[AG-TECH] VIC problems at 25fps

Christoph Willing chris at vislab.usyd.edu.au
Sun Mar 14 19:15:53 CST 2004


On Fri, 2004-03-12 at 21:54, Steven wrote:
>  
> 
> Hello I have noticed a problem with vic on our machines here in the
> UK. The problem is manifested in two ways.
> 
>      1. The GUI for the vic window on the video machine is
>         unresponsive, i.e. it is difficult to access GUI buttons, etc
>         and the window often doesn’t redraw correctly.
[snip]
> 
> A quick fix is to set the 4 transmissions to 24 fps, but I wonder if
> anyone else is suffering from the same problems or has any insights.
> 
> This obviously will only affect those using PAL sources, though it may
> be interesting for someone with an NTSC or indeed SECAM source to
> comment when running at 25fps.
> 

We've seen this here too for a long time. Our quick fix has also been to
restrict the frame rate to 24fps (PAL input).

Given the differing number of pixels in PAL & NTSC frames (therefore the
bandwidth for a particular frame rate), the corresponding test on NTSC
systems is whether they can do 30fps (not 25fps, as suggested above).
Looking at the ANL Lobby right now, all video streams (I presume NTSC
sources) are running at 25fps, not 30fps. NTSC capture at 25fps would be
roughly equivalent to PAL capture at 20fps.


chris



-- 
Chris Willing                      Telephone   (61-2) 9351 3914
Sydney Vislab, F09                      Fax    (61-2) 9351 5955 
University of Sydney
NSW 2006 Australia                http://www.vislab.usyd.edu.au




More information about the ag-tech mailing list