Flickering video when looping using QGraphicsView

[spmyn]

Hello,

I have a project that needs to display QLabel on top of a video. In order to do so, I figured out that I should use QGraphicsView to display a video.

Here is my code:

player = new QMediaPlayer;
playlist = new QMediaPlaylist(player);
 
item = new QGraphicsVideoItem;
playlist->addMedia(QUrl::fromLocalFile("path/to/video"));
playlist->setCurrentIndex(0);
playlist->setPlaybackMode(playlist->Loop);
player->setPlaylist(playlist);
player->play();
player->setVideoOutput(item);
scene = new QGraphicsScene;
ui->graphicsView->setScene(scene);
ui->graphicsView->scene()->addItem(item);

player = new QMediaPlayer;
playlist = new QMediaPlaylist(player);

item = new QGraphicsVideoItem;
playlist->addMedia(QUrl::fromLocalFile("path/to/video"));
playlist->setCurrentIndex(0);
playlist->setPlaybackMode(playlist->Loop);
player->setPlaylist(playlist);
player->play();
player->setVideoOutput(item);
scene = new QGraphicsScene;
ui->graphicsView->setScene(scene);
ui->graphicsView->scene()->addItem(item);

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Everything works fine. The problem is my video runs in a loop and it flickers every time it starts a new loop.

How can I make it run smoothly?

[d_stranz]

It would help if you gave a little context that shows where this code is being executed. It obviously isn't your real code - line 7, for example, is a syntax error.

[spmyn]

I am using Qt 5.6 MinGW 32bit on Win10 64bit.
I have installed K-Lite Codec and LAVFilters.

That piece of code is in mainwindow.cpp. graphicsView is set in Ui.

I have changed line 7 to

playlist->setPlaybackMode(QMediaPlaylist::Loop);

playlist->setPlaybackMode(QMediaPlaylist::Loop);

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but appears the same issue.

I have also tried setMedia to player instead of addMedia to playlist but video doesn't appear at all.
Now I can show the video using addMedia with playlist and with flickering issue when the loop ends.

I don't know if this relates but I have this error both with setMedia and addMedia:

DirectShowPlayerService::doRender: Unresolved error code 80040200

DirectShowPlayerService::doRender: Unresolved error code 80040200

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However the video shows (if using addMedia)

[d_stranz]

That piece of code is in mainwindow.cpp. graphicsView is set in Ui.

Great. Now where in mainwindow.cpp does that code appear?