[libcamera-devel] [PATCH 3/3] cam: Add option to exit capture loop after n frames

[Niklas Söderlund]

Hi Andrey and Kieran,

On 2020-07-24 16:58:42 +0300, Andrey Konovalov wrote:
> Hi Niklas,
> 
> This is a very nice addition to cam!
> 
> Just could it be easier to add a numerical argument to the "capture" option ('cam -C <N>' - similar
> to how yavta works) rather creating a new option?

This is a great suggestion pointed out by you and Kieran and I will do 
so for v2.

> 
> Thanks,
> Andrey
> 
> On 24.07.2020 16:43, Niklas Söderlund wrote:
> > Add an option '--count' to specify how many frames to capture before
> > terminating the capture loop.
> > 
> > Signed-off-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
> > ---
> >   src/cam/capture.cpp | 17 +++++++++++++++--
> >   src/cam/capture.h   |  2 ++
> >   src/cam/main.cpp    |  2 ++
> >   src/cam/main.h      |  1 +
> >   4 files changed, 20 insertions(+), 2 deletions(-)
> > 
> > diff --git a/src/cam/capture.cpp b/src/cam/capture.cpp
> > index aa53c407d7b71b44..3ca70d9c6a8c7b7e 100644
> > --- a/src/cam/capture.cpp
> > +++ b/src/cam/capture.cpp
> > @@ -17,7 +17,8 @@
> >   using namespace libcamera;
> >   Capture::Capture(std::shared_ptr<Camera> camera, CameraConfiguration *config)
> > -	: camera_(camera), config_(config), writer_(nullptr), loop_(nullptr)
> > +	: camera_(camera), config_(config), writer_(nullptr), loop_(nullptr),
> > +	  captureCount_(0), captureLimit_(0)
> >   {
> >   }
> > @@ -26,6 +27,8 @@ int Capture::run(EventLoop *loop, const OptionsParser::Options &options)
> >   	int ret;
> >   	loop_ = loop;
> > +	captureCount_ = 0;
> > +	captureLimit_ = options.isSet(OptCount) ? options[OptCount].toInteger() : 0;
> >   	if (!camera_) {
> >   		std::cout << "Can't capture without a camera" << std::endl;
> > @@ -133,7 +136,11 @@ int Capture::capture(FrameBufferAllocator *allocator)
> >   		}
> >   	}
> > -	std::cout << "Capture until user interrupts by SIGINT" << std::endl;
> > +	if (captureLimit_)
> > +		std::cout << "Capture " << captureLimit_ << " frames" << std::endl;
> > +	else
> > +		std::cout << "Capture until user interrupts by SIGINT" << std::endl;
> > +
> >   	ret = loop_->exec();
> >   	if (ret)
> >   		std::cout << "Failed to run capture loop" << std::endl;
> > @@ -202,5 +209,11 @@ void Capture::requestComplete(Request *request)
> >   		request->addBuffer(stream, buffer);
> >   	}
> > +	captureCount_++;
> > +	if (captureLimit_ && captureCount_ >= captureLimit_) {
> > +		loop_->exit(0);
> > +		return;
> > +	}
> > +
> >   	camera_->queueRequest(request);
> >   }
> > diff --git a/src/cam/capture.h b/src/cam/capture.h
> > index 67c6260bfe24aefc..0a1cbc519f2a90c5 100644
> > --- a/src/cam/capture.h
> > +++ b/src/cam/capture.h
> > @@ -40,6 +40,8 @@ private:
> >   	std::chrono::steady_clock::time_point last_;
> >   	EventLoop *loop_;
> > +	unsigned int captureCount_;
> > +	unsigned int captureLimit_;
> >   };
> >   #endif /* __CAM_CAPTURE_H__ */
> > diff --git a/src/cam/main.cpp b/src/cam/main.cpp
> > index a223563ad37e9fe5..f3bacb4a895600ee 100644
> > --- a/src/cam/main.cpp
> > +++ b/src/cam/main.cpp
> > @@ -188,6 +188,8 @@ int CamApp::parseOptions(int argc, char *argv[])
> >   	parser.addOption(OptStrictFormats, OptionNone,
> >   			 "Do not allow requested stream format(s) to be adjusted",
> >   			 "strict-formats");
> > +	parser.addOption(OptCount, OptionInteger, "Number of frames to capture",
> > +			 "count", ArgumentRequired, "count");
> >   	options_ = parser.parse(argc, argv);
> >   	if (!options_.valid())
> > diff --git a/src/cam/main.h b/src/cam/main.h
> > index 6f95add31a6341cf..d4c93fee35681e86 100644
> > --- a/src/cam/main.h
> > +++ b/src/cam/main.h
> > @@ -18,6 +18,7 @@ enum {
> >   	OptStream = 's',
> >   	OptListControls = 256,
> >   	OptStrictFormats = 257,
> > +	OptCount = 258,
> >   };
> >   #endif /* __CAM_MAIN_H__ */
> > 

-- 
Regards,
Niklas Söderlund