[libcamera-devel] [PATCH v2] libcamera: ipu3: Add rotation to ipu3 pipeline

[Fabian Wüthrich]

Hi Jacopo,

I've just got the message that my driver needs to be fixed ^^

I like this change as it transparently states the requirements.

On 18.01.21 11:06, Jacopo Mondi wrote:
> Hi Fabian,
> 
> On Sat, Jan 16, 2021 at 04:02:58PM +0100, Fabian Wüthrich wrote:
>> Use the same transformation logic as in the raspberry pipeline to
>> implement rotations in the ipu3 pipeline.
>>
>> Tested on a Surface Book 2 with an experimental driver for OV5693.
>>
>> Signed-off-by: Fabian Wüthrich <me at fabwu.ch>
>> ---
>> Changes in v2:
>>  - Cache rotationTransform in CameraData
>>  - Use separate controls for sensor
>>
>>  src/libcamera/pipeline/ipu3/ipu3.cpp | 81 +++++++++++++++++++++++++++-
>>  1 file changed, 79 insertions(+), 2 deletions(-)
>>
>> diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
>> index 73304ea7..8db5f2f1 100644
>> --- a/src/libcamera/pipeline/ipu3/ipu3.cpp
>> +++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
>> @@ -14,6 +14,7 @@
>>  #include <libcamera/camera.h>
>>  #include <libcamera/control_ids.h>
>>  #include <libcamera/formats.h>
>> +#include <libcamera/property_ids.h>
>>  #include <libcamera/request.h>
>>  #include <libcamera/stream.h>
>>
>> @@ -62,6 +63,15 @@ public:
>>  	Stream outStream_;
>>  	Stream vfStream_;
>>  	Stream rawStream_;
>> +
>> +	/* Save transformation given by the sensor rotation */
>> +	Transform rotationTransform_;
>> +
>> +	/*
>> +	 * Manage horizontal and vertical flips supported (or not) by the
>> +	 * sensor.
>> +	 */
>> +	bool supportsFlips_;
>>  };
>>
>>  class IPU3CameraConfiguration : public CameraConfiguration
>> @@ -74,6 +84,9 @@ public:
>>  	const StreamConfiguration &cio2Format() const { return cio2Configuration_; }
>>  	const ImgUDevice::PipeConfig imguConfig() const { return pipeConfig_; }
>>
>> +	/* Cache the combinedTransform_ that will be applied to the sensor */
>> +	Transform combinedTransform_;
>> +
>>  private:
>>  	/*
>>  	 * The IPU3CameraData instance is guaranteed to be valid as long as the
>> @@ -143,11 +156,49 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
>>  	if (config_.empty())
>>  		return Invalid;
>>
>> -	if (transform != Transform::Identity) {
>> -		transform = Transform::Identity;
>> +	Transform combined = transform * data_->rotationTransform_;
>> +
>> +	/*
>> +	 * We combine the platform and user transform, but must "adjust away"
>> +	 * any combined result that includes a transposition, as we can't do those.
>> +	 * In this case, flipping only the transpose bit is helpful to
>> +	 * applications - they either get the transform they requested, or have
>> +	 * to do a simple transpose themselves (they don't have to worry about
>> +	 * the other possible cases).
>> +	 */
>> +	if (!!(combined & Transform::Transpose)) {
>> +		/*
>> +		 * Flipping the transpose bit in "transform" flips it in the
>> +		 * combined result too (as it's the last thing that happens),
>> +		 * which is of course clearing it.
>> +		 */
>> +		transform ^= Transform::Transpose;
>> +		combined &= ~Transform::Transpose;
>>  		status = Adjusted;
>>  	}
>>
>> +	/*
>> +	 * We also check if the sensor doesn't do h/vflips at all, in which
>> +	 * case we clear them, and the application will have to do everything.
>> +	 */
>> +	if (!data_->supportsFlips_ && !!combined) {
>> +		/*
>> +		 * If the sensor can do no transforms, then combined must be
>> +		 * changed to the identity. The only user transform that gives
>> +		 * rise to this is the inverse of the rotation. (Recall that
>> +		 * combined = transform * rotationTransform.)
>> +		 */
>> +		transform = -data_->rotationTransform_;
>> +		combined = Transform::Identity;
>> +		status = Adjusted;
>> +	}
>> +
>> +	/*
>> +	 * Store the final combined transform that configure() will need to
>> +	 * apply to the sensor to save us working it out again.
>> +	 */
>> +	combinedTransform_ = combined;
>> +
>>  	/* Cap the number of entries to the available streams. */
>>  	if (config_.size() > IPU3_MAX_STREAMS) {
>>  		config_.resize(IPU3_MAX_STREAMS);
>> @@ -540,6 +591,19 @@ int PipelineHandlerIPU3::configure(Camera *camera, CameraConfiguration *c)
>>  		return ret;
>>  	}
>>
>> +	/*
>> +	 * Configure the H/V flip controls based on the combination of
>> +	 * the sensor and user transform.
>> +	 */
>> +	if (data->supportsFlips_) {
>> +		ControlList sensor_ctrls(cio2->sensor()->controls());
>> +		sensor_ctrls.set(V4L2_CID_HFLIP,
>> +				 static_cast<int32_t>(!!(config->combinedTransform_ & Transform::HFlip)));
>> +		sensor_ctrls.set(V4L2_CID_VFLIP,
>> +				 static_cast<int32_t>(!!(config->combinedTransform_ & Transform::VFlip)));
>> +		cio2->sensor()->setControls(&sensor_ctrls);
>> +	}
>> +
>>  	return 0;
>>  }
>>
>> @@ -775,9 +839,22 @@ int PipelineHandlerIPU3::registerCameras()
>>  		/* Initialize the camera properties. */
>>  		data->properties_ = cio2->sensor()->properties();
>>
>> +		/* Convert the sensor rotation to a transformation */
>> +		int32_t rotation = data->properties_.get(properties::Rotation);
> 
> There's no guarantee the CameraSensor class register the Rotation
> property. It was defaulted to 0 if the information was not available
> from the firmware interface.
> 
> It is now not anymore (a very recent change, sorry)
> https://git.libcamera.org/libcamera/libcamera.git/commit/?id=c35123e6f91b6269cf6f5ae9216aeccebc545c75
> 
> Not sure what would be best, default to 0 in each pipeline handler
> that need that information ?
> 

Yes I can do that. Should I post a patch for the raspberry pipeline as well?

>> +		bool success;
>> +		data->rotationTransform_ = transformFromRotation(rotation, &success);
>> +		if (!success)
>> +			LOG(IPU3, Warning) << "Invalid rotation of " << rotation << " degrees - ignoring";
>> +
>>  		/* Initialze the camera controls. */
>>  		data->controlInfo_ = IPU3Controls;
>>
>> +		ControlList ctrls = cio2->sensor()->getControls({ V4L2_CID_HFLIP });
>> +		if (!ctrls.empty()) {
>> +			/* We assume it will support vflips too... */
>> +			data->supportsFlips_ = true;
>> +		}
>> +
>>  		/**
>>  		 * \todo Dynamically assign ImgU and output devices to each
>>  		 * stream and camera; as of now, limit support to two cameras
>> --
>> 2.30.0
>>