[FFmpeg-user] Decklink timestamp_align, what should it do?

[Bouke]

From the manual:
'timestamp_align
Capture start time alignment in seconds. If set to nonzero, input frames are dropped till the system timestamp aligns with configured value

Ok, when I put -timestamp_align in my command, it  does wait ‘a bit’ before starting capture.
That’s what I’m after, but i have no clue how long it waits. It’s not a ‘wait X seconds’ for sure.

So my question, what is 'the system timestamp’? How do I get it so I can enter the correct value?

thx

Bouke