[PATCH v2 02/12] libcamera: lc-compliance: Add TimeSheet class

[Barnabás Pőcze]

Hi


2024. március 13., szerda 13:12 keltezéssel, Stefan Klug <stefan.klug at ideasonboard.com> írta:

> This class allows us to prepare a time sheet with controls for the frames
> to capture (a bit like the capture script in cam).
> 
> During capture the metadata is recorded. Additionally a mean brightness
> value of a 20x20 pixel spot in the middle of the frame is calculated.
> 
> This allows easy analysis after running the capture without complicated state
> handling due to the asynchronous nature of the capturing process.
> 
> Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>
> ---
>  src/apps/lc-compliance/meson.build    |   1 +
>  src/apps/lc-compliance/time_sheet.cpp | 145 ++++++++++++++++++++++++++
>  src/apps/lc-compliance/time_sheet.h   |  55 ++++++++++
>  3 files changed, 201 insertions(+)
>  create mode 100644 src/apps/lc-compliance/time_sheet.cpp
>  create mode 100644 src/apps/lc-compliance/time_sheet.h
> 
> diff --git a/src/apps/lc-compliance/meson.build b/src/apps/lc-compliance/meson.build
> index c792f072..eb7b2d71 100644
> --- a/src/apps/lc-compliance/meson.build
> +++ b/src/apps/lc-compliance/meson.build
> @@ -16,6 +16,7 @@ lc_compliance_sources = files([
>      'environment.cpp',
>      'main.cpp',
>      'simple_capture.cpp',
> +    'time_sheet.cpp',
>  ])
> 
>  lc_compliance  = executable('lc-compliance', lc_compliance_sources,
> diff --git a/src/apps/lc-compliance/time_sheet.cpp b/src/apps/lc-compliance/time_sheet.cpp
> new file mode 100644
> index 00000000..0ac544d6
> --- /dev/null
> +++ b/src/apps/lc-compliance/time_sheet.cpp
> @@ -0,0 +1,145 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2024, Ideas on Board Oy
> + *
> + * time_sheet.cpp
> + */
> +
> +#include "time_sheet.h"
> +
> +#include <sstream>
> +#include <libcamera/libcamera.h>
> +
> +#include "libcamera/internal/formats.h"
> +#include "libcamera/internal/mapped_framebuffer.h"
> +
> +using namespace libcamera;
> +
> +double calcPixelMeanNV12(const uint8_t *data)
> +{
> +	return (double)*data;
> +}
> +
> +double calcPixelMeanRAW10(const uint8_t *data)
> +{
> +	return (double)*((const uint16_t *)data);
> +}
> +
> +double calculateMeanBrightnessFromCenterSpot(libcamera::Request *request)
> +{
> +	const Request::BufferMap &buffers = request->buffers();
> +	for (const auto &[stream, buffer] : buffers) {
> +		MappedFrameBuffer in(buffer, MappedFrameBuffer::MapFlag::Read);
> +		if (in.isValid()) {
> +			auto data = in.planes()[0].data();
> +			auto streamConfig = stream->configuration();
> +			auto formatInfo = PixelFormatInfo::info(streamConfig.pixelFormat);

Use `const auto &` or `auto &&` with `streamConfig` and `formatInfo` to avoid copies.


> +
> +			std::function<double(const uint8_t *data)> calcPixelMean;

Just use `double (*calcPixelMean)(const uint8_t *)`, std::function is an overkill here.


> +			int pixelStride;
> +
> +			switch (streamConfig.pixelFormat) {
> +			case formats::NV12:
> +				calcPixelMean = calcPixelMeanNV12;

You could alternatively just say

  calcPixelMean = [](const uint8_t *data) -> double { return *data; };

and similarly below. Then you wouldn't need the named functions.


> +				pixelStride = 1;
> +				break;
> +			case formats::SRGGB10:
> +				calcPixelMean = calcPixelMeanRAW10;
> +				pixelStride = 2;
> +				break;
> +			default:
> +				std::stringstream s;
> +				s << "Unsupported Pixelformat " << formatInfo.name;
> +				throw std::invalid_argument(s.str());
> +			}
> +
> +			double sum = 0;
> +			int w = 20;
> +			int xs = streamConfig.size.width / 2 - w / 2;
> +			int ys = streamConfig.size.height / 2 - w / 2;
> +
> +			for (auto y = ys; y < ys + w; y++) {
> +				auto line = data + y * streamConfig.stride;
> +				for (auto x = xs; x < xs + w; x++) {
> +					sum += calcPixelMean(line + x * pixelStride);
> +				}
> +			}
> +			sum = sum / (w * w);
> +			return sum;
> +		}
> +	}
> +	return 0;
> +}

The above functions should be in an anonymous namespace if they are not
used outside this translation unit.


> +
> +TimeSheetEntry::TimeSheetEntry(const ControlIdMap &idmap)
> +	: controls_(idmap)
> +{
> +}
> +
> +void TimeSheetEntry::handleCompleteRequest(libcamera::Request *request, const TimeSheetEntry *previous)
> +{
> +	metadata_ = request->metadata();
> +
> +	spotBrightness_ = calculateMeanBrightnessFromCenterSpot(request);
> +	if (previous) {
> +		brightnessChange_ = spotBrightness_ / previous->getSpotBrightness();
> +	}
> +	sequence_ = request->sequence();
> +}
> +
> +void TimeSheetEntry::printInfo()
> +{
> +	std::cout << "=== Frame " << sequence_ << std::endl;
> +	if (!controls_.empty()) {
> +		std::cout << "Controls:" << std::endl;
> +		auto idMap = controls_.idMap();
> +		assert(idMap);
> +		for (const auto &[id, value] : controls_) {
> +			std::cout << "  " << idMap->at(id)->name() << " : " << value.toString() << std::endl;
> +		}
> +	}
> +
> +	if (!metadata_.empty()) {
> +		std::cout << "Metadata:" << std::endl;
> +		auto idMap = metadata_.idMap();
> +		assert(idMap);
> +		for (const auto &[id, value] : metadata_) {
> +			std::cout << "  " << idMap->at(id)->name() << " : " << value.toString() << std::endl;
> +		}
> +	}
> +
> +	std::cout << "Calculated Brightness: " << spotBrightness_ << std::endl;
> +}
> +
> +TimeSheetEntry &TimeSheet::get(size_t pos)
> +{
> +	auto &entry = entries_[pos];
> +	if (!entry)
> +		entry = std::make_shared<TimeSheetEntry>(idmap_);
> +	return *entry;
> +}
> +
> +void TimeSheet::prepareForQueue(libcamera::Request *request, uint32_t sequence)
> +{
> +	request->controls() = get(sequence).controls();
> +}
> +
> +void TimeSheet::handleCompleteRequest(libcamera::Request *request)
> +{
> +	uint32_t sequence = request->sequence();
> +	auto &entry = get(sequence);
> +	TimeSheetEntry *previous = nullptr;
> +	if (sequence >= 1) {
> +		previous = entries_[sequence - 1].get();
> +	}
> +
> +	entry.handleCompleteRequest(request, previous);
> +}
> +
> +void TimeSheet::printAllInfos()
> +{
> +	for (auto entry : entries_) {

`const auto &entry` to avoid the copy.


> +		if (entry)
> +			entry->printInfo();
> +	}
> +}
> diff --git a/src/apps/lc-compliance/time_sheet.h b/src/apps/lc-compliance/time_sheet.h
> new file mode 100644
> index 00000000..2bb89ab3
> --- /dev/null
> +++ b/src/apps/lc-compliance/time_sheet.h
> @@ -0,0 +1,55 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2024, Ideas on Board Oy
> + *
> + * time_sheet.h
> + */
> +
> +#pragma once
> +
> +#include <future>
> +#include <vector>
> +
> +#include <libcamera/libcamera.h>
> +
> +class TimeSheetEntry
> +{
> +public:
> +	TimeSheetEntry() = delete;
> +	TimeSheetEntry(const libcamera::ControlIdMap &idmap);
> +	TimeSheetEntry(TimeSheetEntry &&other) noexcept = default;
> +	TimeSheetEntry(const TimeSheetEntry &) = delete;
> +
> +	libcamera::ControlList &controls() { return controls_; };
> +	libcamera::ControlList &metadata() { return metadata_; };
> +	void handleCompleteRequest(libcamera::Request *request, const TimeSheetEntry *previous);
> +	void printInfo();
> +	double getSpotBrightness() const { return spotBrightness_; };
> +	double getBrightnessChange() const { return brightnessChange_; };
> +
> +private:
> +	double spotBrightness_ = 0.0;
> +	double brightnessChange_ = 0.0;
> +	libcamera::ControlList controls_;
> +	libcamera::ControlList metadata_;
> +	uint32_t sequence_ = 0;
> +};
> +
> +class TimeSheet
> +{
> +public:
> +	TimeSheet(int count, const libcamera::ControlIdMap &idmap)
> +		: idmap_(idmap), entries_(count){};

No `;` is needed at the end. I'd probably put the `{ }` in a new line
to make it clear that that is the function body.

> +
> +	void prepareForQueue(libcamera::Request *request, uint32_t sequence);
> +	void handleCompleteRequest(libcamera::Request *request);
> +	void printAllInfos();
> +
> +	TimeSheetEntry &operator[](size_t pos) { return get(pos); };
> +	TimeSheetEntry &get(size_t pos);

Why are get() and operator[] needed when they both do the same thing?


> +	size_t size() const { return entries_.size(); };
> +
> +private:
> +	const libcamera::ControlIdMap &idmap_;
> +	std::vector<std::shared_ptr<TimeSheetEntry>> entries_;

Does this need to be shared_ptr? At first glance it seems to me that
unique_ptr would be enough. 


> +};
> --
> 2.40.1


Regards,
Barnabás Pőcze