QT video playback in Linux

[Daniel Nilsson]

Hi, I am trying to get QT video playback, preferrably through HW-offload and GL rendering on Ubuntu 16.04. The long-term goal is then to get this also running under Yocto on the i.mx6 platform.

I am trying using Qt 5.7 on my Linux host, but will need to run under QT 5.5 on the i.mx6 target.

My code is as follows:

main.cc:

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QCommandLineParser>
#include <QCommandLineOption>
#include <QtQml>
#include <QtGui>


#define PROJECT_NAME "simpleVideoPlayer"
#define PROJECT_VERSION "0.1.0"

int main(int argc, char *argv[])
{
    int q = 1;

    QGuiApplication app(argc, argv);

    // Print application banner.
    qDebug();
    qDebug() << "Starting" << PROJECT_NAME << " version " << PROJECT_VERSION
             << " - using Qt library " << qVersion();

    QCommandLineParser parser;
    parser.setApplicationDescription("qtsignage");
    QGuiApplication::setApplicationVersion(PROJECT_VERSION);

    parser.addHelpOption();
    parser.addVersionOption();

    QCommandLineOption fileNameOption(QStringList() << "filename",
                QCoreApplication::translate("main", "Video to play"), "videoname");
    parser.addOption(fileNameOption);

    QCommandLineOption videoSinkOption(QStringList() << "videosink",
                QCoreApplication::translate("main", "Force to use this video sink"), "videosink");
    parser.addOption(videoSinkOption);

    parser.process(app);

    // Set GST_ properties
    QString videoSinkString = parser.value(videoSinkOption);
    if (!videoSinkString.isEmpty())
    {
        qDebug() << "Setting videosink to " << videoSinkString;
        qputenv("QT_GSTREAMER_WINDOW_VIDEOSINK", videoSinkString.toUtf8());
    }

    QString fileNameString = parser.value(fileNameOption);
    if (fileNameString.isEmpty())
    {
        qWarning() << "Mandatory video name not set, exit!";
        exit(1);
    }

    QQmlApplicationEngine engine;
    engine.rootContext()->setContextProperty("fileName", fileNameString);
    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
    return app.exec();
}

main.qml:

import QtQuick 2.5
import QtQuick.Window 2.2
import QtMultimedia 5.6

Window {
//Rectangle {
    visible: true
    width:  Screen.width
    height: Screen.height
    color: "red"

    Video
    {
        id: mplayer
        autoPlay: true
        anchors.fill: parent
//        source: "file://" + fileName
        source: "/home/greta/simpleVideoPlayer/20161114_123724.mp4"
    }
}

.pro:

TEMPLATE = app

QT += qml quick multimedia multimediawidgets widgets gui core
CONFIG += c++11 qml_debug

SOURCES += main.cc

RESOURCES += qml.qrc

INCLUDEPATH = "/usr/include/x86_64-linux-gnu/qt5/QtQml/"

# Additional import path used to resolve QML modules in Qt Creator's code model
QML_IMPORT_PATH =

# Default rules for deployment.
include(deployment.pri)

My result is that I get a red fullscreen window that doesnt play anything. Playing video, recording from camera, HW-offload all work on the command line using gstreamer directly.

I am lost as what to do from here. Any suggestions appreciated.

/Daniel