[libcamera-devel] [PATCH v2 25/27] qcam: Use Image class to access pixel data

Laurent Pinchart laurent.pinchart at ideasonboard.com
Mon Sep 6 13:45:35 CEST 2021


Hi Jean-Michel,

On Mon, Sep 06, 2021 at 11:36:10AM +0200, Jean-Michel Hautbois wrote:
> On 06/09/2021 04:00, Laurent Pinchart wrote:
> > Replace the manual implementation of frame buffer mapping with the Image
> > class to improve code sharing. The ViewFinder API is updated to take an
> > Image pointer in the render() function to prepare for multi-planar
> > buffer support.
> > 
> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > ---
> >  src/qcam/main_window.cpp   | 31 ++++++++-----------------------
> >  src/qcam/main_window.h     |  4 ++--
> >  src/qcam/meson.build       |  1 +
> >  src/qcam/viewfinder.h      |  6 +++---
> >  src/qcam/viewfinder_gl.cpp |  7 ++++---
> >  src/qcam/viewfinder_gl.h   |  2 +-
> >  src/qcam/viewfinder_qt.cpp |  6 +++---
> >  src/qcam/viewfinder_qt.h   |  2 +-
> >  8 files changed, 23 insertions(+), 36 deletions(-)
> > 
> > diff --git a/src/qcam/main_window.cpp b/src/qcam/main_window.cpp
> > index 0a00b1001570..168dd5ce30e3 100644
> > --- a/src/qcam/main_window.cpp
> > +++ b/src/qcam/main_window.cpp
> > @@ -7,10 +7,9 @@
> >  
> >  #include "main_window.h"
> >  
> > +#include <assert.h>
> >  #include <iomanip>
> >  #include <string>
> > -#include <sys/mman.h>
> > -#include <unistd.h>
> >  
> >  #include <QComboBox>
> >  #include <QCoreApplication>
> > @@ -29,6 +28,7 @@
> >  #include <libcamera/camera_manager.h>
> >  #include <libcamera/version.h>
> >  
> > +#include "../cam/image.h"
> >  #include "dng_writer.h"
> >  #ifndef QT_NO_OPENGL
> >  #include "viewfinder_gl.h"
> > @@ -473,15 +473,10 @@ int MainWindow::startCapture()
> >  
> >  		for (const std::unique_ptr<FrameBuffer> &buffer : allocator_->buffers(stream)) {
> >  			/* Map memory buffers and cache the mappings. */
> > -			const FrameBuffer::Plane &plane = buffer->planes().front();
> > -			size_t length = lseek(plane.fd.fd(), 0, SEEK_END);
> > -			void *memory = mmap(NULL, length, PROT_READ, MAP_SHARED,
> > -					    plane.fd.fd(), 0);
> > -
> > -			mappedBuffers_[buffer.get()] = { static_cast<uint8_t *>(memory),
> > -							 plane.length };
> > -			planeData_[buffer.get()] = { static_cast<uint8_t *>(memory) + plane.offset,
> > -						     plane.length };
> > +			std::unique_ptr<Image> image =
> > +				Image::fromFrameBuffer(buffer.get(), Image::MapMode::ReadOnly);
> > +			assert(image != nullptr);
> > +			mappedBuffers_[buffer.get()] = std::move(image);
> >  
> >  			/* Store buffers on the free list. */
> >  			freeBuffers_[stream].enqueue(buffer.get());
> > @@ -543,12 +538,7 @@ error_disconnect:
> >  error:
> >  	requests_.clear();
> >  
> > -	for (auto &iter : mappedBuffers_) {
> > -		const Span<uint8_t> &buffer = iter.second;
> > -		munmap(buffer.data(), buffer.size());
> > -	}
> >  	mappedBuffers_.clear();
> > -	planeData_.clear();
> >  
> >  	freeBuffers_.clear();
> >  
> > @@ -580,12 +570,7 @@ void MainWindow::stopCapture()
> >  
> >  	camera_->requestCompleted.disconnect(this);
> >  
> > -	for (auto &iter : mappedBuffers_) {
> > -		const Span<uint8_t> &buffer = iter.second;
> > -		munmap(buffer.data(), buffer.size());
> > -	}
> >  	mappedBuffers_.clear();
> > -	planeData_.clear();
> >  
> >  	requests_.clear();
> >  	freeQueue_.clear();
> > @@ -682,7 +667,7 @@ void MainWindow::processRaw(FrameBuffer *buffer,
> >  							"DNG Files (*.dng)");
> >  
> >  	if (!filename.isEmpty()) {
> > -		uint8_t *memory = planeData_[buffer].data();
> > +		uint8_t *memory = mappedBuffers_[buffer]->data(0).data();
> >  		DNGWriter::write(filename.toStdString().c_str(), camera_.get(),
> >  				 rawStream_->configuration(), metadata, buffer,
> >  				 memory);
> > @@ -766,7 +751,7 @@ void MainWindow::processViewfinder(FrameBuffer *buffer)
> >  		<< "fps:" << Qt::fixed << qSetRealNumberPrecision(2) << fps;
> >  
> >  	/* Render the frame on the viewfinder. */
> > -	viewfinder_->render(buffer, planeData_[buffer]);
> > +	viewfinder_->render(buffer, mappedBuffers_[buffer].get());
> >  }
> >  
> >  void MainWindow::queueRequest(FrameBuffer *buffer)
> > diff --git a/src/qcam/main_window.h b/src/qcam/main_window.h
> > index 28244bca58b2..a16bea09eadc 100644
> > --- a/src/qcam/main_window.h
> > +++ b/src/qcam/main_window.h
> > @@ -34,6 +34,7 @@ using namespace libcamera;
> >  class QAction;
> >  class QComboBox;
> >  
> > +class Image;
> >  class HotplugEvent;
> >  
> >  enum {
> > @@ -106,8 +107,7 @@ private:
> >  	FrameBufferAllocator *allocator_;
> >  
> >  	std::unique_ptr<CameraConfiguration> config_;
> > -	std::map<FrameBuffer *, Span<uint8_t>> mappedBuffers_;
> > -	std::map<FrameBuffer *, Span<uint8_t>> planeData_;
> > +	std::map<FrameBuffer *, std::unique_ptr<Image>> mappedBuffers_;
> >  
> >  	/* Capture state, buffers queue and statistics */
> >  	bool isCapturing_;
> > diff --git a/src/qcam/meson.build b/src/qcam/meson.build
> > index 7d3621c93d41..c46f463130cd 100644
> > --- a/src/qcam/meson.build
> > +++ b/src/qcam/meson.build
> > @@ -15,6 +15,7 @@ endif
> >  qcam_enabled = true
> >  
> >  qcam_sources = files([
> > +    '../cam/image.cpp',
> >      '../cam/options.cpp',
> >      '../cam/stream_options.cpp',
> 
> I never realized we were referencing as much "../cam" !
> 
> >      'format_converter.cpp',
> > diff --git a/src/qcam/viewfinder.h b/src/qcam/viewfinder.h
> > index 42d40f1f33f0..fb462835fb5f 100644
> > --- a/src/qcam/viewfinder.h
> > +++ b/src/qcam/viewfinder.h
> > @@ -11,11 +11,11 @@
> >  #include <QList>
> >  #include <QSize>
> >  
> > -#include <libcamera/base/span.h>
> > -
> >  #include <libcamera/formats.h>
> >  #include <libcamera/framebuffer.h>
> >  
> > +class Image;
> > +
> >  class ViewFinder
> >  {
> >  public:
> > @@ -24,7 +24,7 @@ public:
> >  	virtual const QList<libcamera::PixelFormat> &nativeFormats() const = 0;
> >  
> >  	virtual int setFormat(const libcamera::PixelFormat &format, const QSize &size) = 0;
> > -	virtual void render(libcamera::FrameBuffer *buffer, libcamera::Span<uint8_t> mem) = 0;
> > +	virtual void render(libcamera::FrameBuffer *buffer, Image *image) = 0;
> >  	virtual void stop() = 0;
> >  
> >  	virtual QImage getCurrentImage() = 0;
> > diff --git a/src/qcam/viewfinder_gl.cpp b/src/qcam/viewfinder_gl.cpp
> > index d2ef036974f4..87e4fe03cb8d 100644
> > --- a/src/qcam/viewfinder_gl.cpp
> > +++ b/src/qcam/viewfinder_gl.cpp
> > @@ -13,6 +13,8 @@
> >  
> >  #include <libcamera/formats.h>
> >  
> > +#include "../cam/image.h"
> 
> Where should Image class be in the end, once stable enough ?

I expect it to move to include/libcamera/ then.

> Reviewed-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
>
> > +
> >  static const QList<libcamera::PixelFormat> supportedFormats{
> >  	/* YUV - packed (single plane) */
> >  	libcamera::formats::UYVY,
> > @@ -110,8 +112,7 @@ QImage ViewFinderGL::getCurrentImage()
> >  	return grabFramebuffer();
> >  }
> >  
> > -void ViewFinderGL::render(libcamera::FrameBuffer *buffer,
> > -			  libcamera::Span<uint8_t> mem)
> > +void ViewFinderGL::render(libcamera::FrameBuffer *buffer, Image *image)
> >  {
> >  	if (buffer->planes().size() != 1) {
> >  		qWarning() << "Multi-planar buffers are not supported";
> > @@ -121,7 +122,7 @@ void ViewFinderGL::render(libcamera::FrameBuffer *buffer,
> >  	if (buffer_)
> >  		renderComplete(buffer_);
> >  
> > -	data_ = mem.data();
> > +	data_ = image->data(0).data();
> >  	/*
> >  	 * \todo Get the stride from the buffer instead of computing it naively
> >  	 */
> > diff --git a/src/qcam/viewfinder_gl.h b/src/qcam/viewfinder_gl.h
> > index 3334549e0be4..7cd8ef3316b9 100644
> > --- a/src/qcam/viewfinder_gl.h
> > +++ b/src/qcam/viewfinder_gl.h
> > @@ -39,7 +39,7 @@ public:
> >  	const QList<libcamera::PixelFormat> &nativeFormats() const override;
> >  
> >  	int setFormat(const libcamera::PixelFormat &format, const QSize &size) override;
> > -	void render(libcamera::FrameBuffer *buffer, libcamera::Span<uint8_t> mem) override;
> > +	void render(libcamera::FrameBuffer *buffer, Image *image) override;
> >  	void stop() override;
> >  
> >  	QImage getCurrentImage() override;
> > diff --git a/src/qcam/viewfinder_qt.cpp b/src/qcam/viewfinder_qt.cpp
> > index a0bf99b0b522..fef6d53eef5e 100644
> > --- a/src/qcam/viewfinder_qt.cpp
> > +++ b/src/qcam/viewfinder_qt.cpp
> > @@ -19,6 +19,7 @@
> >  
> >  #include <libcamera/formats.h>
> >  
> > +#include "../cam/image.h"
> >  #include "format_converter.h"
> >  
> >  static const QMap<libcamera::PixelFormat, QImage::Format> nativeFormats
> > @@ -78,15 +79,14 @@ int ViewFinderQt::setFormat(const libcamera::PixelFormat &format,
> >  	return 0;
> >  }
> >  
> > -void ViewFinderQt::render(libcamera::FrameBuffer *buffer,
> > -			  libcamera::Span<uint8_t> mem)
> > +void ViewFinderQt::render(libcamera::FrameBuffer *buffer, Image *image)
> >  {
> >  	if (buffer->planes().size() != 1) {
> >  		qWarning() << "Multi-planar buffers are not supported";
> >  		return;
> >  	}
> >  
> > -	unsigned char *memory = mem.data();
> > +	unsigned char *memory = image->data(0).data();
> >  	size_t size = buffer->metadata().planes()[0].bytesused;
> >  
> >  	{
> > diff --git a/src/qcam/viewfinder_qt.h b/src/qcam/viewfinder_qt.h
> > index 1a569b9cee6e..6b48ef48a7d1 100644
> > --- a/src/qcam/viewfinder_qt.h
> > +++ b/src/qcam/viewfinder_qt.h
> > @@ -32,7 +32,7 @@ public:
> >  	const QList<libcamera::PixelFormat> &nativeFormats() const override;
> >  
> >  	int setFormat(const libcamera::PixelFormat &format, const QSize &size) override;
> > -	void render(libcamera::FrameBuffer *buffer, libcamera::Span<uint8_t> mem) override;
> > +	void render(libcamera::FrameBuffer *buffer, Image *image) override;
> >  	void stop() override;
> >  
> >  	QImage getCurrentImage() override;
> > 

-- 
Regards,

Laurent Pinchart


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