revVideoGrabber: stop preview doesn't hide video window

Martin Koob mkoob at
Sun Aug 8 09:59:45 EDT 2010

Ben Rubinstein <benr_mc at ...> writes:

> Thanks, Stephen and Richard.
> Because I'm selfishly focused on my immediate needs, can you clarify "long 
> grabs" and "problems"?  Are long grabs like Stephen's two hours, or would five 
> minutes qualify?  Are problems sync drift, or crashing, or memory leaks, or... 
> something else?
> My application will probably not be doing more than a few minutes per clip - 
> but it will be doing lots and lots of them over a day. Obviously I'll be 
> testing this for myself - but it would be good to have tips on what to look 
> out for.
> Many thanks,
> Ben

I have a mac application that uses revVideograbber extensively and
the captures range from a few minutes to over an hour.   I have not noticed
sync issues.

I have dealt with the problem of stop preview window by using 
closevideograbber to get rid of the preview window.

One of the things I have noticed is the high CPU use while previewing or 
recording. It is higher than other mac applications that capture video.

The other annoyance is the inability to turn off the audio while previewing.  
Sometimesthat results in audio feedback depending on the placement 
of microphones and the volume setting of the Mac.  
You can use an undocumented keyword for revvideograbdialog 

revVideograbdialog "audio" 

 to see a QT audio dialog to turn off the 
sound while previewing but if you try to save the settings it results in
problems with the video settings.

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