*
> > - * From here on all we can do is max out the shutter time, followed by
> > + * From here on all we can do is max out the exposure time, followed by
> > * the analogue gain. If we still haven't achieved the target we send
> > * the rest of the exposure time to digital gain. If we were given no
> > * stages to use then the default stageGain of 1.0 is used so that
> > - * shutter time is maxed before gain is touched at all.
> > + * exposure time is maxed before gain is touched at all.
> > */
> > - shutter = clampShutter(exposure / clampGain(stageGain));
> > - gain = clampGain(exposure / shutter);
> > + exposureTime = clampExposureTime(exposure / clampGain(stageGain));
> > + gain = clampGain(exposure / exposureTime);
> >
> > - return { shutter, gain, exposure / (shutter * gain) };
> > + return { exposureTime, gain, exposure / (exposureTime * gain) };
> > }
> >
> > /**
> > - * \fn ExposureModeHelper::minShutter()
> > - * \brief Retrieve the configured minimum shutter time limit set through
> > + * \fn ExposureModeHelper::minExposureTime()
> > + * \brief Retrieve the configured minimum exposure time limit set through
> > * setLimits()
> > - * \return The minShutter_ value
> > + * \return The minExposureTime_ value
> > */
> >
> > /**
> > - * \fn ExposureModeHelper::maxShutter()
> > - * \brief Retrieve the configured maximum shutter time set through setLimits()
> > - * \return The maxShutter_ value
> > + * \fn ExposureModeHelper::maxExposureTime()
> > + * \brief Retrieve the configured maximum exposure time set through setLimits()
> > + * \return The maxExposureTime_ value
> > */
> >
> > /**
> > diff --git a/src/ipa/libipa/exposure_mode_helper.h b/src/ipa/libipa/exposure_mode_helper.h
> > index 85c665d7d187..c5be1b6703a8 100644
> > --- a/src/ipa/libipa/exposure_mode_helper.h
> > +++ b/src/ipa/libipa/exposure_mode_helper.h
> > @@ -24,26 +24,26 @@ public:
> > ExposureModeHelper(const Span<std::pair<utils::Duration, double>> stages);
> > ~ExposureModeHelper() = default;
> >
> > - void setLimits(utils::Duration minShutter, utils::Duration maxShutter,
> > + void setLimits(utils::Duration minExposureTime, utils::Duration maxExposureTime,
> > double minGain, double maxGain);
> >
> > std::tuple<utils::Duration, double, double>
> > splitExposure(utils::Duration exposure) const;
> >
> > - utils::Duration minShutter() const { return minShutter_; }
> > - utils::Duration maxShutter() const { return maxShutter_; }
> > + utils::Duration minExposureTime() const { return minExposureTime_; }
> > + utils::Duration maxExposureTime() const { return maxExposureTime_; }
> > double minGain() const { return minGain_; }
> > double maxGain() const { return maxGain_; }
> >
> > private:
> > - utils::Duration clampShutter(utils::Duration shutter) const;
> > + utils::Duration clampExposureTime(utils::Duration exposureTime) const;
> > double clampGain(double gain) const;
> >
> > - std::vector<utils::Duration> shutters_;
> > + std::vector<utils::Duration> exposureTimes_;
> > std::vector<double> gains_;
> >
> > - utils::Duration minShutter_;
> > - utils::Duration maxShutter_;
> > + utils::Duration minExposureTime_;
> > + utils::Duration maxExposureTime_;
> > double minGain_;
> > double maxGain_;
> > };
> > diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp
> > index 301b7ec26508..40e5a8f481b2 100644
> > --- a/src/ipa/rkisp1/algorithms/agc.cpp
> > +++ b/src/ipa/rkisp1/algorithms/agc.cpp
> > @@ -183,7 +183,7 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo)
> > * 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;
> > + context.activeState.agc.maxFrameDuration = context.configuration.sensor.maxExposureTime;
> >
> > /*
> > * Define the measurement window for AGC as a centered rectangle
> > @@ -194,8 +194,8 @@ 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;
> >
> > - setLimits(context.configuration.sensor.minShutterSpeed,
> > - context.configuration.sensor.maxShutterSpeed,
> > + setLimits(context.configuration.sensor.minExposureTime,
> > + context.configuration.sensor.maxExposureTime,
> > context.configuration.sensor.minAnalogueGain,
> > context.configuration.sensor.maxAnalogueGain);
> >
> > @@ -424,12 +424,12 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
> > [](uint32_t x) { return x >> 4; });
> > expMeans_ = { params->ae.exp_mean, context.hw->numAeCells };
> >
> > - utils::Duration maxShutterSpeed =
> > + utils::Duration maxExposureTime =
> > std::clamp(frameContext.agc.maxFrameDuration,
> > - context.configuration.sensor.minShutterSpeed,
> > - context.configuration.sensor.maxShutterSpeed);
> > - setLimits(context.configuration.sensor.minShutterSpeed,
> > - maxShutterSpeed,
> > + context.configuration.sensor.minExposureTime,
> > + context.configuration.sensor.maxExposureTime);
> > + setLimits(context.configuration.sensor.minExposureTime,
> > + maxExposureTime,
> > context.configuration.sensor.minAnalogueGain,
> > context.configuration.sensor.maxAnalogueGain);
> >
> > @@ -442,20 +442,21 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame,
> > double analogueGain = frameContext.sensor.gain;
> > utils::Duration effectiveExposureValue = exposureTime * analogueGain;
> >
> > - utils::Duration shutterTime;
> > + utils::Duration newExposureTime;
> > double aGain, dGain;
> > - std::tie(shutterTime, aGain, dGain) =
> > + std::tie(newExposureTime, 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;
> > + << "Divided up exposure time, analogue gain and digital gain are "
> > + << newExposureTime << ", " << 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.exposure = newExposureTime
> > + / context.configuration.sensor.lineDuration;
> > activeState.agc.automatic.gain = aGain;
> >
> > fillMetadata(context, frameContext, metadata);
> > diff --git a/src/ipa/rkisp1/ipa_context.cpp b/src/ipa/rkisp1/ipa_context.cpp
> > index 14d0c02a2b32..833e2cbb784f 100644
> > --- a/src/ipa/rkisp1/ipa_context.cpp
> > +++ b/src/ipa/rkisp1/ipa_context.cpp
> > @@ -78,11 +78,11 @@ namespace libcamera::ipa::rkisp1 {
> > * \var IPASessionConfiguration::sensor
> > * \brief Sensor-specific configuration of the IPA
> > *
> > - * \var IPASessionConfiguration::sensor.minShutterSpeed
> > - * \brief Minimum shutter speed supported with the sensor
> > + * \var IPASessionConfiguration::sensor.minExposureTime
> > + * \brief Minimum exposure time supported with the sensor
> > *
> > - * \var IPASessionConfiguration::sensor.maxShutterSpeed
> > - * \brief Maximum shutter speed supported with the sensor
> > + * \var IPASessionConfiguration::sensor.maxExposureTime
> > + * \brief Maximum exposure time supported with the sensor
> > *
> > * \var IPASessionConfiguration::sensor.minAnalogueGain
> > * \brief Minimum analogue gain supported with the sensor
> > diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h
> > index 7b93a9e9461d..0a165c1366f6 100644
> > --- a/src/ipa/rkisp1/ipa_context.h
> > +++ b/src/ipa/rkisp1/ipa_context.h
> > @@ -53,8 +53,8 @@ struct IPASessionConfiguration {
> > } lsc;
> >
> > struct {
> > - utils::Duration minShutterSpeed;
> > - utils::Duration maxShutterSpeed;
> > + utils::Duration minExposureTime;
> > + utils::Duration maxExposureTime;
> > double minAnalogueGain;
> > double maxAnalogueGain;
> >
> > diff --git a/src/ipa/rkisp1/rkisp1.cpp b/src/ipa/rkisp1/rkisp1.cpp
> > index a29dab3403ef..2ffdd99b158a 100644
> > --- a/src/ipa/rkisp1/rkisp1.cpp
> > +++ b/src/ipa/rkisp1/rkisp1.cpp
> > @@ -257,14 +257,14 @@ int IPARkISP1::configure(const IPAConfigInfo &ipaConfig,
> >
> > /*
> > * 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.
> > + * to know the limits for exposure time and analogue gain. As it depends
> > + * on the sensor, update it with the controls.
> > *
> > - * \todo take VBLANK into account for maximum shutter speed
> > + * \todo take VBLANK into account for maximum exposure time
> > */
> > - context_.configuration.sensor.minShutterSpeed =
> > + context_.configuration.sensor.minExposureTime =
> > minExposure * context_.configuration.sensor.lineDuration;
> > - context_.configuration.sensor.maxShutterSpeed =
> > + context_.configuration.sensor.maxExposureTime =
> > maxExposure * context_.configuration.sensor.lineDuration;
> > context_.configuration.sensor.minAnalogueGain =
> > context_.camHelper->gain(minGain);
> > diff --git a/src/ipa/rpi/cam_helper/cam_helper.cpp b/src/ipa/rpi/cam_helper/cam_helper.cpp
> > index ee5d011f1279..6493e88232a4 100644
> > --- a/src/ipa/rpi/cam_helper/cam_helper.cpp
> > +++ b/src/ipa/rpi/cam_helper/cam_helper.cpp
> > @@ -241,7 +241,7 @@ void CamHelper::parseEmbeddedData(Span<const uint8_t> buffer,
> > return;
> > }
> >
> > - deviceStatus.shutterSpeed = parsedDeviceStatus.shutterSpeed;
> > + deviceStatus.exposureTime = parsedDeviceStatus.exposureTime;
> > deviceStatus.analogueGain = parsedDeviceStatus.analogueGain;
> > deviceStatus.frameLength = parsedDeviceStatus.frameLength;
> > deviceStatus.lineLength = parsedDeviceStatus.lineLength;
> > diff --git a/src/ipa/rpi/cam_helper/cam_helper_imx219.cpp b/src/ipa/rpi/cam_helper/cam_helper_imx219.cpp
> > index 91461f7af7b6..ba01153ebecf 100644
> > --- a/src/ipa/rpi/cam_helper/cam_helper_imx219.cpp
> > +++ b/src/ipa/rpi/cam_helper/cam_helper_imx219.cpp
> > @@ -99,7 +99,7 @@ void CamHelperImx219::populateMetadata(const MdParser::RegisterMap ®isters,
> >
> > deviceStatus.lineLength = lineLengthPckToDuration(registers.at(lineLengthHiReg) * 256 +
> > registers.at(lineLengthLoReg));
> > - deviceStatus.shutterSpeed = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > + deviceStatus.exposureTime = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > deviceStatus.lineLength);
> > deviceStatus.analogueGain = gain(registers.at(gainReg));
> > deviceStatus.frameLength = registers.at(frameLengthHiReg) * 256 + registers.at(frameLengthLoReg);
> > diff --git a/src/ipa/rpi/cam_helper/cam_helper_imx477.cpp b/src/ipa/rpi/cam_helper/cam_helper_imx477.cpp
> > index 6bd89334bf50..a53c40cdf843 100644
> > --- a/src/ipa/rpi/cam_helper/cam_helper_imx477.cpp
> > +++ b/src/ipa/rpi/cam_helper/cam_helper_imx477.cpp
> > @@ -112,7 +112,7 @@ void CamHelperImx477::prepare(libcamera::Span<const uint8_t> buffer, Metadata &m
> > DeviceStatus parsedDeviceStatus;
> >
> > metadata.get("device.status", parsedDeviceStatus);
> > - parsedDeviceStatus.shutterSpeed = deviceStatus.shutterSpeed;
> > + parsedDeviceStatus.exposureTime = deviceStatus.exposureTime;
> > parsedDeviceStatus.frameLength = deviceStatus.frameLength;
> > metadata.set("device.status", parsedDeviceStatus);
> >
> > @@ -180,7 +180,7 @@ void CamHelperImx477::populateMetadata(const MdParser::RegisterMap ®isters,
> >
> > deviceStatus.lineLength = lineLengthPckToDuration(registers.at(lineLengthHiReg) * 256 +
> > registers.at(lineLengthLoReg));
> > - deviceStatus.shutterSpeed = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > + deviceStatus.exposureTime = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > deviceStatus.lineLength);
> > deviceStatus.analogueGain = gain(registers.at(gainHiReg) * 256 + registers.at(gainLoReg));
> > deviceStatus.frameLength = registers.at(frameLengthHiReg) * 256 + registers.at(frameLengthLoReg);
> > diff --git a/src/ipa/rpi/cam_helper/cam_helper_imx519.cpp b/src/ipa/rpi/cam_helper/cam_helper_imx519.cpp
> > index c2de3d407d18..2ff086531053 100644
> > --- a/src/ipa/rpi/cam_helper/cam_helper_imx519.cpp
> > +++ b/src/ipa/rpi/cam_helper/cam_helper_imx519.cpp
> > @@ -112,7 +112,7 @@ void CamHelperImx519::prepare(libcamera::Span<const uint8_t> buffer, Metadata &m
> > DeviceStatus parsedDeviceStatus;
> >
> > metadata.get("device.status", parsedDeviceStatus);
> > - parsedDeviceStatus.shutterSpeed = deviceStatus.shutterSpeed;
> > + parsedDeviceStatus.exposureTime = deviceStatus.exposureTime;
> > parsedDeviceStatus.frameLength = deviceStatus.frameLength;
> > metadata.set("device.status", parsedDeviceStatus);
> >
> > @@ -180,7 +180,7 @@ void CamHelperImx519::populateMetadata(const MdParser::RegisterMap ®isters,
> >
> > deviceStatus.lineLength = lineLengthPckToDuration(registers.at(lineLengthHiReg) * 256 +
> > registers.at(lineLengthLoReg));
> > - deviceStatus.shutterSpeed = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > + deviceStatus.exposureTime = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > deviceStatus.lineLength);
> > deviceStatus.analogueGain = gain(registers.at(gainHiReg) * 256 + registers.at(gainLoReg));
> > deviceStatus.frameLength = registers.at(frameLengthHiReg) * 256 + registers.at(frameLengthLoReg);
> > diff --git a/src/ipa/rpi/cam_helper/cam_helper_imx708.cpp b/src/ipa/rpi/cam_helper/cam_helper_imx708.cpp
> > index 63ddb55e6674..ec83d9fdaaf2 100644
> > --- a/src/ipa/rpi/cam_helper/cam_helper_imx708.cpp
> > +++ b/src/ipa/rpi/cam_helper/cam_helper_imx708.cpp
> > @@ -155,7 +155,7 @@ void CamHelperImx708::prepare(libcamera::Span<const uint8_t> buffer, Metadata &m
> > DeviceStatus parsedDeviceStatus;
> >
> > metadata.get("device.status", parsedDeviceStatus);
> > - parsedDeviceStatus.shutterSpeed = deviceStatus.shutterSpeed;
> > + parsedDeviceStatus.exposureTime = deviceStatus.exposureTime;
> > parsedDeviceStatus.frameLength = deviceStatus.frameLength;
> > metadata.set("device.status", parsedDeviceStatus);
> >
> > @@ -255,7 +255,7 @@ void CamHelperImx708::populateMetadata(const MdParser::RegisterMap ®isters,
> >
> > deviceStatus.lineLength = lineLengthPckToDuration(registers.at(lineLengthHiReg) * 256 +
> > registers.at(lineLengthLoReg));
> > - deviceStatus.shutterSpeed = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > + deviceStatus.exposureTime = exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg),
> > deviceStatus.lineLength);
> > deviceStatus.analogueGain = gain(registers.at(gainHiReg) * 256 + registers.at(gainLoReg));
> > deviceStatus.frameLength = registers.at(frameLengthHiReg) * 256 + registers.at(frameLengthLoReg);
> > diff --git a/src/ipa/rpi/common/ipa_base.cpp b/src/ipa/rpi/common/ipa_base.cpp
> > index 468f36a82ab2..5fce17e67bd6 100644
> > --- a/src/ipa/rpi/common/ipa_base.cpp
> > +++ b/src/ipa/rpi/common/ipa_base.cpp
> > @@ -224,7 +224,7 @@ int32_t IpaBase::configure(const IPACameraSensorInfo &sensorInfo, const ConfigPa
> >
> > /* Supply initial values for gain and exposure. */
> > AgcStatus agcStatus;
> > - agcStatus.shutterTime = defaultExposureTime;
> > + agcStatus.exposureTime = defaultExposureTime;
> > agcStatus.analogueGain = defaultAnalogueGain;
> > applyAGC(&agcStatus, ctrls);
> >
> > @@ -265,8 +265,8 @@ int32_t IpaBase::configure(const IPACameraSensorInfo &sensorInfo, const ConfigPa
> > static_cast<float>(mode_.maxAnalogueGain));
> >
> > ctrlMap[&controls::ExposureTime] =
> > - ControlInfo(static_cast<int32_t>(mode_.minShutter.get<std::micro>()),
> > - static_cast<int32_t>(mode_.maxShutter.get<std::micro>()));
> > + ControlInfo(static_cast<int32_t>(mode_.minExposureTime.get<std::micro>()),
> > + static_cast<int32_t>(mode_.maxExposureTime.get<std::micro>()));
> >
> > /* Declare colour processing related controls for non-mono sensors. */
> > if (!monoSensor_)
> > @@ -299,11 +299,11 @@ void IpaBase::start(const ControlList &controls, StartResult *result)
> >
> > /* SwitchMode may supply updated exposure/gain values to use. */
> > AgcStatus agcStatus;
> > - agcStatus.shutterTime = 0.0s;
> > + agcStatus.exposureTime = 0.0s;
> > agcStatus.analogueGain = 0.0;
> >
> > metadata.get("agc.status", agcStatus);
> > - if (agcStatus.shutterTime && agcStatus.analogueGain) {
> > + if (agcStatus.exposureTime && agcStatus.analogueGain) {
> > ControlList ctrls(sensorCtrls_);
> > applyAGC(&agcStatus, ctrls);
> > result->controls = std::move(ctrls);
> > @@ -599,7 +599,7 @@ void IpaBase::setMode(const IPACameraSensorInfo &sensorInfo)
> > mode_.sensitivity = helper_->getModeSensitivity(mode_);
> >
> > const ControlInfo &gainCtrl = sensorCtrls_.at(V4L2_CID_ANALOGUE_GAIN);
> > - const ControlInfo &shutterCtrl = sensorCtrls_.at(V4L2_CID_EXPOSURE);
> > + const ControlInfo &exposureTimeCtrl = sensorCtrls_.at(V4L2_CID_EXPOSURE);
> >
> > mode_.minAnalogueGain = helper_->gain(gainCtrl.min().get<int32_t>());
> > mode_.maxAnalogueGain = helper_->gain(gainCtrl.max().get<int32_t>());
> > @@ -610,11 +610,15 @@ void IpaBase::setMode(const IPACameraSensorInfo &sensorInfo)
> > */
> > helper_->setCameraMode(mode_);
> >
> > - /* Shutter speed is calculated based on the limits of the frame durations. */
> > - mode_.minShutter = helper_->exposure(shutterCtrl.min().get<int32_t>(), mode_.minLineLength);
> > - mode_.maxShutter = Duration::max();
> > - helper_->getBlanking(mode_.maxShutter,
> > - mode_.minFrameDuration, mode_.maxFrameDuration);
> > + /*
> > + * Exposure time is calculated based on the limits of the frame
> > + * durations.
> > + */
> > + mode_.minExposureTime = helper_->exposure(exposureTimeCtrl.min().get<int32_t>(),
> > + mode_.minLineLength);
> > + mode_.maxExposureTime = Duration::max();
> > + helper_->getBlanking(mode_.maxExposureTime, mode_.minFrameDuration,
> > + mode_.maxFrameDuration);
> > }
> >
> > void IpaBase::setCameraTimeoutValue()
> > @@ -788,7 +792,7 @@ void IpaBase::applyControls(const ControlList &controls)
> > }
> >
> > /* The control provides units of microseconds. */
> > - agc->setFixedShutter(0, ctrl.second.get<int32_t>() * 1.0us);
> > + agc->setFixedExposureTime(0, ctrl.second.get<int32_t>() * 1.0us);
> >
> > libcameraMetadata_.set(controls::ExposureTime, ctrl.second.get<int32_t>());
> > break;
> > @@ -1281,7 +1285,7 @@ void IpaBase::fillDeviceStatus(const ControlList &sensorControls, unsigned int i
> > int32_t hblank = sensorControls.get(V4L2_CID_HBLANK).get<int32_t>();
> >
> > deviceStatus.lineLength = helper_->hblankToLineLength(hblank);
> > - deviceStatus.shutterSpeed = helper_->exposure(exposureLines, deviceStatus.lineLength);
> > + deviceStatus.exposureTime = helper_->exposure(exposureLines, deviceStatus.lineLength);
> > deviceStatus.analogueGain = helper_->gain(gainCode);
> > deviceStatus.frameLength = mode_.height + vblank;
> >
> > @@ -1308,7 +1312,7 @@ void IpaBase::reportMetadata(unsigned int ipaContext)
> > DeviceStatus *deviceStatus = rpiMetadata.getLocked<DeviceStatus>("device.status");
> > if (deviceStatus) {
> > libcameraMetadata_.set(controls::ExposureTime,
> > - deviceStatus->shutterSpeed.get<std::micro>());
> > + deviceStatus->exposureTime.get<std::micro>());
> > libcameraMetadata_.set(controls::AnalogueGain, deviceStatus->analogueGain);
> > libcameraMetadata_.set(controls::FrameDuration,
> > helper_->exposure(deviceStatus->frameLength, deviceStatus->lineLength).get<std::micro>());
> > @@ -1459,15 +1463,15 @@ void IpaBase::applyFrameDurations(Duration minFrameDuration, Duration maxFrameDu
> >
> > /*
> > * Calculate the maximum exposure time possible for the AGC to use.
> > - * getBlanking() will update maxShutter with the largest exposure
> > + * getBlanking() will update maxExposureTime with the largest exposure
> > * value possible.
> > */
> > - Duration maxShutter = Duration::max();
> > - helper_->getBlanking(maxShutter, minFrameDuration_, maxFrameDuration_);
> > + Duration maxExposureTime = Duration::max();
> > + helper_->getBlanking(maxExposureTime, minFrameDuration_, maxFrameDuration_);
> >
> > RPiController::AgcAlgorithm *agc = dynamic_cast<RPiController::AgcAlgorithm *>(
> > controller_.getAlgorithm("agc"));
> > - agc->setMaxShutter(maxShutter);
> > + agc->setMaxExposureTime(maxExposureTime);
> > }
> >
> > void IpaBase::applyAGC(const struct AgcStatus *agcStatus, ControlList &ctrls)
> > @@ -1484,14 +1488,14 @@ void IpaBase::applyAGC(const struct AgcStatus *agcStatus, ControlList &ctrls)
> > gainCode = std::clamp<int32_t>(gainCode, minGainCode, maxGainCode);
> >
> > /* getBlanking might clip exposure time to the fps limits. */
> > - Duration exposure = agcStatus->shutterTime;
> > + Duration exposure = agcStatus->exposureTime;
> > auto [vblank, hblank] = helper_->getBlanking(exposure, minFrameDuration_, maxFrameDuration_);
> > int32_t exposureLines = helper_->exposureLines(exposure,
> > helper_->hblankToLineLength(hblank));
> >
> > LOG(IPARPI, Debug) << "Applying AGC Exposure: " << exposure
> > - << " (Shutter lines: " << exposureLines << ", AGC requested "
> > - << agcStatus->shutterTime << ") Gain: "
> > + << " (Exposure lines: " << exposureLines << ", AGC requested "
> > + << agcStatus->exposureTime << ") Gain: "
> > << agcStatus->analogueGain << " (Gain Code: "
> > << gainCode << ")";
> >
> > diff --git a/src/ipa/rpi/controller/agc_algorithm.h b/src/ipa/rpi/controller/agc_algorithm.h
> > index 1132de7e050e..c97828577602 100644
> > --- a/src/ipa/rpi/controller/agc_algorithm.h
> > +++ b/src/ipa/rpi/controller/agc_algorithm.h
> > @@ -23,9 +23,9 @@ public:
> > virtual std::vector<double> const &getWeights() const = 0;
> > virtual void setEv(unsigned int channel, double ev) = 0;
> > virtual void setFlickerPeriod(libcamera::utils::Duration flickerPeriod) = 0;
> > - virtual void setFixedShutter(unsigned int channel,
> > - libcamera::utils::Duration fixedShutter) = 0;
> > - virtual void setMaxShutter(libcamera::utils::Duration maxShutter) = 0;
> > + virtual void setFixedExposureTime(unsigned int channel,
> > + libcamera::utils::Duration fixedExposureTime) = 0;
> > + virtual void setMaxExposureTime(libcamera::utils::Duration maxExposureTime) = 0;
> > virtual void setFixedAnalogueGain(unsigned int channel, double fixedAnalogueGain) = 0;
> > virtual void setMeteringMode(std::string const &meteringModeName) = 0;
> > virtual void setExposureMode(std::string const &exposureModeName) = 0;
> > diff --git a/src/ipa/rpi/controller/agc_status.h b/src/ipa/rpi/controller/agc_status.h
> > index c7c87b83a196..9308b156051c 100644
> > --- a/src/ipa/rpi/controller/agc_status.h
> > +++ b/src/ipa/rpi/controller/agc_status.h
> > @@ -28,7 +28,7 @@
> > struct AgcStatus {
> > libcamera::utils::Duration totalExposureValue; /* value for all exposure and gain for this image */
> > libcamera::utils::Duration targetExposureValue; /* (unfiltered) target total exposure AGC is aiming for */
> > - libcamera::utils::Duration shutterTime;
> > + libcamera::utils::Duration exposureTime;
> > double analogueGain;
> > std::string exposureMode;
> > std::string constraintMode;
> > @@ -36,7 +36,7 @@ struct AgcStatus {
> > double ev;
> > libcamera::utils::Duration flickerPeriod;
> > int floatingRegionEnable;
> > - libcamera::utils::Duration fixedShutter;
> > + libcamera::utils::Duration fixedExposureTime;
> > double fixedAnalogueGain;
> > unsigned int channel;
> > HdrStatus hdr;
> > diff --git a/src/ipa/rpi/controller/camera_mode.h b/src/ipa/rpi/controller/camera_mode.h
> > index 4fdb5b85b299..61162b3276d6 100644
> > --- a/src/ipa/rpi/controller/camera_mode.h
> > +++ b/src/ipa/rpi/controller/camera_mode.h
> > @@ -50,9 +50,9 @@ struct CameraMode {
> > double sensitivity;
> > /* pixel clock rate */
> > uint64_t pixelRate;
> > - /* Mode specific shutter speed limits */
> > - libcamera::utils::Duration minShutter;
> > - libcamera::utils::Duration maxShutter;
> > + /* Mode specific exposure time limits */
> > + libcamera::utils::Duration minExposureTime;
> > + libcamera::utils::Duration maxExposureTime;
> > /* Mode specific analogue gain limits */
> > double minAnalogueGain;
> > double maxAnalogueGain;
> > diff --git a/src/ipa/rpi/controller/device_status.cpp b/src/ipa/rpi/controller/device_status.cpp
> > index 68100137323a..1695764d2fa1 100644
> > --- a/src/ipa/rpi/controller/device_status.cpp
> > +++ b/src/ipa/rpi/controller/device_status.cpp
> > @@ -10,7 +10,7 @@ using namespace libcamera; /* for the Duration operator<< overload */
> >
> > std::ostream &operator<<(std::ostream &out, const DeviceStatus &d)
> > {
> > - out << "Exposure: " << d.shutterSpeed
> > + out << "Exposure time: " << d.exposureTime
> > << " Frame length: " << d.frameLength
> > << " Line length: " << d.lineLength
> > << " Gain: " << d.analogueGain;
> > diff --git a/src/ipa/rpi/controller/device_status.h b/src/ipa/rpi/controller/device_status.h
> > index 518f15b5a5a6..b1792035c55e 100644
> > --- a/src/ipa/rpi/controller/device_status.h
> > +++ b/src/ipa/rpi/controller/device_status.h
> > @@ -12,21 +12,21 @@
> > #include <libcamera/base/utils.h>
> >
> > /*
> > - * Definition of "device metadata" which stores things like shutter time and
> > + * Definition of "device metadata" which stores things like exposure time and
> > * analogue gain that downstream control algorithms will want to know.
> > */
> >
> > struct DeviceStatus {
> > DeviceStatus()
> > - : shutterSpeed(std::chrono::seconds(0)), frameLength(0),
> > + : exposureTime(std::chrono::seconds(0)), frameLength(0),
> > lineLength(std::chrono::seconds(0)), analogueGain(0.0)
> > {
> > }
> >
> > friend std::ostream &operator<<(std::ostream &out, const DeviceStatus &d);
> >
> > - /* time shutter is open */
> > - libcamera::utils::Duration shutterSpeed;
> > + /* time the image is exposed */
> > + libcamera::utils::Duration exposureTime;
> > /* frame length given in number of lines */
> > uint32_t frameLength;
> > /* line length for the current frame */
> > diff --git a/src/ipa/rpi/controller/rpi/agc.cpp b/src/ipa/rpi/controller/rpi/agc.cpp
> > index fcf7aec99375..c48fdf156591 100644
> > --- a/src/ipa/rpi/controller/rpi/agc.cpp
> > +++ b/src/ipa/rpi/controller/rpi/agc.cpp
> > @@ -127,21 +127,21 @@ void Agc::setFlickerPeriod(Duration flickerPeriod)
> > data.channel.setFlickerPeriod(flickerPeriod);
> > }
> >
> > -void Agc::setMaxShutter(Duration maxShutter)
> > +void Agc::setMaxExposureTime(Duration maxExposureTime)
> > {
> > /* Frame durations will be the same across all channels too. */
> > for (auto &data : channelData_)
> > - data.channel.setMaxShutter(maxShutter);
> > + data.channel.setMaxExposureTime(maxExposureTime);
> > }
> >
> > -void Agc::setFixedShutter(unsigned int channelIndex, Duration fixedShutter)
> > +void Agc::setFixedExposureTime(unsigned int channelIndex, Duration fixedExposureTime)
> > {
> > if (checkChannel(channelIndex))
> > return;
> >
> > - LOG(RPiAgc, Debug) << "setFixedShutter " << fixedShutter
> > + LOG(RPiAgc, Debug) << "setFixedExposureTime " << fixedExposureTime
> > << " for channel " << channelIndex;
> > - channelData_[channelIndex].channel.setFixedShutter(fixedShutter);
> > + channelData_[channelIndex].channel.setFixedExposureTime(fixedExposureTime);
> > }
> >
> > void Agc::setFixedAnalogueGain(unsigned int channelIndex, double fixedAnalogueGain)
> > diff --git a/src/ipa/rpi/controller/rpi/agc.h b/src/ipa/rpi/controller/rpi/agc.h
> > index 5d056f02e2ac..3aca000bb4c2 100644
> > --- a/src/ipa/rpi/controller/rpi/agc.h
> > +++ b/src/ipa/rpi/controller/rpi/agc.h
> > @@ -32,9 +32,9 @@ public:
> > std::vector<double> const &getWeights() const override;
> > void setEv(unsigned int channel, double ev) override;
> > void setFlickerPeriod(libcamera::utils::Duration flickerPeriod) override;
> > - void setMaxShutter(libcamera::utils::Duration maxShutter) override;
> > - void setFixedShutter(unsigned int channelIndex,
> > - libcamera::utils::Duration fixedShutter) override;
> > + void setMaxExposureTime(libcamera::utils::Duration maxExposureTime) override;
> > + void setFixedExposureTime(unsigned int channelIndex,
> > + libcamera::utils::Duration fixedExposureTime) override;
> > void setFixedAnalogueGain(unsigned int channelIndex,
> > double fixedAnalogueGain) override;
> > void setMeteringMode(std::string const &meteringModeName) override;
> > diff --git a/src/ipa/rpi/controller/rpi/agc_channel.cpp b/src/ipa/rpi/controller/rpi/agc_channel.cpp
> > index 8583f4f31907..143359437f3a 100644
> > --- a/src/ipa/rpi/controller/rpi/agc_channel.cpp
> > +++ b/src/ipa/rpi/controller/rpi/agc_channel.cpp
> > @@ -67,7 +67,7 @@ int AgcExposureMode::read(const libcamera::YamlObject ¶ms)
> > auto value = params["shutter"].getList<double>();
> > if (!value)
> > return -EINVAL;
> > - std::transform(value->begin(), value->end(), std::back_inserter(shutter),
> > + std::transform(value->begin(), value->end(), std::back_inserter(exposureTime),
> > [](double v) { return v * 1us; });
> >
> > value = params["gain"].getList<double>();
> > @@ -75,13 +75,13 @@ int AgcExposureMode::read(const libcamera::YamlObject ¶ms)
> > return -EINVAL;
> > gain = std::move(*value);
> >
> > - if (shutter.size() < 2 || gain.size() < 2) {
> > + if (exposureTime.size() < 2 || gain.size() < 2) {
> > LOG(RPiAgc, Error)
> > << "AgcExposureMode: must have at least two entries in exposure profile";
> > return -EINVAL;
> > }
> >
> > - if (shutter.size() != gain.size()) {
> > + if (exposureTime.size() != gain.size()) {
> > LOG(RPiAgc, Error)
> > << "AgcExposureMode: expect same number of exposure and gain entries in exposure profile";
> > return -EINVAL;
> > @@ -262,7 +262,7 @@ int AgcConfig::read(const libcamera::YamlObject ¶ms)
> > }
> >
> > AgcChannel::ExposureValues::ExposureValues()
> > - : shutter(0s), analogueGain(0),
> > + : exposureTime(0s), analogueGain(0),
> > totalExposure(0s), totalExposureNoDG(0s)
> > {
> > }
> > @@ -271,7 +271,7 @@ AgcChannel::AgcChannel()
> > : meteringMode_(nullptr), exposureMode_(nullptr), constraintMode_(nullptr),
> > frameCount_(0), lockCount_(0),
> > lastTargetExposure_(0s), ev_(1.0), flickerPeriod_(0s),
> > - maxShutter_(0s), fixedShutter_(0s), fixedAnalogueGain_(0.0)
> > + maxExposureTime_(0s), fixedExposureTime_(0s), fixedAnalogueGain_(0.0)
> > {
> > /* Set AWB default values in case early frames have no updates in metadata. */
> > awb_.gainR = 1.0;
> > @@ -312,31 +312,31 @@ int AgcChannel::read(const libcamera::YamlObject ¶ms,
> > exposureMode_ = &config_.exposureModes[exposureModeName_];
> > constraintModeName_ = config_.defaultConstraintMode;
> > constraintMode_ = &config_.constraintModes[constraintModeName_];
> > - /* Set up the "last shutter/gain" values, in case AGC starts "disabled". */
> > - status_.shutterTime = config_.defaultExposureTime;
> > + /* Set up the "last exposure time/gain" values, in case AGC starts "disabled". */
> > + status_.exposureTime = config_.defaultExposureTime;
> > status_.analogueGain = config_.defaultAnalogueGain;
> > return 0;
> > }
> >
> > void AgcChannel::disableAuto()
> > {
> > - fixedShutter_ = status_.shutterTime;
> > + fixedExposureTime_ = status_.exposureTime;
> > fixedAnalogueGain_ = status_.analogueGain;
> > }
> >
> > void AgcChannel::enableAuto()
> > {
> > - fixedShutter_ = 0s;
> > + fixedExposureTime_ = 0s;
> > fixedAnalogueGain_ = 0;
> > }
> >
> > unsigned int AgcChannel::getConvergenceFrames() const
> > {
> > /*
> > - * If shutter and gain have been explicitly set, there is no
> > + * If exposure time and gain have been explicitly set, there is no
> > * convergence to happen, so no need to drop any frames - return zero.
> > */
> > - if (fixedShutter_ && fixedAnalogueGain_)
> > + if (fixedExposureTime_ && fixedAnalogueGain_)
> > return 0;
> > else
> > return config_.convergenceFrames;
> > @@ -364,16 +364,16 @@ void AgcChannel::setFlickerPeriod(Duration flickerPeriod)
> > flickerPeriod_ = flickerPeriod;
> > }
> >
> > -void AgcChannel::setMaxShutter(Duration maxShutter)
> > +void AgcChannel::setMaxExposureTime(Duration maxExposureTime)
> > {
> > - maxShutter_ = maxShutter;
> > + maxExposureTime_ = maxExposureTime;
> > }
> >
> > -void AgcChannel::setFixedShutter(Duration fixedShutter)
> > +void AgcChannel::setFixedExposureTime(Duration fixedExposureTime)
> > {
> > - fixedShutter_ = fixedShutter;
> > + fixedExposureTime_ = fixedExposureTime;
> > /* Set this in case someone calls disableAuto() straight after. */
> > - status_.shutterTime = limitShutter(fixedShutter_);
> > + status_.exposureTime = limitExposureTime(fixedExposureTime_);
> > }
> >
> > void AgcChannel::setFixedAnalogueGain(double fixedAnalogueGain)
> > @@ -413,22 +413,22 @@ void AgcChannel::switchMode(CameraMode const &cameraMode,
> > double lastSensitivity = mode_.sensitivity;
> > mode_ = cameraMode;
> >
> > - Duration fixedShutter = limitShutter(fixedShutter_);
> > - if (fixedShutter && fixedAnalogueGain_) {
> > + Duration fixedExposureTime = limitExposureTime(fixedExposureTime_);
> > + if (fixedExposureTime && fixedAnalogueGain_) {
> > /* We're going to reset the algorithm here with these fixed values. */
> > fetchAwbStatus(metadata);
> > double minColourGain = std::min({ awb_.gainR, awb_.gainG, awb_.gainB, 1.0 });
> > ASSERT(minColourGain != 0.0);
> >
> > /* This is the equivalent of computeTargetExposure and applyDigitalGain. */
> > - target_.totalExposureNoDG = fixedShutter_ * fixedAnalogueGain_;
> > + target_.totalExposureNoDG = fixedExposureTime_ * fixedAnalogueGain_;
> > target_.totalExposure = target_.totalExposureNoDG / minColourGain;
> >
> > /* Equivalent of filterExposure. This resets any "history". */
> > filtered_ = target_;
> >
> > /* Equivalent of divideUpExposure. */
> > - filtered_.shutter = fixedShutter;
> > + filtered_.exposureTime = fixedExposureTime;
> > filtered_.analogueGain = fixedAnalogueGain_;
> > } else if (status_.totalExposureValue) {
> > /*
> > @@ -450,14 +450,15 @@ void AgcChannel::switchMode(CameraMode const &cameraMode,
> > divideUpExposure();
> > } else {
> > /*
> > - * We come through here on startup, when at least one of the shutter
> > - * or gain has not been fixed. We must still write those values out so
> > - * that they will be applied immediately. We supply some arbitrary defaults
> > - * for any that weren't set.
> > + * We come through here on startup, when at least one of the
> > + * exposure time or gain has not been fixed. We must still
> > + * write those values out so that they will be applied
> > + * immediately. We supply some arbitrary defaults for any that
> > + * weren't set.
> > */
> >
> > /* Equivalent of divideUpExposure. */
> > - filtered_.shutter = fixedShutter ? fixedShutter : config_.defaultExposureTime;
> > + filtered_.exposureTime = fixedExposureTime ? fixedExposureTime : config_.defaultExposureTime;
> > filtered_.analogueGain = fixedAnalogueGain_ ? fixedAnalogueGain_ : config_.defaultAnalogueGain;
> > }
> >
> > @@ -483,7 +484,7 @@ void AgcChannel::prepare(Metadata *imageMetadata)
> > /* Process has run, so we have meaningful values. */
> > DeviceStatus deviceStatus;
> > if (imageMetadata->get("device.status", deviceStatus) == 0) {
> > - Duration actualExposure = deviceStatus.shutterSpeed *
> > + Duration actualExposure = deviceStatus.exposureTime *
> > deviceStatus.analogueGain;
> > if (actualExposure) {
> > double digitalGain = totalExposureValue / actualExposure;
> > @@ -537,7 +538,7 @@ void AgcChannel::process(StatisticsPtr &stats, DeviceStatus const &deviceStatus,
> > */
> > bool desaturate = applyDigitalGain(gain, targetY, channelBound);
> > /*
> > - * The last thing is to divide up the exposure value into a shutter time
> > + * The last thing is to divide up the exposure value into a exposure time
> > * and analogue gain, according to the current exposure mode.
> > */
> > divideUpExposure();
> > @@ -553,7 +554,7 @@ bool AgcChannel::updateLockStatus(DeviceStatus const &deviceStatus)
> > const double resetMargin = 1.5;
> >
> > /* Add 200us to the exposure time error to allow for line quantisation. */
> > - Duration exposureError = lastDeviceStatus_.shutterSpeed * errorFactor + 200us;
> > + Duration exposureError = lastDeviceStatus_.exposureTime * errorFactor + 200us;
> > double gainError = lastDeviceStatus_.analogueGain * errorFactor;
> > Duration targetError = lastTargetExposure_ * errorFactor;
> >
> > @@ -562,15 +563,15 @@ bool AgcChannel::updateLockStatus(DeviceStatus const &deviceStatus)
> > * the values we keep requesting may be unachievable. For this reason
> > * we only insist that we're close to values in the past few frames.
> > */
> > - if (deviceStatus.shutterSpeed > lastDeviceStatus_.shutterSpeed - exposureError &&
> > - deviceStatus.shutterSpeed < lastDeviceStatus_.shutterSpeed + exposureError &&
> > + if (deviceStatus.exposureTime > lastDeviceStatus_.exposureTime - exposureError &&
> > + deviceStatus.exposureTime < lastDeviceStatus_.exposureTime + exposureError &&
> > deviceStatus.analogueGain > lastDeviceStatus_.analogueGain - gainError &&
> > deviceStatus.analogueGain < lastDeviceStatus_.analogueGain + gainError &&
> > status_.targetExposureValue > lastTargetExposure_ - targetError &&
> > status_.targetExposureValue < lastTargetExposure_ + targetError)
> > lockCount_ = std::min(lockCount_ + 1, maxLockCount);
> > - else if (deviceStatus.shutterSpeed < lastDeviceStatus_.shutterSpeed - resetMargin * exposureError ||
> > - deviceStatus.shutterSpeed > lastDeviceStatus_.shutterSpeed + resetMargin * exposureError ||
> > + else if (deviceStatus.exposureTime < lastDeviceStatus_.exposureTime - resetMargin * exposureError ||
> > + deviceStatus.exposureTime > lastDeviceStatus_.exposureTime + resetMargin * exposureError ||
> > deviceStatus.analogueGain < lastDeviceStatus_.analogueGain - resetMargin * gainError ||
> > deviceStatus.analogueGain > lastDeviceStatus_.analogueGain + resetMargin * gainError ||
> > status_.targetExposureValue < lastTargetExposure_ - resetMargin * targetError ||
> > @@ -588,11 +589,11 @@ void AgcChannel::housekeepConfig()
> > {
> > /* First fetch all the up-to-date settings, so no one else has to do it. */
> > status_.ev = ev_;
> > - status_.fixedShutter = limitShutter(fixedShutter_);
> > + status_.fixedExposureTime = limitExposureTime(fixedExposureTime_);
> > status_.fixedAnalogueGain = fixedAnalogueGain_;
> > status_.flickerPeriod = flickerPeriod_;
> > - LOG(RPiAgc, Debug) << "ev " << status_.ev << " fixedShutter "
> > - << status_.fixedShutter << " fixedAnalogueGain "
> > + LOG(RPiAgc, Debug) << "ev " << status_.ev << " fixedExposureTime "
> > + << status_.fixedExposureTime << " fixedAnalogueGain "
> > << status_.fixedAnalogueGain;
> > /*
> > * Make sure the "mode" pointers point to the up-to-date things, if
> > @@ -636,10 +637,10 @@ void AgcChannel::housekeepConfig()
> >
> > void AgcChannel::fetchCurrentExposure(DeviceStatus const &deviceStatus)
> > {
> > - current_.shutter = deviceStatus.shutterSpeed;
> > + current_.exposureTime = deviceStatus.exposureTime;
> > current_.analogueGain = deviceStatus.analogueGain;
> > current_.totalExposure = 0s; /* this value is unused */
> > - current_.totalExposureNoDG = current_.shutter * current_.analogueGain;
> > + current_.totalExposureNoDG = current_.exposureTime * current_.analogueGain;
> > }
> >
> > void AgcChannel::fetchAwbStatus(Metadata *imageMetadata)
> > @@ -777,17 +778,17 @@ void AgcChannel::computeGain(StatisticsPtr &statistics, Metadata *imageMetadata,
> >
> > void AgcChannel::computeTargetExposure(double gain)
> > {
> > - if (status_.fixedShutter && status_.fixedAnalogueGain) {
> > + if (status_.fixedExposureTime && status_.fixedAnalogueGain) {
> > /*
> > - * When ag and shutter are both fixed, we need to drive the
> > - * total exposure so that we end up with a digital gain of at least
> > - * 1/minColourGain. Otherwise we'd desaturate channels causing
> > - * white to go cyan or magenta.
> > + * When analogue gain and exposure time are both fixed, we need
> > + * to drive the total exposure so that we end up with a digital
> > + * gain of at least 1/minColourGain. Otherwise we'd desaturate
> > + * channels causing white to go cyan or magenta.
> > */
> > double minColourGain = std::min({ awb_.gainR, awb_.gainG, awb_.gainB, 1.0 });
> > ASSERT(minColourGain != 0.0);
> > target_.totalExposure =
> > - status_.fixedShutter * status_.fixedAnalogueGain / minColourGain;
> > + status_.fixedExposureTime * status_.fixedAnalogueGain / minColourGain;
> > } else {
> > /*
> > * The statistics reflect the image without digital gain, so the final
> > @@ -795,12 +796,12 @@ void AgcChannel::computeTargetExposure(double gain)
> > */
> > target_.totalExposure = current_.totalExposureNoDG * gain;
> > /* The final target exposure is also limited to what the exposure mode allows. */
> > - Duration maxShutter = status_.fixedShutter
> > - ? status_.fixedShutter
> > - : exposureMode_->shutter.back();
> > - maxShutter = limitShutter(maxShutter);
> > + Duration maxExposureTime = status_.fixedExposureTime
> > + ? status_.fixedExposureTime
> > + : exposureMode_->exposureTime.back();
> > + maxExposureTime = limitExposureTime(maxExposureTime);
> > Duration maxTotalExposure =
> > - maxShutter *
> > + maxExposureTime *
> > (status_.fixedAnalogueGain != 0.0
> > ? status_.fixedAnalogueGain
> > : exposureMode_->gain.back());
> > @@ -884,11 +885,12 @@ void AgcChannel::filterExposure()
> > double stableRegion = config_.stableRegion;
> >
> > /*
> > - * AGC adapts instantly if both shutter and gain are directly specified
> > - * or we're in the startup phase. Also disable the stable region, because we want
> > - * to reflect any user exposure/gain updates, however small.
> > + * AGC adapts instantly if both exposure time and gain are directly
> > + * specified or we're in the startup phase. Also disable the stable
> > + * region, because we want to reflect any user exposure/gain updates,
> > + * however small.
> > */
> > - if ((status_.fixedShutter && status_.fixedAnalogueGain) ||
> > + if ((status_.fixedExposureTime && status_.fixedAnalogueGain) ||
> > frameCount_ <= config_.startupFrames) {
> > speed = 1.0;
> > stableRegion = 0.0;
> > @@ -916,34 +918,34 @@ void AgcChannel::filterExposure()
> > void AgcChannel::divideUpExposure()
> > {
> > /*
> > - * Sending the fixed shutter/gain cases through the same code may seem
> > - * unnecessary, but it will make more sense when extend this to cover
> > - * variable aperture.
> > + * Sending the fixed exposure time/gain cases through the same code may
> > + * seem unnecessary, but it will make more sense when extend this to
> > + * cover variable aperture.
> > */
> > Duration exposureValue = filtered_.totalExposureNoDG;
> > - Duration shutterTime;
> > + Duration exposureTime;
> > double analogueGain;
> > - shutterTime = status_.fixedShutter ? status_.fixedShutter
> > - : exposureMode_->shutter[0];
> > - shutterTime = limitShutter(shutterTime);
> > + exposureTime = status_.fixedExposureTime ? status_.fixedExposureTime
> > + : exposureMode_->exposureTime[0];
> > + exposureTime = limitExposureTime(exposureTime);
> > analogueGain = status_.fixedAnalogueGain != 0.0 ? status_.fixedAnalogueGain
> > : exposureMode_->gain[0];
> > analogueGain = limitGain(analogueGain);
> > - if (shutterTime * analogueGain < exposureValue) {
> > + if (exposureTime * analogueGain < exposureValue) {
> > for (unsigned int stage = 1;
> > stage < exposureMode_->gain.size(); stage++) {
> > - if (!status_.fixedShutter) {
> > - Duration stageShutter =
> > - limitShutter(exposureMode_->shutter[stage]);
> > - if (stageShutter * analogueGain >= exposureValue) {
> > - shutterTime = exposureValue / analogueGain;
> > + if (!status_.fixedExposureTime) {
> > + Duration stageExposureTime =
> > + limitExposureTime(exposureMode_->exposureTime[stage]);
> > + if (stageExposureTime * analogueGain >= exposureValue) {
> > + exposureTime = exposureValue / analogueGain;
> > break;
> > }
> > - shutterTime = stageShutter;
> > + exposureTime = stageExposureTime;
> > }
> > if (status_.fixedAnalogueGain == 0.0) {
> > - if (exposureMode_->gain[stage] * shutterTime >= exposureValue) {
> > - analogueGain = exposureValue / shutterTime;
> > + if (exposureMode_->gain[stage] * exposureTime >= exposureValue) {
> > + analogueGain = exposureValue / exposureTime;
> > break;
> > }
> > analogueGain = exposureMode_->gain[stage];
> > @@ -951,18 +953,19 @@ void AgcChannel::divideUpExposure()
> > }
> > }
> > }
> > - LOG(RPiAgc, Debug) << "Divided up shutter and gain are " << shutterTime << " and "
> > - << analogueGain;
> > + LOG(RPiAgc, Debug)
> > + << "Divided up exposure time and gain are " << exposureTime
> > + << " and " << analogueGain;
> > /*
> > - * Finally adjust shutter time for flicker avoidance (require both
> > - * shutter and gain not to be fixed).
> > + * Finally adjust exposure time for flicker avoidance (require both
> > + * exposure time and gain not to be fixed).
> > */
> > - if (!status_.fixedShutter && !status_.fixedAnalogueGain &&
> > + if (!status_.fixedExposureTime && !status_.fixedAnalogueGain &&
> > status_.flickerPeriod) {
> > - int flickerPeriods = shutterTime / status_.flickerPeriod;
> > + int flickerPeriods = exposureTime / status_.flickerPeriod;
> > if (flickerPeriods) {
> > - Duration newShutterTime = flickerPeriods * status_.flickerPeriod;
> > - analogueGain *= shutterTime / newShutterTime;
> > + Duration newExposureTime = flickerPeriods * status_.flickerPeriod;
> > + analogueGain *= exposureTime / newExposureTime;
> > /*
> > * We should still not allow the ag to go over the
> > * largest value in the exposure mode. Note that this
> > @@ -971,12 +974,12 @@ void AgcChannel::divideUpExposure()
> > */
> > analogueGain = std::min(analogueGain, exposureMode_->gain.back());
> > analogueGain = limitGain(analogueGain);
> > - shutterTime = newShutterTime;
> > + exposureTime = newExposureTime;
> > }
> > - LOG(RPiAgc, Debug) << "After flicker avoidance, shutter "
> > - << shutterTime << " gain " << analogueGain;
> > + LOG(RPiAgc, Debug) << "After flicker avoidance, exposure time "
> > + << exposureTime << " gain " << analogueGain;
> > }
> > - filtered_.shutter = shutterTime;
> > + filtered_.exposureTime = exposureTime;
> > filtered_.analogueGain = analogueGain;
> > }
> >
> > @@ -984,7 +987,7 @@ void AgcChannel::writeAndFinish(Metadata *imageMetadata, bool desaturate)
> > {
> > status_.totalExposureValue = filtered_.totalExposure;
> > status_.targetExposureValue = desaturate ? 0s : target_.totalExposure;
> > - status_.shutterTime = filtered_.shutter;
> > + status_.exposureTime = filtered_.exposureTime;
> > status_.analogueGain = filtered_.analogueGain;
> > /*
> > * Write to metadata as well, in case anyone wants to update the camera
> > @@ -993,32 +996,32 @@ void AgcChannel::writeAndFinish(Metadata *imageMetadata, bool desaturate)
> > imageMetadata->set("agc.status", status_);
> > LOG(RPiAgc, Debug) << "Output written, total exposure requested is "
> > << filtered_.totalExposure;
> > - LOG(RPiAgc, Debug) << "Camera exposure update: shutter time " << filtered_.shutter
> > + LOG(RPiAgc, Debug) << "Camera exposure update: exposure time " << filtered_.exposureTime
> > << " analogue gain " << filtered_.analogueGain;
> > }
> >
> > -Duration AgcChannel::limitShutter(Duration shutter)
> > +Duration AgcChannel::limitExposureTime(Duration exposureTime)
> > {
> > /*
> > - * shutter == 0 is a special case for fixed shutter values, and must pass
> > - * through unchanged
> > + * exposureTime == 0 is a special case for fixed exposure time values,
> > + * and must pass through unchanged.
> > */
> > - if (!shutter)
> > - return shutter;
> > + if (!exposureTime)
> > + return exposureTime;
> >
> > - shutter = std::clamp(shutter, mode_.minShutter, maxShutter_);
> > - return shutter;
> > + exposureTime = std::clamp(exposureTime, mode_.minExposureTime, maxExposureTime_);
> > + return exposureTime;
> > }
> >
> > double AgcChannel::limitGain(double gain) const
> > {
> > /*
> > - * Only limit the lower bounds of the gain value to what the sensor limits.
> > - * The upper bound on analogue gain will be made up with additional digital
> > - * gain applied by the ISP.
> > + * Only limit the lower bounds of the gain value to what the sensor
> > + * limits. The upper bound on analogue gain will be made up with
> > + * additional digital gain applied by the ISP.
> > *
> > - * gain == 0.0 is a special case for fixed shutter values, and must pass
> > - * through unchanged
> > + * gain == 0.0 is a special case for fixed exposure time values, and
> > + * must pass through unchanged.
> > */
> > if (!gain)
> > return gain;
> > diff --git a/src/ipa/rpi/controller/rpi/agc_channel.h b/src/ipa/rpi/controller/rpi/agc_channel.h
> > index 58368889e6a2..734e5efd3266 100644
> > --- a/src/ipa/rpi/controller/rpi/agc_channel.h
> > +++ b/src/ipa/rpi/controller/rpi/agc_channel.h
> > @@ -30,7 +30,7 @@ struct AgcMeteringMode {
> > };
> >
> > struct AgcExposureMode {
> > - std::vector<libcamera::utils::Duration> shutter;
> > + std::vector<libcamera::utils::Duration> exposureTime;
> > std::vector<double> gain;
> > int read(const libcamera::YamlObject ¶ms);
> > };
> > @@ -90,8 +90,8 @@ public:
> > std::vector<double> const &getWeights() const;
> > void setEv(double ev);
> > void setFlickerPeriod(libcamera::utils::Duration flickerPeriod);
> > - void setMaxShutter(libcamera::utils::Duration maxShutter);
> > - void setFixedShutter(libcamera::utils::Duration fixedShutter);
> > + void setMaxExposureTime(libcamera::utils::Duration maxExposureTime);
> > + void setFixedExposureTime(libcamera::utils::Duration fixedExposureTime);
> > void setFixedAnalogueGain(double fixedAnalogueGain);
> > void setMeteringMode(std::string const &meteringModeName);
> > void setExposureMode(std::string const &exposureModeName);
> > @@ -117,7 +117,7 @@ private:
> > bool applyDigitalGain(double gain, double targetY, bool channelBound);
> > void divideUpExposure();
> > void writeAndFinish(Metadata *imageMetadata, bool desaturate);
> > - libcamera::utils::Duration limitShutter(libcamera::utils::Duration shutter);
> > + libcamera::utils::Duration limitExposureTime(libcamera::utils::Duration exposureTime);
> > double limitGain(double gain) const;
> > AgcMeteringMode *meteringMode_;
> > AgcExposureMode *exposureMode_;
> > @@ -128,7 +128,7 @@ private:
> > struct ExposureValues {
> > ExposureValues();
> >
> > - libcamera::utils::Duration shutter;
> > + libcamera::utils::Duration exposureTime;
> > double analogueGain;
> > libcamera::utils::Duration totalExposure;
> > libcamera::utils::Duration totalExposureNoDG; /* without digital gain */
> > @@ -146,8 +146,8 @@ private:
> > std::string constraintModeName_;
> > double ev_;
> > libcamera::utils::Duration flickerPeriod_;
> > - libcamera::utils::Duration maxShutter_;
> > - libcamera::utils::Duration fixedShutter_;
> > + libcamera::utils::Duration maxExposureTime_;
> > + libcamera::utils::Duration fixedExposureTime_;
> > double fixedAnalogueGain_;
> > };
> >
> > diff --git a/src/ipa/rpi/controller/rpi/lux.cpp b/src/ipa/rpi/controller/rpi/lux.cpp
> > index 652d85d7e22f..27b89a8f6658 100644
> > --- a/src/ipa/rpi/controller/rpi/lux.cpp
> > +++ b/src/ipa/rpi/controller/rpi/lux.cpp
> > @@ -40,7 +40,7 @@ int Lux::read(const libcamera::YamlObject ¶ms)
> > auto value = params["reference_shutter_speed"].get<double>();
> > if (!value)
> > return -EINVAL;
> > - referenceShutterSpeed_ = *value * 1.0us;
> > + referenceExposureTime_ = *value * 1.0us;
> >
> > value = params["reference_gain"].get<double>();
> > if (!value)
> > @@ -82,11 +82,11 @@ void Lux::process(StatisticsPtr &stats, Metadata *imageMetadata)
> > double currentAperture = deviceStatus.aperture.value_or(currentAperture_);
> > double currentY = stats->yHist.interQuantileMean(0, 1);
> > double gainRatio = referenceGain_ / currentGain;
> > - double shutterSpeedRatio =
> > - referenceShutterSpeed_ / deviceStatus.shutterSpeed;
> > + double exposureTimeRatio =
> > + referenceExposureTime_ / deviceStatus.exposureTime;
> > double apertureRatio = referenceAperture_ / currentAperture;
> > double yRatio = currentY * (65536 / stats->yHist.bins()) / referenceY_;
> > - double estimatedLux = shutterSpeedRatio * gainRatio *
> > + double estimatedLux = exposureTimeRatio * gainRatio *
> > apertureRatio * apertureRatio *
> > yRatio * referenceLux_;
> > LuxStatus status;
> > diff --git a/src/ipa/rpi/controller/rpi/lux.h b/src/ipa/rpi/controller/rpi/lux.h
> > index 89f441fc4f6e..da007fe9ac7d 100644
> > --- a/src/ipa/rpi/controller/rpi/lux.h
> > +++ b/src/ipa/rpi/controller/rpi/lux.h
> > @@ -32,7 +32,7 @@ private:
> > * These values define the conditions of the reference image, against
> > * which we compare the new image.
> > */
> > - libcamera::utils::Duration referenceShutterSpeed_;
> > + libcamera::utils::Duration referenceExposureTime_;
> > double referenceGain_;
> > double referenceAperture_; /* units of 1/f */
> > double referenceY_; /* out of 65536 */
> > diff --git a/src/libcamera/control_ids_core.yaml b/src/libcamera/control_ids_core.yaml
> > index d34a2d068b60..d45cf8e56187 100644
> > --- a/src/libcamera/control_ids_core.yaml
> > +++ b/src/libcamera/control_ids_core.yaml
> > @@ -102,7 +102,7 @@ controls:
> > Specify an exposure mode for the AE algorithm to use.
> >
> > The exposure modes specify how the desired total exposure is divided
> > - between the shutter time and the sensor's analogue gain. They are
> > + between the exposure time and the sensor's analogue gain. They are
> > platform specific, and not all exposure modes may be supported.
> > enum:
> > - name: ExposureNormal
> > @@ -135,8 +135,7 @@ controls:
> > - ExposureTime:
> > type: int32_t
> > description: |
> > - Exposure time (shutter speed) for the frame applied in the sensor
> > - device.
> > + Exposure time for the frame applied in the sensor device.
> >
> > This value is specified in micro-seconds.
> >
> > @@ -463,14 +462,13 @@ controls:
> > values to be the same. Setting both values to 0 reverts to using the
> > camera defaults.
> >
> > - The maximum frame duration provides the absolute limit to the shutter
> > - speed computed by the AE algorithm and it overrides any exposure mode
> > + The maximum frame duration provides the absolute limit to the exposure
> > + time computed by the AE algorithm and it overrides any exposure mode
> > setting specified with controls::AeExposureMode. Similarly, when a
> > manual exposure time is set through controls::ExposureTime, it also
> > gets clipped to the limits set by this control. When reported in
> > - metadata, the control expresses the minimum and maximum frame
> > - durations used after being clipped to the sensor provided frame
> > - duration limits.
> > + metadata, the control expresses the minimum and maximum frame durations
> > + used after being clipped to the sensor provided frame duration limits.
> >
> > \sa AeExposureMode
> > \sa ExposureTime
> > diff --git a/utils/tuning/libtuning/modules/agc/rkisp1.py b/utils/tuning/libtuning/modules/agc/rkisp1.py
> > index 7147028a774a..1a4dbe7b416a 100644
> > --- a/utils/tuning/libtuning/modules/agc/rkisp1.py
> > +++ b/utils/tuning/libtuning/modules/agc/rkisp1.py
> > @@ -47,9 +47,9 @@ class AGCRkISP1(AGC):
> > }
> >
> > def _generate_exposure_modes(self) -> dict:
> > - normal = {'shutter': [100, 10000, 30000, 60000, 120000],
> > + normal = {'exposure-time': [100, 10000, 30000, 60000, 120000],
> > 'gain': [2.0, 4.0, 6.0, 6.0, 6.0]}
> > - short = {'shutter': [100, 5000, 10000, 20000, 120000],
> > + short = {'exposure-time': [100, 5000, 10000, 20000, 120000],
> > 'gain': [2.0, 4.0, 6.0, 6.0, 6.0]}
> >
> > return {'ExposureNormal': normal, 'ExposureShort': short}
> >
> > base-commit: d5217b16020c659145f9d6dbf5849129b8500967
--
Regards,
Laurent Pinchart
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