[PATCH v3 5/6] libcamera: camera_sensor_properties: Add sensor control delays

Laurent Pinchart laurent.pinchart at ideasonboard.com
Mon Nov 18 02:36:53 CET 2024


Hi Dan,

On Fri, Nov 15, 2024 at 01:35:54PM +0000, Daniel Scally wrote:
> On 15/11/2024 12:10, Kieran Bingham wrote:
> > Quoting Daniel Scally (2024-11-15 07:46:27)
> >> Add properties covering the sensor control application delays to both
> >> the static CameraSensorProperties definitions. The values used are the
> >> defaults that're in use across the library, with deviations from that

I had never seen "that're" before.

> >> taken from Raspberry Pi's CamHelper class definitions.
> >>
> >> Signed-off-by: Daniel Scally <dan.scally at ideasonboard.com>
> >> ---
> >> Changes in v3:
> >>
> >>          - Rebased on top of the CameraSensorFactory introduction
> >>          - Some rephrasing
> >>          - Defined the sensorDelays member as empty where Raspberry Pi didn't
> >>            have any specific values. Check for the empty struct in
> >>            getSensorDelays() and return the defaults from there with a warning.
> >
> > Sounds resonable to me.
> >
> >> Changes in v2:
> >>
> >>          - Rather than adding the delays to the properties ControlList, added a
> >>            new function in CameraSensor that allows PipelineHandlers to retreive
> >>            the delay values.
> >>
> >>   include/libcamera/internal/camera_sensor.h    |  2 +
> >>   .../internal/camera_sensor_properties.h       |  9 +++
> >>   src/libcamera/sensor/camera_sensor.cpp        | 13 +++
> >>   src/libcamera/sensor/camera_sensor_legacy.cpp | 33 ++++++++
> >>   .../sensor/camera_sensor_properties.cpp       | 79 +++++++++++++++++++
> >>   5 files changed, 136 insertions(+)
> >>
> >> diff --git a/include/libcamera/internal/camera_sensor.h b/include/libcamera/internal/camera_sensor.h
> >> index 8aafd82e..a9b2d494 100644
> >> --- a/include/libcamera/internal/camera_sensor.h
> >> +++ b/include/libcamera/internal/camera_sensor.h
> >> @@ -73,6 +73,8 @@ public:
> >>          virtual const std::vector<controls::draft::TestPatternModeEnum> &
> >>          testPatternModes() const = 0;
> >>          virtual int setTestPatternMode(controls::draft::TestPatternModeEnum mode) = 0;
> >> +       virtual void getSensorDelays(uint8_t &exposureDelay, uint8_t &gainDelay,
> >> +                                    uint8_t &vblankDelay, uint8_t &hblankDelay) = 0;
> >
> > Could/Should this return a const pointer to a struct SensorDelays now ?
>
> Yeah maybe...that would add a requirement for the struct to be available to CameraSensor (which is a 
> Factory class now) - I don't really have any strong feelings either way, so as long as that's fine 
> then I'll make the change.

I think it would make the API nicer.

> >>   };
> >>   
> >>   class CameraSensorFactoryBase
> >> diff --git a/include/libcamera/internal/camera_sensor_properties.h b/include/libcamera/internal/camera_sensor_properties.h
> >> index 480ac121..56d5c15d 100644
> >> --- a/include/libcamera/internal/camera_sensor_properties.h
> >> +++ b/include/libcamera/internal/camera_sensor_properties.h
> >> @@ -10,6 +10,8 @@
> >>   #include <map>
> >>   #include <string>
> >>   
> >> +#include <stdint.h>

stdint.h should go just before string, we mix the C and C++ headers.

> >> +
> >>   #include <libcamera/control_ids.h>
> >>   #include <libcamera/geometry.h>
> >>   
> >> @@ -20,6 +22,13 @@ struct CameraSensorProperties {
> >>   
> >>          Size unitCellSize;
> >>          std::map<controls::draft::TestPatternModeEnum, int32_t> testPatternModes;
> >> +
> >> +       struct {
> >> +               uint8_t exposureDelay;
> >> +               uint8_t gainDelay;
> >> +               uint8_t vblankDelay;
> >> +               uint8_t hblankDelay;
> >> +       } sensorDelays;
> >>   };
> >>   
> >>   } /* namespace libcamera */
> >> diff --git a/src/libcamera/sensor/camera_sensor.cpp b/src/libcamera/sensor/camera_sensor.cpp
> >> index 54cf98b2..61420873 100644
> >> --- a/src/libcamera/sensor/camera_sensor.cpp
> >> +++ b/src/libcamera/sensor/camera_sensor.cpp
> >> @@ -336,6 +336,19 @@ CameraSensor::~CameraSensor() = default;
> >>    * pattern mode for every frame thus incurs no performance penalty.
> >>    */
> >>   
> >> +/**
> >> + * \fn CameraSensor::getSensorDelays()

We don't usually prefix getters with "get".

> >> + * \brief Fetch the sensor delay values
> >> + * \param[out] exposureDelay The exposure delay
> >> + * \param[out] gainDelay The analogue gain delay
> >> + * \param[out] vblankDelay The vblank delay
> >> + * \param[out] hblankDelay The hblank delay
> >> + *
> >> + * This function fills in sensor control delays for pipeline handlers to use to
> >> + * inform the DelayedControls. If no static properties are available it fills in
> >> + * some widely applicable default values.

We need to return some default values until all sensors provide the
information we need, but I wouldn't call those "widely applicable
default values". It makes it sound those defaults will have a high
chance of working, while that's not specifically the case.

> >> + */
> >> +
> >>   /**
> >>    * \class CameraSensorFactoryBase
> >>    * \brief Base class for camera sensor factories
> >> diff --git a/src/libcamera/sensor/camera_sensor_legacy.cpp b/src/libcamera/sensor/camera_sensor_legacy.cpp
> >> index a9b15c03..84972f02 100644
> >> --- a/src/libcamera/sensor/camera_sensor_legacy.cpp
> >> +++ b/src/libcamera/sensor/camera_sensor_legacy.cpp
> >> @@ -95,6 +95,8 @@ public:
> >>          const std::vector<controls::draft::TestPatternModeEnum> &
> >>          testPatternModes() const override { return testPatternModes_; }
> >>          int setTestPatternMode(controls::draft::TestPatternModeEnum mode) override;
> >> +       void getSensorDelays(uint8_t &exposureDelay, uint8_t &gainDelay,
> >> +                            uint8_t &vblankDelay, uint8_t &hblankDelay) override;
> >>   
> >>   protected:
> >>          std::string logPrefix() const override;
> >> @@ -482,6 +484,37 @@ void CameraSensorLegacy::initStaticProperties()
> >>          initTestPatternModes();
> >>   }
> >>   
> >> +void CameraSensorLegacy::getSensorDelays(uint8_t &exposureDelay, uint8_t &gainDelay,
> >> +                                        uint8_t &vblankDelay, uint8_t &hblankDelay)
> >> +{
> >> +
> >> +       /*
> >> +        * These defaults are applicable to many sensors, however more specific
> >> +        * values can be added to the CameraSensorProperties for a sensor if
> >> +        * required.
> >> +        */
> >> +       if (!staticProps_ ||
> >> +           (!staticProps_->sensorDelays.exposureDelay &&
> >> +            !staticProps_->sensorDelays.gainDelay &&
> >> +            !staticProps_->sensorDelays.vblankDelay &&
> >> +            !staticProps_->sensorDelays.hblankDelay)) {
> >> +               LOG(CameraSensor, Warning)
> >> +                       << "No sensor delays found in static properties. "
> >> +                          "Assuming unverified defaults.";

Here the lack of sensor-specific values is reported with a more
appropriate seriousness. Let's update the comments to match.

> >> +
> >> +               exposureDelay = 2;
> >> +               gainDelay = 1;
> >> +               vblankDelay = 2;
> >> +               hblankDelay = 2;
> >> +               return;
> >> +       }
> >> +
> >> +       exposureDelay = staticProps_->sensorDelays.exposureDelay;
> >> +       gainDelay = staticProps_->sensorDelays.gainDelay;
> >> +       vblankDelay = staticProps_->sensorDelays.vblankDelay;
> >> +       hblankDelay = staticProps_->sensorDelays.hblankDelay;
> >
> > Which would make this just
> >
> > 	return staticProps_->sensorDelays;
> >
> >> +}
> >
> > I'm glad this function prints a warning!
> >
> >> +
> >>   void CameraSensorLegacy::initTestPatternModes()
> >>   {
> >>          const auto &v4l2TestPattern = controls().find(V4L2_CID_TEST_PATTERN);
> >> diff --git a/src/libcamera/sensor/camera_sensor_properties.cpp b/src/libcamera/sensor/camera_sensor_properties.cpp
> >> index 6d4136d0..6dda7ba9 100644
> >> --- a/src/libcamera/sensor/camera_sensor_properties.cpp
> >> +++ b/src/libcamera/sensor/camera_sensor_properties.cpp
> >> @@ -41,6 +41,13 @@ LOG_DEFINE_CATEGORY(CameraSensorProperties)
> >>    * \brief Map that associates the TestPattern control value with the indexes of
> >>    * the corresponding sensor test pattern modes as returned by
> >>    * V4L2_CID_TEST_PATTERN.
> >> + *
> >> + * \var CameraSensorProperties::sensorDelays
> >> + * \brief Holds the delays, expressed in number of frames, between the time a
> >> + * control is applied to the sensor and the time it actually takes effect.
> >> + * Delays are recorded for the exposure time, analogue gain, vertical and
> >> + * horizontal blanking. These values may be defined as empty, in which case the
> >> + * CameraSensor derivative should provide default values.

A \brief should be brief :-) Make it a single short sentence, and you
can add more information in the body of the documentation.

> >>    */
> >>   
> >>   /**
> >> @@ -60,6 +67,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeColorBars, 2 },
> >>                                  { controls::draft::TestPatternModeColorBarsFadeToGray, 3 },
> >>                          },
> >> +                       .sensorDelays = { },

The AR0144 has a 2 frames delay for all parameters. Assuming that "2
frames delay" means that parameters set during frame N will take effect
for frame N+2 (so a delay of 0 means the parameter is applied
immediately to the current frame). Maybe this should be documented more
clearly above.

Note that the sensor can also be programmed to apply a one frame delay
instead of two frames for the analog gain. The value is therefore
driver-dependent, and could even be changed dynamically. That's
something to worry about later.

> >>                  } },
> >>                  { "ar0521", {
> >>                          .unitCellSize = { 2200, 2200 },
> >> @@ -69,6 +77,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeColorBars, 2 },
> >>                                  { controls::draft::TestPatternModeColorBarsFadeToGray, 3 },
> >>                          },
> >> +                       .sensorDelays = { },

The AR0521 will be interesting. The exposure time has a 2 frames delay,
while the analog gain will have a 1 frame delay if it is set alone, and
a 2 frames delay if the exposure time is also set during the same frame.
This is something we should consider when we'll develop a tool to
measure delays.

The sensor can be configured to have a fixed 2 frames delay for the
analog gain, but that's not how the driver currently configures it.

The delay for the blanking values doesn't seem to be documented.

> >>                  } },
> >>                  { "hi846", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -87,6 +96,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * 9: "Resolution Pattern"
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "imx214", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -97,6 +107,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeColorBarsFadeToGray, 3 },
> >>                                  { controls::draft::TestPatternModePn9, 4 },
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "imx219", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -107,6 +118,12 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeColorBarsFadeToGray, 3 },
> >>                                  { controls::draft::TestPatternModePn9, 4 },
> >>                          },
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 1,
> >> +                               .vblankDelay = 2,
> >> +                               .hblankDelay = 2
> >> +                       },
> >>                  } },
> >>                  { "imx258", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -117,34 +134,62 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeColorBarsFadeToGray, 3 },
> >>                                  { controls::draft::TestPatternModePn9, 4 },
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "imx283", {
> >>                          .unitCellSize = { 2400, 2400 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 2,
> >> +                               .hblankDelay = 2
> >> +                       },
> >>                  } },
> >>                  { "imx290", {
> >>                          .unitCellSize = { 2900, 2900 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 2,
> >> +                               .hblankDelay = 2
> >> +                       },
> >>                  } },
> >>                  { "imx296", {
> >>                          .unitCellSize = { 3450, 3450 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 2,
> >> +                               .hblankDelay = 2
> >> +                       },
> >>                  } },
> >>                  { "imx327", {
> >>                          .unitCellSize = { 2900, 2900 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "imx335", {
> >>                          .unitCellSize = { 2000, 2000 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "imx415", {
> >>                          .unitCellSize = { 1450, 1450 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "imx477", {
> >>                          .unitCellSize = { 1550, 1550 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 3,
> >> +                               .hblankDelay = 3
> >> +                       },
> >>                  } },
> >>                  { "imx519", {
> >>                          .unitCellSize = { 1220, 1220 },
> >> @@ -157,6 +202,12 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * these two patterns do not comply with MIPI CCS v1.1 (Section 10.1).
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 3,
> >> +                               .hblankDelay = 3
> >> +                       },
> >>                  } },
> >>                  { "imx708", {
> >>                          .unitCellSize = { 1400, 1400 },
> >> @@ -167,6 +218,12 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeColorBarsFadeToGray, 3 },
> >>                                  { controls::draft::TestPatternModePn9, 4 },
> >>                          },
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 3,
> >> +                               .hblankDelay = 3
> >> +                       },
> >>                  } },
> >>                  { "ov2685", {
> >>                          .unitCellSize = { 1750, 1750 },
> >> @@ -181,6 +238,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * 5: "Color Square"
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov2740", {
> >>                          .unitCellSize = { 1400, 1400 },
> >> @@ -188,6 +246,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeOff, 0 },
> >>                                  { controls::draft::TestPatternModeColorBars, 1},
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov4689", {
> >>                          .unitCellSize = { 2000, 2000 },
> >> @@ -201,6 +260,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * colorBarType2 and colorBarType3.
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov5640", {
> >>                          .unitCellSize = { 1400, 1400 },
> >> @@ -208,10 +268,17 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeOff, 0 },
> >>                                  { controls::draft::TestPatternModeColorBars, 1 },
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov5647", {
> >>                          .unitCellSize = { 1400, 1400 },
> >>                          .testPatternModes = {},
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 2,
> >> +                               .hblankDelay = 2
> >> +                       },
> >>                  } },
> >>                  { "ov5670", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -219,6 +286,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeOff, 0 },
> >>                                  { controls::draft::TestPatternModeColorBars, 1 },
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov5675", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -226,6 +294,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeOff, 0 },
> >>                                  { controls::draft::TestPatternModeColorBars, 1 },
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov5693", {
> >>                          .unitCellSize = { 1400, 1400 },
> >> @@ -238,6 +307,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * Rolling Bar".
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov64a40", {
> >>                          .unitCellSize = { 1008, 1008 },
> >> @@ -251,6 +321,12 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * 4: "Vertical Color Bar Type 4"
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = {
> >> +                               .exposureDelay = 2,
> >> +                               .gainDelay = 2,
> >> +                               .vblankDelay = 2,
> >> +                               .hblankDelay = 2
> >> +                       },
> >>                  } },
> >>                  { "ov8858", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -264,6 +340,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * 4: "Vertical Color Bar Type 4"
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov8865", {
> >>                          .unitCellSize = { 1400, 1400 },
> >> @@ -278,6 +355,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                   * 5: "Color squares with rolling bar"
> >>                                   */
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>                  { "ov13858", {
> >>                          .unitCellSize = { 1120, 1120 },
> >> @@ -285,6 +363,7 @@ const CameraSensorProperties *CameraSensorProperties::get(const std::string &sen
> >>                                  { controls::draft::TestPatternModeOff, 0 },
> >>                                  { controls::draft::TestPatternModeColorBars, 1 },
> >>                          },
> >> +                       .sensorDelays = { },
> >>                  } },
> >>          };
> >>   

-- 
Regards,

Laurent Pinchart


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