Don't think this is solved, uninstalling gst-plugins-vaapi is a workaround at best. Bug: Qt Multimedia GStreamer backend doesn't support HW-accelerated video decoding https://bugreports.qt.io/browse/QTBUG-23761

Thank you for tip..I will check it..

@hariny , @onek24 Since this thread was not resolved; the buffer is not open !!! your are missing two lines of code: buffer->open(QIODevice::ReadOnly); buffer->seek(0);

Hi and welcome to devnet, QtMultimedia uses Apple's Media Foundation for it's OS X backend so the format supported depends on what Media Foundation can support. Can you try the same application using the latest version of Qt ?

Hi, Usually, to play sound effect, the QSoundEffect class is used. Wouldn't that fill your need ?

Hi and welcome to devnet, If you want the internal details you should check QtMultimedia's source code.

I'm not sure what happened with the code, but now it's finally giving me an error signal. The error and error string are QMediaPlayer::FormatError "Failed to load media" The media I'm attempting to load uses the file ending ".mp4". I finally thought of opening the media in Quicktime and, lo and behold, it won't open the file. It appears I'm dealing with a "Not a real operating system" error. EDIT: It appears that what happened was that I was trying to open a 0 byte file. Opening an .mp4 file with actual content still causes the MediaPlayer to get stuck in the LoadingMedia status.

Yes it's clearer. Then you should indeed do the synchronization at the source, it will be cleaner and easier.

This is happening to random videos or same videos for everytime? Perhaps you can try this in a different OS (Windows may be) to see if this is a platform specific issue.

Thanks @jsulm I am assuming that problem is in video drivers, I use fbdev by default (/etc/X11/xorg.conf) The same situation with HTML5 video

@Xicor I have no idea, sorry. Maybe someone else knows that.

Yep, thank you but that is what I've talking about, in release about 40 ms on full HD frame. Better to find a way to get RGB frames, not YUV, but I don't know how that all works exactly.

I have opened the bug ticket https://bugreports.qt.io/browse/QTBUG-50460. Perhaps it is really a bug and will get fixed in the future ;D

@SGaist Will do. Thank you!

hi and welcome Maybe you can try with "Media Player Example" to see if it will load and play file. ? Its available directly in creator under the examples tab. just type video in search. It might be it dont like the format.

I just created an empty project to test some stuff. The following code QAudioDeviceInfo info = QAudioDeviceInfo::defaultInputDevice(); // Empty string as output qDebug() << "Default input device" << info.deviceName(); // 0 as output qDebug() << QAudioDeviceInfo::availableDevices(QAudio::AudioInput).size(); // 0 as output qDebug() << QAudioDeviceInfo::availableDevices(QAudio::AudioOutput).size(); prints an empty string as input device, 0 available devices on WinRT. 'multimedia' is added as Qt module. What could be wrong? A missing plugin (dll not deployed automatically)? Or is WinRT not supported (yet)? Best Wickie