[gst-devel] what is sync=false?

[Michael Smith]

On Tue, May 18, 2010 at 11:56 AM, Daniel Drake <dsd at laptop.org> wrote:
> Hi,
>
> Google shows many examples of using the xvimagesink element with
> sync=false but I can't find any explanation of what this actually does
> and why someone might want to use it. The GstBaseSink documentation
> only has 1 line on this property and it isn't very enlightening.

It simply means that the sink ignores the timestamps on buffers and
the clock, and just displays the frame as soon as it arrives.

>
> What does it do?
>
> In OLPC's Record activity we use xvimagesink for a live video preview
> of the photograph which is about to be taken, or for a live preview of
> the video that we are currently recording to disk. Given that we're
> only talking about a video preview, we're suspecting that sync=false
> is something that we'd want, assuming that it results in xvimagesink
> being able to display frames at times which are most convenient
> without having to worry about the clock, resulting in less resource
> usage on the system. Is there any truth here?

Synchronisation doesn't intrinsically use any significant amount of resources.

Mike