qlinuxmediadevice.h

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// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#ifndef QLINUXMEDIADEVICE_H
#define QLINUXMEDIADEVICE_H
 
#include <linux/v4l2-mediabus.h>
 
#include <QtCore/qglobal.h>
#include <QtCore/QString>
 
QT_BEGIN_NAMESPACE
 
class QSize;
class QRect;
 
class QLinuxMediaDevice
{
public:
    QLinuxMediaDevice(const QString &devicePath);
    ~QLinuxMediaDevice();
 
    QString model();
    QString deviceName();
    bool resetLinks();
    struct media_link *parseLink(const QString &link);
    struct media_pad *parsePad(const QString &pad);
    bool enableLink(struct media_link *link);
    bool disableLink(struct media_link *link);
    struct media_entity *getEntity(const QString &name);
    int openVideoDevice(const QString &name);
 
    class CaptureSubDevice
    {
    public:
        CaptureSubDevice(QLinuxMediaDevice *mediaDevice, const QString &name);
        bool setFormat(const QSize &size, uint32_t pixelFormat = V4L2_PIX_FMT_ABGR32); //TODO: fix to match output device
        bool clearBuffers();
        bool requestBuffer();
        bool queueBuffer(int dmabufFd, const QSize &bufferSize);
        bool dequeueBuffer();
        bool streamOn();
        bool streamOff();
    private:
        int m_subdevFd = -1;
    };
 
    class OutputSubDevice
    {
    public:
        OutputSubDevice(QLinuxMediaDevice *mediaDevice, const QString &name);
        bool setFormat(const QSize &size, uint32_t pixelFormat, uint32_t bytesPerLine);
        bool clearBuffers();
        bool requestBuffer();
        bool queueBuffer(int dmabufFd, uint bytesUsed, uint length);
        bool streamOn();
        bool streamOff();
    private:
        int m_subdevFd = -1;
    };
 
    static int openVideoDevice(media_pad *pad);
 
    static bool setSubdevFormat(struct media_pad *pad, const QSize &size, uint32_t mbusFormat = MEDIA_BUS_FMT_ARGB8888_1X32);
    static bool setSubdevAlpha(int subdevFd, qreal alpha);
 
    static bool setSubdevSelection(struct media_pad *pad, const QRect &geometry, uint target);
    static bool setSubdevCrop(struct media_pad *pad, const QRect &geometry);
    static bool setSubdevCompose(struct media_pad *pad, const QRect &geometry);
 
private:
    static bool streamOn(int subDeviceFd, v4l2_buf_type bufferType);
    static bool streamOff(int subDeviceFd, v4l2_buf_type bufferType);
    struct media_device *m_mediaDevice = nullptr;
    const struct media_device_info *m_info = nullptr;
};
 
QT_END_NAMESPACE
 
#endif // QLINUXMEDIADEVICE_H