Path: news.mathworks.com!not-for-mail
From: Dave Tarkowski <dave.tarkowski@mathworks.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: DV Image Acquisition
Date: Tue, 19 Feb 2008 09:11:01 -0500
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Sudha wrote:
> Hi ,
> I am using Image Acquistion (trial software) with Matlab 
> to grab 60 frames (2 seconds) of DV video.  My frame 
> trigger is set to default (instantaneous).  I am able to 
> grab 60 frames of video, but it  is not in realtime.  i 
> find that there is a delay of 0.26 seconds between the 
> start of trigger and the first frame grabbed.  Please note 
> that frames are grabbed into memory at the moment. The 
> computer has a core duo processor with 2 GB of memory. Are 
> there any other Mathwork solutions for realtime image 
> acquistion? Any help is greatly appreciated.
> Thanks,
> Sudha.

Sudha,

I'm confused by your use of the phrase "real time".  What you are 
describing sounds like an unacceptable latency, not a lack of real time 
capabilities.  When you call START on an a videoinput object, the 
toolbox must connect to the hardware, configure it, and then wait for a 
valid frame to come in.  Depending on your hardware this can take 
anywhere from a few milliseconds to almost a minute.

 From your description above, I think that using the manual trigger 
option should alleviate your problem.

-Dave Tarkowski