The VideoLAN Forums

Hello,

I'm interested in how VLC plays data. From what I've read in the sources and Wiki my assumption is VLC uses kind of timer/clock or loop with sleep between frames. But what exactly drives playback?

For example, in C files regarding Windows I see call timeBeginPeriod(5) which means setting system timer interval to 5 ms. Can you please explain why? To have a timer to draw frames on each tick if needed? Or to change resolution of sleep during infinite loop which draws frames?

Thanks in advance

Timing is specified by the source media.

Timing is specified by the source media.

Can you please explain this? Let's imagine a simple picture: a video that is a set of images with 24fps. How VLC will show this video? I mean, how VLC respects timing between frames (1/24 s)? It's driven by timer or VLC sends graphics buffers to videocard directly waiting for callbacks from it?

VLC 3.0 currently compare the media time against a media clock whose parameters are generated from the media timing information. When the clock says that the media time associated with a frame has been reached, it renders the frame. So in a sense, it's "like" timers yes, and not tickless or event-driven.

VLC 3.0 currently compare the media time against a media clock whose parameters are generated from the media timing information. When the clock says that the media time associated with a frame has been reached, it renders the frame. So in a sense, it's "like" timers yes, and not tickless or event-driven.

Thank you very much for reply!