[libcamera-devel] [PATCH 2/3] pipeline: ipa: raspberrypi: Correctly report available control limits

Naushir Patuck naush at raspberrypi.com
Tue Jun 21 14:36:09 CEST 2022


Hi Kieran,

Thank you for your feedback.

On Tue, 21 Jun 2022 at 13:15, Kieran Bingham <
kieran.bingham at ideasonboard.com> wrote:

> Quoting Naushir Patuck via libcamera-devel (2022-06-10 13:25:32)
> > The ipa currently advertises a static ControlInfoMap to specify the
> available
> > controls and their limits. Fix this limitation by having the IPA
> populate a new
> > ControlInfoMap with updated limits for ExposureTime, AnalogueGain, and
> > FrameDurationLimits controls based on the current sensor mode. This new
> > ControlInfoMap is then returned back to the pipeline handler and
> available to
> > the application after a successful Camera::Configure() call.
> >
> > Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
> > ---
> >  include/libcamera/ipa/raspberrypi.mojom       |  1 +
> >  src/ipa/raspberrypi/raspberrypi.cpp           | 24 ++++++++++++++++---
> >  .../pipeline/raspberrypi/raspberrypi.cpp      |  3 +++
> >  3 files changed, 25 insertions(+), 3 deletions(-)
> >
> > diff --git a/include/libcamera/ipa/raspberrypi.mojom
> b/include/libcamera/ipa/raspberrypi.mojom
> > index 77f52c282b0f..c0de435b7b33 100644
> > --- a/include/libcamera/ipa/raspberrypi.mojom
> > +++ b/include/libcamera/ipa/raspberrypi.mojom
> > @@ -45,6 +45,7 @@ struct IPAConfig {
> >
> >  struct IPAConfigResult {
>
> Aha, I see the precedent for "Result" now. so perhaps it's more suitable
> in the previous patch than I realised.
>
>
> >         float modeSensitivity;
> > +       libcamera.ControlInfoMap controlInfo;
> >  };
> >
> >  struct StartConfig {
> > diff --git a/src/ipa/raspberrypi/raspberrypi.cpp
> b/src/ipa/raspberrypi/raspberrypi.cpp
> > index 089528f5e126..295f6b735dc0 100644
> > --- a/src/ipa/raspberrypi/raspberrypi.cpp
> > +++ b/src/ipa/raspberrypi/raspberrypi.cpp
> > @@ -74,8 +74,6 @@ constexpr Duration controllerMinFrameDuration = 1.0s /
> 30.0;
> >  /* List of controls handled by the Raspberry Pi IPA */
> >  static const ControlInfoMap::Map ipaControls{
> >         { &controls::AeEnable, ControlInfo(false, true) },
> > -       { &controls::ExposureTime, ControlInfo(0, 999999) },
> > -       { &controls::AnalogueGain, ControlInfo(1.0f, 32.0f) },
> >         { &controls::AeMeteringMode,
> ControlInfo(controls::AeMeteringModeValues) },
> >         { &controls::AeConstraintMode,
> ControlInfo(controls::AeConstraintModeValues) },
> >         { &controls::AeExposureMode,
> ControlInfo(controls::AeExposureModeValues) },
> > @@ -89,7 +87,6 @@ static const ControlInfoMap::Map ipaControls{
> >         { &controls::Sharpness, ControlInfo(0.0f, 16.0f, 1.0f) },
> >         { &controls::ColourCorrectionMatrix, ControlInfo(-16.0f, 16.0f)
> },
> >         { &controls::ScalerCrop, ControlInfo(Rectangle{},
> Rectangle(65535, 65535, 65535, 65535), Rectangle{}) },
> > -       { &controls::FrameDurationLimits, ControlInfo(INT64_C(1000),
> INT64_C(1000000000)) },
> >         { &controls::draft::NoiseReductionMode,
> ControlInfo(controls::draft::NoiseReductionModeValues) }
> >  };
> >
> > @@ -446,6 +443,27 @@ int IPARPi::configure(const IPACameraSensorInfo
> &sensorInfo,
> >         ASSERT(controls);
> >         *controls = std::move(ctrls);
> >
> > +       /*
> > +        * Apply the correct limits to the exposure, gain and frame
> duration controls
> > +        * based on the current sensor mode.
> > +        */
> > +       ControlInfoMap::Map ctrlMap = ipaControls;
> > +       const Duration minSensorFrameDuration = mode_.min_frame_length *
> mode_.line_length;
> > +       const Duration maxSensorFrameDuration = mode_.max_frame_length *
> mode_.line_length;
> > +       ctrlMap.emplace(&controls::FrameDurationLimits,
> > +
>  ControlInfo(static_cast<int64_t>(minSensorFrameDuration.get<std::micro>()),
> > +
>  static_cast<int64_t>(maxSensorFrameDuration.get<std::micro>())));
> > +
> > +       ctrlMap.emplace(&controls::AnalogueGain,
> > +                       ControlInfo(1.0f,
> static_cast<float>(helper_->Gain(maxSensorGainCode_))));
> > +
> > +       const uint32_t exposureMin =
> sensorCtrls_.at(V4L2_CID_EXPOSURE).min().get<int32_t>();
> > +       const uint32_t exposureMax =
> sensorCtrls_.at(V4L2_CID_EXPOSURE).max().get<int32_t>();
> > +       ctrlMap.emplace(&controls::ExposureTime,
> > +
>  ControlInfo(static_cast<int32_t>(helper_->Exposure(exposureMin).get<std::micro>()),
> > +
>  static_cast<int32_t>(helper_->Exposure(exposureMax).get<std::micro>())));
> > +
> > +       result->controlInfo = ControlInfoMap(std::move(ctrlMap),
> controls::controls);
>
>
> aha, this means applications can't read the exposure time / gain
> controls before the camera is configured.
>
> I think that sounds 'correct' - but I wonder if we need to make that
> clear in some documentation somewhere, or somehow in an extension of
> 'simple-cam' showing how to manage camera controls. (Not to block this
> patch of course).
>

I did stop to think what to do here.  We could add ControlInfo for
ExposureTime and AnalogueGain for the "default" sensor mode, but
getting to the sensor mode is a bit more difficult in ipa::init() as things
stand.  Additionally, these values would likely have to be ignored by
the application.  It has to do a camera::Configure() call before starting,
so the values might have changed, rendering the previous values as
invalid.


>
>
> We should make sure applications realise they have to recheck controls
> after a configuration operation. (Maybe that's obvious .. I'm not sure).
>

Documenting this is probably a good thing so as to avoid application writers
from tripping up!

Regards,
Naush


>
> I was dwelling on if we should only send the updates to the
> ControlInfoMap over the IPC mechanism, but I don't think this is
> critical path, and it's simpler to send the whole updated map - so:
>
>
> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
>
> >         return 0;
> >  }
> >
> > diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> > index d980c1a71dd8..4596f2babcea 100644
> > --- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> > +++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> > @@ -940,6 +940,9 @@ int PipelineHandlerRPi::configure(Camera *camera,
> CameraConfiguration *config)
> >         /* Store the mode sensitivity for the application. */
> >         data->properties_.set(properties::SensorSensitivity,
> result.modeSensitivity);
> >
> > +       /* Update the controls that the Raspberry Pi IPA can handle. */
> > +       data->controlInfo_ = result.controlInfo;
> > +
> >         /* Setup the Video Mux/Bridge entities. */
> >         for (auto &[device, link] : data->bridgeDevices_) {
> >                 /*
> > --
> > 2.25.1
> >
>
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