[libcamera-devel] [PATCH 18/20] libcamera: pipeline: simple: Support configuration of multiple streams

Laurent Pinchart laurent.pinchart at ideasonboard.com
Tue Mar 2 11:43:43 CET 2021


Hi Paul,

On Tue, Mar 02, 2021 at 03:30:16PM +0900, paul.elder at ideasonboard.com wrote:
> On Mon, Feb 01, 2021 at 12:47:00AM +0200, Laurent Pinchart wrote:
> > Extend the SimpleCameraConfiguration to support multiple streams, using
> > the multi-stream capability of the SimpleConverter class. Wiring up
> > multi-stream support in the other pipeline handler operations will come
> > in further commits.
> > 
> > To keep the code simple, require all streams to use the converter if any
> > stream needs it. It would be possible to generate one stream without
> > conversion (provided the format and size match what the capture device
> > can generate), and this is left as a future optimization.
> > 
> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > ---
> >  src/libcamera/pipeline/simple/simple.cpp | 174 ++++++++++++++---------
> >  1 file changed, 104 insertions(+), 70 deletions(-)
> > 
> > diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp
> > index c987e1a0d9cb..58e5f0d23139 100644
> > --- a/src/libcamera/pipeline/simple/simple.cpp
> > +++ b/src/libcamera/pipeline/simple/simple.cpp
> > @@ -538,62 +538,94 @@ CameraConfiguration::Status SimpleCameraConfiguration::validate()
> >  	}
> >  
> >  	/* Cap the number of entries to the available streams. */
> > -	if (config_.size() > 1) {
> > -		config_.resize(1);
> > +	if (config_.size() > data_->streams_.size()) {
> > +		config_.resize(data_->streams_.size());
> >  		status = Adjusted;
> >  	}
> >  
> > -	StreamConfiguration &cfg = config_[0];
> > -
> > -	/* Adjust the pixel format. */
> > -	auto it = data_->formats_.find(cfg.pixelFormat);
> > -	if (it == data_->formats_.end())
> > -		it = data_->formats_.begin();
> > -
> > -	PixelFormat pixelFormat = it->first;
> > -	if (cfg.pixelFormat != pixelFormat) {
> > -		LOG(SimplePipeline, Debug) << "Adjusting pixel format";
> > -		cfg.pixelFormat = pixelFormat;
> > -		status = Adjusted;
> > -	}
> > -
> > -	pipeConfig_ = it->second;
> > -	if (!pipeConfig_->outputSizes.contains(cfg.size)) {
> > -		LOG(SimplePipeline, Debug)
> > -			<< "Adjusting size from " << cfg.size.toString()
> > -			<< " to " << pipeConfig_->captureSize.toString();
> > -		cfg.size = pipeConfig_->captureSize;
> > -		status = Adjusted;
> > -	}
> > -
> > -	needConversion_ = cfg.pixelFormat != pipeConfig_->captureFormat
> > -			|| cfg.size != pipeConfig_->captureSize;
> > -
> > -	cfg.bufferCount = 3;
> > -
> > -	/* Set the stride and frameSize. */
> > -	if (!needConversion_) {
> > -		V4L2DeviceFormat format;
> > -		format.fourcc = data_->video_->toV4L2PixelFormat(cfg.pixelFormat);
> > -		format.size = cfg.size;
> > -
> > -		int ret = data_->video_->tryFormat(&format);
> > -		if (ret < 0)
> > -			return Invalid;
> > -
> > -		cfg.stride = format.planes[0].bpl;
> > -		cfg.frameSize = format.planes[0].size;
> > -
> > -		return status;
> > +	/*
> > +	 * Pick a configuration for the pipeline based on the pixel format for
> > +	 * the streams (ordered from highest to lowest priority). Default to
> > +	 * the first pipeline configuration if no streams requests a supported
> > +	 * pixel format.
> > +	 */
> > +	pipeConfig_ = data_->formats_.begin()->second;
> > +
> > +	for (const StreamConfiguration &cfg : config_) {
> > +		auto it = data_->formats_.find(cfg.pixelFormat);
> > +		if (it != data_->formats_.end()) {
> > +			pipeConfig_ = it->second;
> > +			break;
> > +		}
> >  	}
> >  
> > +	/* Adjust the requested streams. */
> >  	SimplePipelineHandler *pipe = static_cast<SimplePipelineHandler *>(data_->pipe_);
> >  	SimpleConverter *converter = pipe->converter();
> >  
> > -	std::tie(cfg.stride, cfg.frameSize) =
> > -		converter->strideAndFrameSize(cfg.pixelFormat, cfg.size);
> > -	if (cfg.stride == 0)
> > -		return Invalid;
> > +	/*
> > +	 * Enable usage of the converter when producing multiple streams, as
> > +	 * the video capture device can't capture to multiple buffers.
> > +	 *
> > +	 * It is possible to produce up to one stream without conversion
> > +	 * (provided the format and size match), at the expense of more complex
> > +	 * buffer handling (including allocation of internal buffers to be used
> > +	 * when a request doesn't contain a buffer for the stream that doesn't
> > +	 * require any conversion, similar to raw capture use cases). This is
> > +	 * left as a future improvement.
> > +	 */
> > +	needConversion_ = config_.size() > 1;
> 
> Don't we also needConversion_ if we have only one stream but the
> format/size doesn't match?

We do, and that's handled below...

> > +
> > +	for (unsigned int i = 0; i < config_.size(); ++i) {
> > +		StreamConfiguration &cfg = config_[i];
> > +
> > +		/* Adjust the pixel format and size. */
> > +		auto it = std::find(pipeConfig_->outputFormats.begin(),
> > +				    pipeConfig_->outputFormats.end(),
> > +				    cfg.pixelFormat);
> > +		if (it == pipeConfig_->outputFormats.end())
> > +			it = pipeConfig_->outputFormats.begin();
> > +
> > +		PixelFormat pixelFormat = *it;
> > +		if (cfg.pixelFormat != pixelFormat) {
> > +			LOG(SimplePipeline, Debug) << "Adjusting pixel format";
> > +			cfg.pixelFormat = pixelFormat;
> > +			status = Adjusted;
> > +		}
> > +
> > +		if (!pipeConfig_->outputSizes.contains(cfg.size)) {
> > +			LOG(SimplePipeline, Debug)
> > +				<< "Adjusting size from " << cfg.size.toString()
> > +				<< " to " << pipeConfig_->captureSize.toString();
> > +			cfg.size = pipeConfig_->captureSize;
> > +			status = Adjusted;
> > +		}
> > +
> > +		if (cfg.pixelFormat != pipeConfig_->captureFormat ||
> > +		    cfg.size != pipeConfig_->captureSize)
> > +			needConversion_ = true;

... here.

> > +
> > +		/* Set the stride, frameSize and bufferCount. */
> > +		if (needConversion_) {
> > +			std::tie(cfg.stride, cfg.frameSize) =
> > +				converter->strideAndFrameSize(cfg.pixelFormat, cfg.size);
> 
> Is this the right parameter order (did I miss a change earlier in this
> series)?

The compiler doesn't complain :-)

The change is in "[PATCH 03/20] libcamera: pipeline: simple: converter:
Group query functions together".

> > +			if (cfg.stride == 0)
> > +				return Invalid;
> > +		} else {
> > +			V4L2DeviceFormat format;
> > +			format.fourcc = data_->video_->toV4L2PixelFormat(cfg.pixelFormat);
> > +			format.size = cfg.size;
> > +
> > +			int ret = data_->video_->tryFormat(&format);
> > +			if (ret < 0)
> > +				return Invalid;
> > +
> > +			cfg.stride = format.planes[0].bpl;
> > +			cfg.frameSize = format.planes[0].size;
> > +		}
> > +
> > +		cfg.bufferCount = 3;
> > +	}
> >  
> >  	return status;
> >  }
> > @@ -628,16 +660,18 @@ CameraConfiguration *SimplePipelineHandler::generateConfiguration(Camera *camera
> >  		       });
> >  
> >  	/*
> > -	 * Create the stream configuration. Take the first entry in the formats
> > +	 * Create the stream configurations. Take the first entry in the formats
> >  	 * map as the default, for lack of a better option.
> >  	 *
> >  	 * \todo Implement a better way to pick the default format
> >  	 */
> > -	StreamConfiguration cfg{ StreamFormats{ formats } };
> > -	cfg.pixelFormat = formats.begin()->first;
> > -	cfg.size = formats.begin()->second[0].max;
> > +	for ([[maybe_unused]] StreamRole role : roles) {
> > +		StreamConfiguration cfg{ StreamFormats{ formats } };
> > +		cfg.pixelFormat = formats.begin()->first;
> > +		cfg.size = formats.begin()->second[0].max;
> >  
> > -	config->addConfiguration(cfg);
> > +		config->addConfiguration(cfg);
> > +	}
> >  
> >  	config->validate();
> >  
> > @@ -650,7 +684,6 @@ int SimplePipelineHandler::configure(Camera *camera, CameraConfiguration *c)
> >  		static_cast<SimpleCameraConfiguration *>(c);
> >  	SimpleCameraData *data = cameraData(camera);
> >  	V4L2VideoDevice *video = data->video_;
> > -	StreamConfiguration &cfg = config->at(0);
> >  	int ret;
> >  
> >  	/*
> > @@ -694,28 +727,29 @@ int SimplePipelineHandler::configure(Camera *camera, CameraConfiguration *c)
> >  		return -EINVAL;
> >  	}
> >  
> > -	/* Configure the converter if required. */
> > +	/* Configure the converter if needed. */
> > +	std::vector<std::reference_wrapper<StreamConfiguration>> outputCfgs;
> >  	data->useConverter_ = config->needConversion();
> > -	if (data->useConverter_) {
> > -		StreamConfiguration inputCfg;
> > -		inputCfg.pixelFormat = pipeConfig->captureFormat;
> > -		inputCfg.size = pipeConfig->captureSize;
> > -		inputCfg.stride = captureFormat.planes[0].bpl;
> > -		inputCfg.bufferCount = kNumInternalBuffers;
> >  
> > -		ret = converter_->configure(inputCfg, { cfg });
> > -		if (ret < 0) {
> > -			LOG(SimplePipeline, Error)
> > -				<< "Unable to configure converter";
> > -			return ret;
> > -		}
> > +	for (unsigned int i = 0; i < config->size(); ++i) {
> > +		StreamConfiguration &cfg = config->at(i);
> >  
> > -		LOG(SimplePipeline, Debug) << "Using format converter";
> > +		cfg.setStream(&data->streams_[i]);
> > +
> > +		if (data->useConverter_)
> > +			outputCfgs.push_back(cfg);
> >  	}
> >  
> > -	cfg.setStream(&data->streams_[0]);
> > +	if (outputCfgs.empty())
> > +		return 0;
> >  
> > -	return 0;
> > +	StreamConfiguration inputCfg;
> > +	inputCfg.pixelFormat = pipeConfig->captureFormat;
> > +	inputCfg.size = pipeConfig->captureSize;
> > +	inputCfg.stride = captureFormat.planes[0].bpl;
> > +	inputCfg.bufferCount = kNumInternalBuffers;
> > +
> > +	return converter_->configure(inputCfg, outputCfgs);
> >  }
> >  
> >  int SimplePipelineHandler::exportFrameBuffers(Camera *camera, Stream *stream,

-- 
Regards,

Laurent Pinchart


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