// pdfmodel.cpp

int PdfModel::loadProvider()
{
    m_providersNumber = QThread::idealThreadCount();
    qDebug() << "Ideal number of image providers is:" << m_providersNumber;

    qDebug() << "Loading image provider(s)...";
    QQmlEngine *engine = QQmlEngine::contextForObject(this)->engine();

    for (int i=0; i<m_providersNumber; i++)
        engine->addImageProvider(QLatin1String("poppler" + QByteArray::number(i)), new PageImageProvider(document));

    qDebug() << "Image provider(s) loaded successfully !";

    return 1;
}


// PdfViewDelegate.qml

Image {
    id: pageImg
    anchors.fill: parent

    source: "image://poppler" + (index % poppler.providersNumber()) + "/page/" + index;
    sourceSize.width: pdfPage.width
}