[libcamera-devel] [PATCH v2 2/4] ipa: raspberrypi: Limit the calculated vblank based on the sensor mode
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Tue Jan 26 11:01:03 CET 2021
Hi Naush,
Thank you for the patch.
On Sun, Jan 24, 2021 at 02:05:04PM +0000, Naushir Patuck wrote:
> The existing framerate/vblank calculations did not account for the
> sensor mode limits. This commit extracts vblank limits from the sensor
> v4l2 controls, and stores it in the camera modes structure.
>
> Exposure and vblank value calculations now use values clamped to the
> sensor mode limits. The libcamera::controls::FrameDurations metadata
> return values now reflect the minimum and maximum after clamping.
>
> Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
> Reviewed-by: David Plowman <david.plowman at raspberrypi.com>
> ---
> src/ipa/raspberrypi/cam_helper.cpp | 16 +++---
> src/ipa/raspberrypi/cam_helper.hpp | 5 +-
> src/ipa/raspberrypi/cam_helper_imx219.cpp | 6 +--
> src/ipa/raspberrypi/cam_helper_imx477.cpp | 4 +-
> src/ipa/raspberrypi/cam_helper_ov5647.cpp | 4 +-
> src/ipa/raspberrypi/controller/camera_mode.h | 2 +
> src/ipa/raspberrypi/raspberrypi.cpp | 51 ++++++++++++++------
> 7 files changed, 49 insertions(+), 39 deletions(-)
>
> diff --git a/src/ipa/raspberrypi/cam_helper.cpp b/src/ipa/raspberrypi/cam_helper.cpp
> index b7b8faf09c69..3e17255737b2 100644
> --- a/src/ipa/raspberrypi/cam_helper.cpp
> +++ b/src/ipa/raspberrypi/cam_helper.cpp
> @@ -34,9 +34,8 @@ CamHelper *CamHelper::Create(std::string const &cam_name)
> return nullptr;
> }
>
> -CamHelper::CamHelper(MdParser *parser, unsigned int maxFrameLength,
> - unsigned int frameIntegrationDiff)
> - : parser_(parser), initialized_(false), maxFrameLength_(maxFrameLength),
> +CamHelper::CamHelper(MdParser *parser, unsigned int frameIntegrationDiff)
> + : parser_(parser), initialized_(false),
> frameIntegrationDiff_(frameIntegrationDiff)
> {
> }
> @@ -67,13 +66,12 @@ uint32_t CamHelper::GetVBlanking(double &exposure, double minFrameDuration,
> assert(initialized_);
>
> /*
> - * Clamp frame length by the frame duration range and the maximum allowable
> - * value in the sensor, given by maxFrameLength_.
> + * minFrameDuration and maxFrameDuration will have been clamped to the
Maybe "minFrameDuration and maxFrameDuration are clamped by the caller
based on the limits for the active sensor mode" to make clear who is
responsible for clamping those values ?
> + * maximum allowable values in the sensor for this mode.
> */
> - frameLengthMin = std::clamp<uint32_t>(1e3 * minFrameDuration / mode_.line_length,
> - mode_.height, maxFrameLength_);
> - frameLengthMax = std::clamp<uint32_t>(1e3 * maxFrameDuration / mode_.line_length,
> - mode_.height, maxFrameLength_);
> + frameLengthMin = 1e3 * minFrameDuration / mode_.line_length;
> + frameLengthMax = 1e3 * maxFrameDuration / mode_.line_length;
> +
> /*
> * Limit the exposure to the maximum frame duration requested, and
> * re-calculate if it has been clipped.
> diff --git a/src/ipa/raspberrypi/cam_helper.hpp b/src/ipa/raspberrypi/cam_helper.hpp
> index b1739a57e342..14d70112cb62 100644
> --- a/src/ipa/raspberrypi/cam_helper.hpp
> +++ b/src/ipa/raspberrypi/cam_helper.hpp
> @@ -62,8 +62,7 @@ class CamHelper
> {
> public:
> static CamHelper *Create(std::string const &cam_name);
> - CamHelper(MdParser *parser, unsigned int maxFrameLength,
> - unsigned int frameIntegrationDiff);
> + CamHelper(MdParser *parser, unsigned int frameIntegrationDiff);
> virtual ~CamHelper();
> void SetCameraMode(const CameraMode &mode);
> MdParser &Parser() const { return *parser_; }
> @@ -86,8 +85,6 @@ protected:
>
> private:
> bool initialized_;
> - /* Largest possible frame length, in units of lines. */
> - unsigned int maxFrameLength_;
> /*
> * Smallest difference between the frame length and integration time,
> * in units of lines.
> diff --git a/src/ipa/raspberrypi/cam_helper_imx219.cpp b/src/ipa/raspberrypi/cam_helper_imx219.cpp
> index 8688ec091c44..95b8e698fe3b 100644
> --- a/src/ipa/raspberrypi/cam_helper_imx219.cpp
> +++ b/src/ipa/raspberrypi/cam_helper_imx219.cpp
> @@ -56,15 +56,13 @@ private:
> * in units of lines.
> */
> static constexpr int frameIntegrationDiff = 4;
> - /* Largest possible frame length, in units of lines. */
> - static constexpr int maxFrameLength = 0xffff;
> };
>
> CamHelperImx219::CamHelperImx219()
> #if ENABLE_EMBEDDED_DATA
> - : CamHelper(new MdParserImx219(), maxFrameLength, frameIntegrationDiff)
> + : CamHelper(new MdParserImx219(), frameIntegrationDiff)
> #else
> - : CamHelper(new MdParserRPi(), maxFrameLength, frameIntegrationDiff)
> + : CamHelper(new MdParserRPi(), frameIntegrationDiff)
> #endif
> {
> }
> diff --git a/src/ipa/raspberrypi/cam_helper_imx477.cpp b/src/ipa/raspberrypi/cam_helper_imx477.cpp
> index 5396131003f1..eaa7be16d20e 100644
> --- a/src/ipa/raspberrypi/cam_helper_imx477.cpp
> +++ b/src/ipa/raspberrypi/cam_helper_imx477.cpp
> @@ -45,12 +45,10 @@ private:
> * in units of lines.
> */
> static constexpr int frameIntegrationDiff = 22;
> - /* Largest possible frame length, in units of lines. */
> - static constexpr int maxFrameLength = 0xffdc;
> };
>
> CamHelperImx477::CamHelperImx477()
> - : CamHelper(new MdParserImx477(), maxFrameLength, frameIntegrationDiff)
> + : CamHelper(new MdParserImx477(), frameIntegrationDiff)
> {
> }
>
> diff --git a/src/ipa/raspberrypi/cam_helper_ov5647.cpp b/src/ipa/raspberrypi/cam_helper_ov5647.cpp
> index 2bd8a754f133..a7f417324048 100644
> --- a/src/ipa/raspberrypi/cam_helper_ov5647.cpp
> +++ b/src/ipa/raspberrypi/cam_helper_ov5647.cpp
> @@ -30,8 +30,6 @@ private:
> * in units of lines.
> */
> static constexpr int frameIntegrationDiff = 4;
> - /* Largest possible frame length, in units of lines. */
> - static constexpr int maxFrameLength = 0xffff;
> };
>
> /*
> @@ -40,7 +38,7 @@ private:
> */
>
> CamHelperOv5647::CamHelperOv5647()
> - : CamHelper(new MdParserRPi(), maxFrameLength, frameIntegrationDiff)
> + : CamHelper(new MdParserRPi(), frameIntegrationDiff)
> {
> }
>
> diff --git a/src/ipa/raspberrypi/controller/camera_mode.h b/src/ipa/raspberrypi/controller/camera_mode.h
> index 920f11beb0b0..3baeadaca076 100644
> --- a/src/ipa/raspberrypi/controller/camera_mode.h
> +++ b/src/ipa/raspberrypi/controller/camera_mode.h
> @@ -37,6 +37,8 @@ struct CameraMode {
> double line_length;
> // any camera transform *not* reflected already in the camera tuning
> libcamera::Transform transform;
> + // minimum and maximum vblanking limits for this mode
> + uint32_t vblank_min, vblank_max;
> };
>
> #ifdef __cplusplus
> diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
> index 5ccc7a6551f5..30ba9aef9d97 100644
> --- a/src/ipa/raspberrypi/raspberrypi.cpp
> +++ b/src/ipa/raspberrypi/raspberrypi.cpp
> @@ -102,6 +102,7 @@ private:
> void reportMetadata();
> bool parseEmbeddedData(unsigned int bufferId, struct DeviceStatus &deviceStatus);
> void processStats(unsigned int bufferId);
> + void applyFrameDurations(double minFrameDuration, double maxFrameDuration);
> void applyAGC(const struct AgcStatus *agcStatus, ControlList &ctrls);
> void applyAWB(const struct AwbStatus *awbStatus, ControlList &ctrls);
> void applyDG(const struct AgcStatus *dgStatus, ControlList &ctrls);
> @@ -279,6 +280,14 @@ void IPARPi::setMode(const CameraSensorInfo &sensorInfo)
> * the line length in pixels and the pixel rate.
> */
> mode_.line_length = 1e9 * sensorInfo.lineLength / sensorInfo.pixelRate;
> +
> + /*
> + * Set the vertical blanking (frame duration) limits for the mode to
> + * ensure exposure and framerate calculations are clipped appropriately.
> + */
> + const auto itVblank = sensorCtrls_.find(V4L2_CID_VBLANK);
> + mode_.vblank_min = itVblank->second.min().get<int32_t>();
> + mode_.vblank_max = itVblank->second.max().get<int32_t>();
The trouble here is that sensorCtrls_ will not be updated after the
sensor configuration has changed. It comes from the
V4L2Device::controls() call in RPiCameraData::configureIPA(), and that
function returns a cached copy.
I really dislike the fact that V4L2 provides us with a control whose
limits change when the analog crop rectangle height changes, while the
sensors usually have a fixed vertical total size limit. Wouldn't it be
better to base the code on the vertical total size limit in libcamera,
instead of vertical blanking ? We would still have the issue of
retrieving this value, and I can see multiple options:
- Compute it once at initialization from vblank limits + analog crop
- Extend V4L2 with a new vertical total size control and use it (that
will be more work as we need to synchronize with the kernel changes)
- Hardcode the value in a sensor database in libcamera, bypassing the
kernel completly
One question that I'm not sure I can answer by myself is whether we can
rely on the vertical total size limits being constant.
> }
>
> void IPARPi::configure(const CameraSensorInfo &sensorInfo,
> @@ -384,8 +393,8 @@ void IPARPi::configure(const CameraSensorInfo &sensorInfo,
> controller_.Initialise();
> controllerInit_ = true;
>
> - minFrameDuration_ = defaultMinFrameDuration;
> - maxFrameDuration_ = defaultMaxFrameDuration;
> + /* Supply initial values for frame durations. */
> + applyFrameDurations(defaultMinFrameDuration, defaultMaxFrameDuration);
>
> /* Supply initial values for gain and exposure. */
> ControlList ctrls(sensorCtrls_);
> @@ -819,20 +828,7 @@ void IPARPi::queueRequest(const ControlList &controls)
>
> case controls::FRAME_DURATIONS: {
> auto frameDurations = ctrl.second.get<Span<const int64_t>>();
> -
> - /* This will be applied once AGC recalculations occur. */
> - minFrameDuration_ = frameDurations[0] ? frameDurations[0] : defaultMinFrameDuration;
> - maxFrameDuration_ = frameDurations[1] ? frameDurations[1] : defaultMaxFrameDuration;
> - maxFrameDuration_ = std::max(maxFrameDuration_, minFrameDuration_);
> -
> - /*
> - * \todo The values returned in the metadata below must be
> - * correctly clipped by what the sensor mode supports and
> - * what the AGC exposure mode or manual shutter speed limits
> - */
> - libcameraMetadata_.set(controls::FrameDurations,
> - { static_cast<int64_t>(minFrameDuration_),
> - static_cast<int64_t>(maxFrameDuration_) });
> + applyFrameDurations(frameDurations[0], frameDurations[1]);
> break;
> }
>
> @@ -991,6 +987,29 @@ void IPARPi::applyAWB(const struct AwbStatus *awbStatus, ControlList &ctrls)
> static_cast<int32_t>(awbStatus->gain_b * 1000));
> }
>
> +void IPARPi::applyFrameDurations(double minFrameDuration, double maxFrameDuration)
> +{
> + const double minSensorFrameDuration = 1e-3 * (mode_.vblank_min + mode_.height) *
> + mode_.line_length;
> + const double maxSensorFrameDuration = 1e-3 * (mode_.vblank_max + mode_.height) *
> + mode_.line_length;
> + /*
> + * This will only be applied once AGC recalculations occur.
> + * The values may be clamped based on the sensor mode capabilities as well.
> + */
> + minFrameDuration_ = minFrameDuration ? minFrameDuration : defaultMaxFrameDuration;
> + maxFrameDuration_ = maxFrameDuration ? maxFrameDuration : defaultMinFrameDuration;
> + minFrameDuration_ = std::clamp(minFrameDuration_,
> + minSensorFrameDuration, maxSensorFrameDuration);
> + maxFrameDuration_ = std::clamp(maxFrameDuration_,
> + minSensorFrameDuration, maxSensorFrameDuration);
> +
> + /* Return the validated limits out though metadata. */
> + libcameraMetadata_.set(controls::FrameDurations,
> + { static_cast<int64_t>(minFrameDuration_),
> + static_cast<int64_t>(maxFrameDuration_) });
> +}
> +
> void IPARPi::applyAGC(const struct AgcStatus *agcStatus, ControlList &ctrls)
> {
--
Regards,
Laurent Pinchart
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