[PATCH v4 2/5] libcamera: converter: Add interface to support cropping capability
Umang Jain
umang.jain at ideasonboard.com
Wed Jul 3 05:28:53 CEST 2024
Hi Paul
On 02/07/24 6:06 pm, Paul Elder wrote:
> On Thu, Jun 27, 2024 at 07:16:53PM +0530, Umang Jain wrote:
>> If the converter has cropping capability, the interface should support it
>> by providing appropriate virtual functions. Provide Feature::Crop in
>> Feature enumeration for the same.
>>
>> Provide virtual setCrop() and getCropBounds() interfaces so that
>> the converter can implement their own cropping functionality.
>>
>> The V4L2M2MConverter implements these interfaces of the Converter
>> interface. Not all V4L2M2M converters will have cropping capability,
>> hence Feature::Crop should be set while construction for all those
>> converters.
>>
>> For implementing the getCropBounds(), V4L2VideoDevice needs
>> to be extended to support VIDIOC_G_SELECTION via
>> V4L2VideoDevice::getSelection().
>>
>> Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
>> ---
>> include/libcamera/internal/converter.h | 5 ++
>> .../internal/converter/converter_v4l2_m2m.h | 7 ++
>> include/libcamera/internal/v4l2_videodevice.h | 1 +
>> src/libcamera/converter.cpp | 35 ++++++++
>> .../converter/converter_v4l2_m2m.cpp | 85 +++++++++++++++++++
>> src/libcamera/v4l2_videodevice.cpp | 32 +++++++
>> 6 files changed, 165 insertions(+)
>>
>> diff --git a/include/libcamera/internal/converter.h b/include/libcamera/internal/converter.h
>> index 15bc7dca..deba75e3 100644
>> --- a/include/libcamera/internal/converter.h
>> +++ b/include/libcamera/internal/converter.h
>> @@ -14,6 +14,7 @@
>> #include <memory>
>> #include <string>
>> #include <tuple>
>> +#include <utility>
>> #include <vector>
>>
>> #include <libcamera/base/class.h>
>> @@ -35,6 +36,7 @@ class Converter
>> public:
>> enum class Feature {
>> None = (1 << 0),
>> + Crop = (1 << 1),
>> };
>>
>> using Features = Flags<Feature>;
>> @@ -63,6 +65,9 @@ public:
>> virtual int queueBuffers(FrameBuffer *input,
>> const std::map<const Stream *, FrameBuffer *> &outputs) = 0;
>>
>> + virtual int setCrop(const Stream *stream, Rectangle *rect);
>> + virtual std::pair<Rectangle, Rectangle> getCropBounds(const Stream *stream);
>> +
>> Signal<FrameBuffer *> inputBufferReady;
>> Signal<FrameBuffer *> outputBufferReady;
>>
>> diff --git a/include/libcamera/internal/converter/converter_v4l2_m2m.h b/include/libcamera/internal/converter/converter_v4l2_m2m.h
>> index 91701dbe..e97fbdd2 100644
>> --- a/include/libcamera/internal/converter/converter_v4l2_m2m.h
>> +++ b/include/libcamera/internal/converter/converter_v4l2_m2m.h
>> @@ -30,6 +30,7 @@ class Size;
>> class SizeRange;
>> class Stream;
>> struct StreamConfiguration;
>> +class Rectangle;
>> class V4L2M2MDevice;
>>
>> class V4L2M2MConverter : public Converter
>> @@ -57,6 +58,9 @@ public:
>> int queueBuffers(FrameBuffer *input,
>> const std::map<const Stream *, FrameBuffer *> &outputs);
>>
>> + int setCrop(const Stream *stream, Rectangle *rect);
>> + std::pair<Rectangle, Rectangle> getCropBounds(const Stream *stream);
>> +
>> private:
>> class V4L2M2MStream : protected Loggable
>> {
>> @@ -75,6 +79,9 @@ private:
>>
>> int queueBuffers(FrameBuffer *input, FrameBuffer *output);
>>
>> + int getSelection(unsigned int target, Rectangle *rect);
>> + int setSelection(unsigned int target, Rectangle *rect);
>> +
>> protected:
>> std::string logPrefix() const override;
>>
>> diff --git a/include/libcamera/internal/v4l2_videodevice.h b/include/libcamera/internal/v4l2_videodevice.h
>> index 9057be08..506d6a65 100644
>> --- a/include/libcamera/internal/v4l2_videodevice.h
>> +++ b/include/libcamera/internal/v4l2_videodevice.h
>> @@ -209,6 +209,7 @@ public:
>> Formats formats(uint32_t code = 0);
>>
>> int setSelection(unsigned int target, Rectangle *rect);
>> + int getSelection(unsigned int target, Rectangle *rect);
>>
>> int allocateBuffers(unsigned int count,
>> std::vector<std::unique_ptr<FrameBuffer>> *buffers);
>> diff --git a/src/libcamera/converter.cpp b/src/libcamera/converter.cpp
>> index 2dc7d984..19634e1c 100644
>> --- a/src/libcamera/converter.cpp
>> +++ b/src/libcamera/converter.cpp
>> @@ -39,6 +39,9 @@ LOG_DEFINE_CATEGORY(Converter)
>> * \brief Specify the features supported by the converter
>> * \var Converter::Feature::None
>> * \brief No extra features supported by the converter
>> + * \var Converter::Feature::Crop
>> + * \brief Cropping capability is supported by the converter
>> +
>> */
>>
>> /**
>> @@ -161,6 +164,38 @@ Converter::~Converter()
>> * \return 0 on success or a negative error code otherwise
>> */
>>
>> +/**
>> + * \brief Set the crop rectangle \a rect for \a stream
>> + * \param[in] stream Pointer to output stream
>> + * \param[inout] rect The crop rectangle to be applied
>> + *
>> + * Set the crop rectangle \a rect for \a stream provided the converter supports
>> + * cropping. The converter should have the Feature::Crop flag in this case.
>> + *
>> + * \return 0 on success or a negative error code otherwise
>> + */
>> +int Converter::setCrop([[maybe_unused]] const Stream *stream, [[maybe_unused]] Rectangle *rect)
>> +{
>> + return 0;
>> +}
>> +
>> +/**
>> + * \brief Get the crop bounds \a stream
>> + * \param[in] stream Pointer to output stream
>> + *
>> + * Get the minimum and maximum crop bounds for \a stream. The converter
>> + * should supporting cropping (Feature::Crop).
>> + *
>> + * \return A std::pair<Rectangle, Rectangle> containining minimum and maximum
>> + * crop bound respectively.
>> + */
>> +std::pair<Rectangle, Rectangle> Converter::getCropBounds([[maybe_unused]] const Stream *stream)
>> +{
>> + Rectangle rect;
>> +
>> + return { rect, rect };
>> +}
> These look strange to me... they seem to not to expected to ever be
> called... is there no way to keep them virtual and require them to be
> overridden by inheritors? Otherwise the implementations clearly imply
Do you mean I should make the getCropBounds() and setCrop() 'pure'
virtual functions (like the others in the converter interface) ? In that
case, all inherited class will need to provide a crop implementation
regardless they support the capability or not.
Currently, they are just virtual functions, and inherited ones are not
mandated to provide implementation. But the converter interface need to
give a its implementation in this case.
> "crop is not supported", and any application that does actually call
> these would end up with unexpected nops.
>
>> +
>> /**
>> * \var Converter::inputBufferReady
>> * \brief A signal emitted when the input frame buffer completes
>> diff --git a/src/libcamera/converter/converter_v4l2_m2m.cpp b/src/libcamera/converter/converter_v4l2_m2m.cpp
>> index 4aeb7dd9..4bb625e9 100644
>> --- a/src/libcamera/converter/converter_v4l2_m2m.cpp
>> +++ b/src/libcamera/converter/converter_v4l2_m2m.cpp
>> @@ -155,6 +155,24 @@ int V4L2M2MConverter::V4L2M2MStream::queueBuffers(FrameBuffer *input, FrameBuffe
>> return 0;
>> }
>>
>> +int V4L2M2MConverter::V4L2M2MStream::setSelection(unsigned int target, Rectangle *rect)
>> +{
>> + int ret = m2m_->output()->setSelection(target, rect);
>> + if (ret < 0)
>> + return ret;
>> +
>> + return 0;
>> +}
>> +
>> +int V4L2M2MConverter::V4L2M2MStream::getSelection(unsigned int target, Rectangle *rect)
>> +{
>> + int ret = m2m_->output()->getSelection(target, rect);
>> + if (ret < 0)
>> + return ret;
>> +
>> + return 0;
>> +}
>> +
>> std::string V4L2M2MConverter::V4L2M2MStream::logPrefix() const
>> {
>> return stream_->configuration().toString();
>> @@ -375,6 +393,69 @@ int V4L2M2MConverter::exportBuffers(const Stream *stream, unsigned int count,
>> return iter->second->exportBuffers(count, buffers);
>> }
>>
>> +/**
>> + * \copydoc libcamera::Converter::setCrop
>> + */
>> +int V4L2M2MConverter::setCrop(const Stream *stream, Rectangle *rect)
>> +{
>> + if (!(getFeatures() & Feature::Crop))
>> + return -ENOTSUP;
>> +
>> + auto iter = streams_.find(stream);
>> + if (iter == streams_.end())
>> + return -EINVAL;
>> +
>> + return iter->second->setSelection(V4L2_SEL_TGT_CROP, rect);
>> +}
>> +
>> +/**
>> + * \copydoc libcamera::Converter::getCropBounds
>> + */
>> +std::pair<Rectangle, Rectangle>
>> +V4L2M2MConverter::getCropBounds(const Stream *stream)
>> +{
>> + Rectangle minCrop;
>> + Rectangle maxCrop;
>> + int ret;
>> +
>> + auto iter = streams_.find(stream);
>> + if (iter == streams_.end())
>> + return {};
>> +
>> + if (!(getFeatures() & Feature::Crop)) {
>> + LOG(Converter, Error) << "Crop functionality is not supported";
>> + return {};
>> + }
>> +
>> + /* Get the maximum crop bound */
>> + ret = iter->second->getSelection(V4L2_SEL_TGT_CROP_BOUNDS, &maxCrop);
> Do you not need to set an astronomically large crop bound like the
> minimum one? Isn't it possible to simply use the size of the configured
> format?
Possibly. That would reduce a lot of code here as well (esp. the
introduction of G_SELECTION)
>
> Paul
>
>> + if (ret) {
>> + LOG(Converter, Error) << "Failed to query maximum crop bound";
>> + return {};
>> + }
>> +
>> + /*
>> + * Get the minimum crop bound by setting 1x1 crop rectangle. The returned
>> + * rectangle should be them minimum crop supported by the driver.
>> + */
>> + minCrop.width = 1;
>> + minCrop.height = 1;
>> + ret = setCrop(stream, &minCrop);
>> + if (ret) {
>> + LOG(Converter, Error) << "Failed to query minimum crop bound";
>> + return {};
>> + }
>> +
>> + /* Reset the crop rectangle to maximum */
>> + ret = setCrop(stream, &maxCrop);
>> + if (ret) {
>> + LOG(Converter, Error) << "Failed to reset the crop to " << maxCrop.toString();
>> + return {};
>> + }
>> +
>> + return { minCrop, maxCrop };
>> +}
>> +
>> /**
>> * \copydoc libcamera::Converter::start
>> */
>> @@ -448,6 +529,10 @@ int V4L2M2MConverter::queueBuffers(FrameBuffer *input,
>> return 0;
>> }
>>
>> +/*
>> + * \todo: This should be extended to include Feature::Flag to denote
>> + * what each converter supports feature-wise.
>> + */
>> static std::initializer_list<std::string> compatibles = {
>> "mtk-mdp",
>> "pxp",
>> diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
>> index 4947aa3d..dfbfae2c 100644
>> --- a/src/libcamera/v4l2_videodevice.cpp
>> +++ b/src/libcamera/v4l2_videodevice.cpp
>> @@ -1226,6 +1226,38 @@ int V4L2VideoDevice::setSelection(unsigned int target, Rectangle *rect)
>> return 0;
>> }
>>
>> +/**
>> + * \brief Get the selection rectangle \a rect for \a target
>> + * \param[in] target The selection target defined by the V4L2_SEL_TGT_* flags
>> + * \param[inout] rect The selection rectangle that has been queried
>> + *
>> + * \todo Define a V4L2SelectionTarget enum for the selection target
>> + *
>> + * \return 0 on success or a negative error code otherwise
>> + */
>> +int V4L2VideoDevice::getSelection(unsigned int target, Rectangle *rect)
>> +{
>> + struct v4l2_selection sel = {};
>> +
>> + sel.type = bufferType_;
>> + sel.target = target;
>> + sel.flags = 0;
>> +
>> + int ret = ioctl(VIDIOC_G_SELECTION, &sel);
>> + if (ret < 0) {
>> + LOG(V4L2, Error) << "Unable to get rectangle " << target
>> + << ": " << strerror(-ret);
>> + return ret;
>> + }
>> +
>> + rect->x = sel.r.left;
>> + rect->y = sel.r.top;
>> + rect->width = sel.r.width;
>> + rect->height = sel.r.height;
>> +
>> + return 0;
>> +}
>> +
>> int V4L2VideoDevice::requestBuffers(unsigned int count,
>> enum v4l2_memory memoryType)
>> {
>> --
>> 2.44.0
>>
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