Videoplayback performance / optimizations?

[capital4]

We are using the latest version of screensaver factory (enterprise) and try to create a screensaver (scr only) that loops a video file.

The video is a mp4 file with h264 codec, created (transcoded) with FFmpeg. It is about 10mb in size, full hd 1920x1080, and about 2 minutes long.
We want to display it fullscreen (scale proportionally) and loop forever.
We have activated the FFmpeg option in the project settings (so FFmpeg is included into the scr file).

This generally works ... on fast computers.
On slower computers, the video playback is choppy or there are artifacts visible. The CPU usage is stated to be very high by the tech admin who is testing the scr file on some computers.
The very same mp4 video file on the same computers, but played with VLC and Windows Mediaplayer, runs smoothly in fullscreen.
These computers usually have a fullHD display attached (so there is actually no upscaling done) and don't have dedicated GPUs (so it's usually intel graphics only).

Possible solutions?
a) We've read about switching FFmpeg playback from GPU to CPU or the other way around, to try if this works better. But there is no setting for this within screensaver factory, and we can't find a config file for FFmpeg to change either. (also, we are no experts with this, so if there is a way, we'd need some guidance maybe).
b) is there a way to update the FFmpeg library by exchanging files, if this is something that could bring improvements? (the used libaries are from 2013, maybe a newer version of FFmpeg could solve something?)
c) Is there anything else we could try / change / optimize to make the video run more smoothly and with less CPU load?

Thanks for your help
Steve

[Aivars]

Unfortunately there are no settings to tweak this. Maybe another video screensaver with lower resolution could be used for slower computers?

[Dreadonat]

I had a similar problem a while ago when trying to play looped MP4 files on some older office desktops. The playback was also smooth in VLC but would lag in other applications, mostly because certain players use hardware acceleration better. What helped me a bit was converting the video to a different format or profile with a lower bitrate, just enough to keep the visual quality decent while easing up on CPU demand. Reducing frame rate from 30 to 24 fps also made a noticeable difference without hurting playback too much.