converter.h

Go to the documentation of this file.

/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2020, Laurent Pinchart
 * Copyright 2022 NXP
 *
 * Generic format converter interface
 */

#pragma once

#include <functional>
#include <initializer_list>
#include <map>
#include <memory>
#include <string>
#include <tuple>
#include <vector>

#include <libcamera/base/class.h>
#include <libcamera/base/signal.h>

#include <libcamera/geometry.h>

namespace libcamera {

class FrameBuffer;
class MediaDevice;
class PixelFormat;
class Stream;
struct StreamConfiguration;

class Converter
{
public:
    Converter(MediaDevice *media);
    virtual ~Converter();

    virtual int loadConfiguration(const std::string &filename) = 0;

    virtual bool isValid() const = 0;

    virtual std::vector<PixelFormat> formats(PixelFormat input) = 0;
    virtual SizeRange sizes(const Size &input) = 0;

    virtual std::tuple<unsigned int, unsigned int>
    strideAndFrameSize(const PixelFormat &pixelFormat, const Size &size) = 0;

    virtual int configure(const StreamConfiguration &inputCfg,
                  const std::vector<std::reference_wrapper<StreamConfiguration>> &outputCfgs) = 0;
    virtual int exportBuffers(const Stream *stream, unsigned int count,
                  std::vector<std::unique_ptr<FrameBuffer>> *buffers) = 0;

    virtual int start() = 0;
    virtual void stop() = 0;

    virtual int queueBuffers(FrameBuffer *input,
                 const std::map<const Stream *, FrameBuffer *> &outputs) = 0;

    Signal<FrameBuffer *> inputBufferReady;
    Signal<FrameBuffer *> outputBufferReady;

    const std::string &deviceNode() const { return deviceNode_; }

private:
    std::string deviceNode_;
};

class ConverterFactoryBase
{
public:
    ConverterFactoryBase(const std::string name, std::initializer_list<std::string> compatibles);
    virtual ~ConverterFactoryBase() = default;

    const std::vector<std::string> &compatibles() const { return compatibles_; }

    static std::unique_ptr<Converter> create(MediaDevice *media);
    static std::vector<ConverterFactoryBase *> &factories();
    static std::vector<std::string> names();

private:
    LIBCAMERA_DISABLE_COPY_AND_MOVE(ConverterFactoryBase)

    static void registerType(ConverterFactoryBase *factory);

    virtual std::unique_ptr<Converter> createInstance(MediaDevice *media) const = 0;

    std::string name_;
    std::vector<std::string> compatibles_;
};

template<typename _Converter>
class ConverterFactory : public ConverterFactoryBase
{
public:
    ConverterFactory(const char *name, std::initializer_list<std::string> compatibles)
        : ConverterFactoryBase(name, compatibles)
    {
    }

    std::unique_ptr<Converter> createInstance(MediaDevice *media) const override
    {
        return std::make_unique<_Converter>(media);
    }
};

#define REGISTER_CONVERTER(name, converter, compatibles) \
    static ConverterFactory<converter> global_##converter##Factory(name, compatibles);

} /* namespace libcamera */