Video lags on STM32MP157DAC custom boad when playing through Qt6 application

[adnan_pasha]

Hi STM Team,

We are working with a custom board based on the STM32MP157DAC.We are facing a video lag issue when trying to play a video file from Qt application 6.5.3 using media player.

Even reducing the frame rate had no effect.

But if we use gst-play we are able to play the video without any lag or delay.

Do we need to enable any HW accelerator to play the video over GPU from Qt application? how we achive the same video output without lag when played using gst-play from Qt application.

Thanks.

[adnan_pasha]

Hello,

I was able to achieve smooth video playback in a Qt application by using a GStreamer pipeline with qml6glsink. By default, qml6glsink is not enabled in gst-plugins-good. After enabling it, I was able to use it successfully. Below is a link to the example code I referenced:

• https://forum.qt.io/topic/151706/qml6glsink

• https://gitlab.freedesktop.org/gstreamer/gstreamer/-/tree/main/subprojects/gst-plugins-good/tests/examples/qt6/qmlsink?ref_type=heads

However, I have observed high CPU usage during video playback with qml6glsink from the Qt application. The CPU usage remains around 130–140%.

Is there a way to reduce CPU usage, possibly by offloading more processing to the GPU?

Thank you.