[libcamera-devel] [PATCH v4 10/11] libcamera: pipeline: simple: Add simple format converter

Niklas Söderlund niklas.soderlund at ragnatech.se
Tue Apr 21 17:57:05 CEST 2020


Hi Laurent,

Thanks for your work.

On 2020-04-04 03:44:37 +0300, Laurent Pinchart wrote:
> The simple format converter supports V4L2 M2M devices that convert pixel
> formats.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> ---
> Changes since v3:
> 
> - Add a comment to explain format enumeration
> 
> Changes since v2:
> 
> - Rebase on top of V4L2PixelFormat
> ---
>  src/libcamera/pipeline/simple/converter.cpp | 213 ++++++++++++++++++++
>  src/libcamera/pipeline/simple/converter.h   |  60 ++++++
>  src/libcamera/pipeline/simple/meson.build   |   1 +
>  3 files changed, 274 insertions(+)
>  create mode 100644 src/libcamera/pipeline/simple/converter.cpp
>  create mode 100644 src/libcamera/pipeline/simple/converter.h
> 
> diff --git a/src/libcamera/pipeline/simple/converter.cpp b/src/libcamera/pipeline/simple/converter.cpp
> new file mode 100644
> index 000000000000..50e554147c5f
> --- /dev/null
> +++ b/src/libcamera/pipeline/simple/converter.cpp
> @@ -0,0 +1,213 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2020, Laurent Pinchart
> + *
> + * converter.cpp - Format converter for simple pipeline handler
> + */
> +
> +#include "converter.h"
> +
> +#include <algorithm>
> +
> +#include <libcamera/buffer.h>
> +#include <libcamera/geometry.h>
> +#include <libcamera/signal.h>
> +
> +#include "log.h"
> +#include "media_device.h"
> +#include "v4l2_videodevice.h"
> +
> +namespace libcamera {
> +
> +LOG_DECLARE_CATEGORY(SimplePipeline);
> +
> +SimpleConverter::SimpleConverter(MediaDevice *media)
> +	: m2m_(nullptr)
> +{
> +	/*
> +	 * Locate the video node. There's no need to validate the pipeline
> +	 * further, the caller guarantees that this is a V4L2 mem2mem device.
> +	 */
> +	const std::vector<MediaEntity *> &entities = media->entities();
> +	auto it = std::find_if(entities.begin(), entities.end(),
> +			       [](MediaEntity *entity) {
> +				       return entity->function() == MEDIA_ENT_F_IO_V4L;
> +			       });
> +	if (it == entities.end())
> +		return;
> +
> +	m2m_ = new V4L2M2MDevice((*it)->deviceNode());
> +
> +	m2m_->output()->bufferReady.connect(this, &SimpleConverter::outputBufferReady);
> +	m2m_->capture()->bufferReady.connect(this, &SimpleConverter::captureBufferReady);
> +}
> +
> +SimpleConverter::~SimpleConverter()
> +{
> +	delete m2m_;
> +}
> +
> +int SimpleConverter::open()
> +{
> +	if (!m2m_)
> +		return -ENODEV;
> +
> +	return m2m_->open();
> +}
> +
> +void SimpleConverter::close()
> +{
> +	if (m2m_)
> +		m2m_->close();
> +}
> +
> +std::vector<PixelFormat> SimpleConverter::formats(PixelFormat input)
> +{
> +	if (!m2m_)
> +		return {};
> +
> +	/*
> +	 * Set the format on the input side (V4L2 output) of the converter to
> +	 * enumerate the conversion capabilities on its output (V4L2 capture).
> +	 */
> +	V4L2DeviceFormat format;
> +	format.fourcc = m2m_->output()->toV4L2PixelFormat(input);
> +	format.size = { 1, 1 };
> +
> +	int ret = m2m_->output()->setFormat(&format);
> +	if (ret < 0) {
> +		LOG(SimplePipeline, Error)
> +			<< "Failed to set format: " << strerror(-ret);
> +		return {};
> +	}
> +
> +	std::vector<PixelFormat> pixelFormats;
> +
> +	for (const auto &format : m2m_->capture()->formats()) {
> +		PixelFormat pixelFormat = m2m_->capture()->toPixelFormat(format.first);
> +		if (pixelFormat)
> +			pixelFormats.push_back(pixelFormat);
> +	}
> +
> +	return pixelFormats;
> +}
> +
> +int SimpleConverter::configure(PixelFormat inputFormat,
> +			       PixelFormat outputFormat, const Size &size)
> +{
> +	V4L2DeviceFormat format;
> +	int ret;
> +
> +	V4L2PixelFormat videoFormat = m2m_->output()->toV4L2PixelFormat(inputFormat);
> +	format.fourcc = videoFormat;
> +	format.size = size;
> +
> +	ret = m2m_->output()->setFormat(&format);
> +	if (ret < 0) {
> +		LOG(SimplePipeline, Error)
> +			<< "Failed to set input format: " << strerror(-ret);
> +		return ret;
> +	}
> +
> +	if (format.fourcc != videoFormat || format.size != size) {
> +		LOG(SimplePipeline, Error)
> +			<< "Input format not supported";
> +		return -EINVAL;
> +	}
> +
> +	videoFormat = m2m_->capture()->toV4L2PixelFormat(outputFormat);
> +	format.fourcc = videoFormat;

I wound set format.size here as well even if it's not strictly needed as 
it adds to readability. With or without this fixed tho,

Reviewed-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>

> +
> +	ret = m2m_->capture()->setFormat(&format);
> +	if (ret < 0) {
> +		LOG(SimplePipeline, Error)
> +			<< "Failed to set output format: " << strerror(-ret);
> +		return ret;
> +	}
> +
> +	if (format.fourcc != videoFormat || format.size != size) {
> +		LOG(SimplePipeline, Error)
> +			<< "Output format not supported";
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +int SimpleConverter::exportBuffers(unsigned int count,
> +				   std::vector<std::unique_ptr<FrameBuffer>> *buffers)
> +{
> +	return m2m_->capture()->exportBuffers(count, buffers);
> +}
> +
> +int SimpleConverter::start(unsigned int count)
> +{
> +	int ret = m2m_->output()->importBuffers(count);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = m2m_->capture()->importBuffers(count);
> +	if (ret < 0) {
> +		stop();
> +		return ret;
> +	}
> +
> +	ret = m2m_->output()->streamOn();
> +	if (ret < 0) {
> +		stop();
> +		return ret;
> +	}
> +
> +	ret = m2m_->capture()->streamOn();
> +	if (ret < 0) {
> +		stop();
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +void SimpleConverter::stop()
> +{
> +	m2m_->capture()->streamOff();
> +	m2m_->output()->streamOff();
> +	m2m_->capture()->releaseBuffers();
> +	m2m_->output()->releaseBuffers();
> +}
> +
> +int SimpleConverter::queueBuffers(FrameBuffer *input, FrameBuffer *output)
> +{
> +	int ret = m2m_->output()->queueBuffer(input);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = m2m_->capture()->queueBuffer(output);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +void SimpleConverter::captureBufferReady(FrameBuffer *buffer)
> +{
> +	if (!outputDoneQueue_.empty()) {
> +		FrameBuffer *other = outputDoneQueue_.front();
> +		outputDoneQueue_.pop();
> +		bufferReady.emit(other, buffer);
> +	} else {
> +		captureDoneQueue_.push(buffer);
> +	}
> +}
> +
> +void SimpleConverter::outputBufferReady(FrameBuffer *buffer)
> +{
> +	if (!captureDoneQueue_.empty()) {
> +		FrameBuffer *other = captureDoneQueue_.front();
> +		captureDoneQueue_.pop();
> +		bufferReady.emit(buffer, other);
> +	} else {
> +		outputDoneQueue_.push(buffer);
> +	}
> +}
> +
> +} /* namespace libcamera */
> diff --git a/src/libcamera/pipeline/simple/converter.h b/src/libcamera/pipeline/simple/converter.h
> new file mode 100644
> index 000000000000..a33071fa8578
> --- /dev/null
> +++ b/src/libcamera/pipeline/simple/converter.h
> @@ -0,0 +1,60 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2020, Laurent Pinchart
> + *
> + * converter.h - Format converter for simple pipeline handler
> + */
> +
> +#ifndef __LIBCAMERA_PIPELINE_SIMPLE_CONVERTER_H__
> +#define __LIBCAMERA_PIPELINE_SIMPLE_CONVERTER_H__
> +
> +#include <memory>
> +#include <queue>
> +#include <vector>
> +
> +#include <libcamera/pixelformats.h>
> +#include <libcamera/signal.h>
> +
> +namespace libcamera {
> +
> +class FrameBuffer;
> +class MediaDevice;
> +struct Size;
> +class V4L2M2MDevice;
> +
> +class SimpleConverter
> +{
> +public:
> +	SimpleConverter(MediaDevice *media);
> +	~SimpleConverter();
> +
> +	int open();
> +	void close();
> +
> +	std::vector<PixelFormat> formats(PixelFormat input);
> +
> +	int configure(PixelFormat inputFormat, PixelFormat outputFormat,
> +		      const Size &size);
> +	int exportBuffers(unsigned int count,
> +			  std::vector<std::unique_ptr<FrameBuffer>> *buffers);
> +
> +	int start(unsigned int count);
> +	void stop();
> +
> +	int queueBuffers(FrameBuffer *input, FrameBuffer *output);
> +
> +	Signal<FrameBuffer *, FrameBuffer *> bufferReady;
> +
> +private:
> +	void captureBufferReady(FrameBuffer *buffer);
> +	void outputBufferReady(FrameBuffer *buffer);
> +
> +	V4L2M2MDevice *m2m_;
> +
> +	std::queue<FrameBuffer *> captureDoneQueue_;
> +	std::queue<FrameBuffer *> outputDoneQueue_;
> +};
> +
> +} /* namespace libcamera */
> +
> +#endif /* __LIBCAMERA_PIPELINE_SIMPLE_CONVERTER_H__ */
> diff --git a/src/libcamera/pipeline/simple/meson.build b/src/libcamera/pipeline/simple/meson.build
> index 4945a3e173cf..8372f24e3788 100644
> --- a/src/libcamera/pipeline/simple/meson.build
> +++ b/src/libcamera/pipeline/simple/meson.build
> @@ -1,3 +1,4 @@
>  libcamera_sources += files([
> +    'converter.cpp',
>      'simple.cpp',
>  ])
> -- 
> Regards,
> 
> Laurent Pinchart
> 
> _______________________________________________
> libcamera-devel mailing list
> libcamera-devel at lists.libcamera.org
> https://lists.libcamera.org/listinfo/libcamera-devel

-- 
Regards,
Niklas Söderlund


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