I have a simple Qt application that launches a window with a QWebView. I tried several sites using the video tag with h.264, and it either can't play the video at all (as in youtube or sublime video), or it renders the video poorly, with black lines covering parts of it, like when viewing the video here.

Is this a known issue with QtWebKit, or have I neglected to do something that would make it work better? My code is below.

#include <QtGui/QApplication>
#include <QWebView>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QWebView *view = new QWebView();
    view->load(QUrl("http://webkit.org/blog/140/html5-media-support/"));
    view->show();

    return a.exec();
}