qt-everywhere-src-5.15.1/qtmultimedia/src/plugins/gstreamer/mediacapture/qgstreamercameracontrol.cpp

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#include "qgstreamercameracontrol.h"
#include "qgstreamerimageencode.h"

#include <QtCore/qdebug.h>
#include <QtCore/qfile.h>


QGstreamerCameraControl::QGstreamerCameraControl(QGstreamerCaptureSession *session)
    :QCameraControl(session),
    m_captureMode(QCamera::CaptureStillImage),
    m_session(session),
    m_state(QCamera::UnloadedState),
    m_status(QCamera::UnloadedStatus),
    m_reloadPending(false)

{
    connect(m_session, SIGNAL(stateChanged(QGstreamerCaptureSession::State)),
            this, SLOT(updateStatus()));

    connect(m_session->imageEncodeControl(), SIGNAL(settingsChanged()),
            SLOT(reloadLater()));
    connect(m_session, SIGNAL(viewfinderChanged()),
            SLOT(reloadLater()));
    connect(m_session, SIGNAL(readyChanged(bool)),
            SLOT(reloadLater()));

    m_session->setCaptureMode(QGstreamerCaptureSession::Image);
}

QGstreamerCameraControl::~QGstreamerCameraControl()
{
}

void QGstreamerCameraControl::setCaptureMode(QCamera::CaptureModes mode)
{
    if (m_captureMode == mode || !isCaptureModeSupported(mode))
        return;

    m_captureMode = mode;

    switch (mode) {
    case QCamera::CaptureViewfinder:
    case QCamera::CaptureStillImage:
        m_session->setCaptureMode(QGstreamerCaptureSession::Image);
        break;
    case QCamera::CaptureVideo:
        m_session->setCaptureMode(QGstreamerCaptureSession::AudioAndVideo);
        break;
    case QCamera::CaptureVideo | QCamera::CaptureStillImage:
        m_session->setCaptureMode(QGstreamerCaptureSession::AudioAndVideoAndImage);
        break;
    }

    emit captureModeChanged(mode);
    updateStatus();
    reloadLater();
}

bool QGstreamerCameraControl::isCaptureModeSupported(QCamera::CaptureModes mode) const
{
    //only CaptureStillImage and CaptureVideo bits are allowed
    return (mode & (QCamera::CaptureStillImage | QCamera::CaptureVideo)) == mode;
}

void QGstreamerCameraControl::setState(QCamera::State state)
{
    if (m_state == state)
        return;

    m_state = state;
    switch (state) {
    case QCamera::UnloadedState:
    case QCamera::LoadedState:
        m_session->setState(QGstreamerCaptureSession::StoppedState);
        break;
    case QCamera::ActiveState:
        //postpone changing to Active if the session is nor ready yet
        if (m_session->isReady()) {
            m_session->setState(QGstreamerCaptureSession::PreviewState);
        } else {
#ifdef CAMEABIN_DEBUG
            qDebug() << "Camera session is not ready yet, postpone activating";
#endif
        }
        break;
    default:
        emit error(QCamera::NotSupportedFeatureError, tr("State not supported."));
    }

    updateStatus();
    emit stateChanged(m_state);
}

QCamera::State QGstreamerCameraControl::state() const
{
    return m_state;
}

void QGstreamerCameraControl::updateStatus()
{
    QCamera::Status oldStatus = m_status;

    switch (m_state) {
    case QCamera::UnloadedState:
        m_status = QCamera::UnloadedStatus;
        break;
    case QCamera::LoadedState:
        m_status = QCamera::LoadedStatus;
        break;
    case QCamera::ActiveState:
        if (m_session->state() == QGstreamerCaptureSession::StoppedState)
            m_status = QCamera::StartingStatus;
        else
            m_status = QCamera::ActiveStatus;
        break;
    }

    if (oldStatus != m_status) {
        //qDebug() << "Status changed:" << m_status;
        emit statusChanged(m_status);
    }
}

void QGstreamerCameraControl::reloadLater()
{
    //qDebug() << "reload pipeline requested";
    if (!m_reloadPending && m_state == QCamera::ActiveState) {
        m_reloadPending = true;
        m_session->setState(QGstreamerCaptureSession::StoppedState);
        QMetaObject::invokeMethod(this, "reloadPipeline", Qt::QueuedConnection);
    }
}

void QGstreamerCameraControl::reloadPipeline()
{
    //qDebug() << "reload pipeline";
    if (m_reloadPending) {
        m_reloadPending = false;
        if (m_state == QCamera::ActiveState && m_session->isReady()) {
            m_session->setState(QGstreamerCaptureSession::PreviewState);
        }
    }
}

bool QGstreamerCameraControl::canChangeProperty(PropertyChangeType changeType, QCamera::Status status) const
{
    Q_UNUSED(status);

    switch (changeType) {
    case QCameraControl::CaptureMode:
    case QCameraControl::ImageEncodingSettings:
    case QCameraControl::VideoEncodingSettings:
    case QCameraControl::Viewfinder:
        return true;
    default:
        return false;
    }
}