Re: QTMovie grabing while playback

FROM : Bob Smith
DATE : Thu Apr 24 22:14:54 2008

On Apr 23, 2008, at 1:08 PM, douglas a. welton wrote:

> Bob & Randall,
>
> If all you want to do is slap some arbitrary text over a movie, I 
> would suggest that you take a look at using  QTMovieLayer and 
> CATextLayer as the mechanism for doing this.  I don't have any code 
> that I can share with you on this, but a previous client project 
> used these two Core Animation objects with excellent results.
>
> regards,
>
> douglas
>


I will look into that, because my problem isn't solved yet.  I wasn't 
able to get my app working using the Core Video display link because 
QuickTime wouldn't give me new frames when it was playing live 
streaming video.  However using the -view:willDisplayImage: delegate 
callback... doesn't work either, for the same reason!  The delegate 
method works fine for video from a file, but it is _never_called_ 
when QuickTime is playing a live video stream.  Anyone know what is 
going on here?  Is this some sort of DRM nonsense to prevent us from 
capturing live streams?

In my case all I want to do is be able to add a scrolling text 
overlay to whatever video is being played.  My app is an 
informational video kiosk display driver, it's meant to run mostly 
unattended from playlists of images and pre-recorded video, but with 
occasional scheduled live segments from streaming video cameras on 
the local network.  I'll take a look at Core Animation, however one 
of my limitations is the app has to run under Tiger, and I thought 
most of the CA stuff was new to Leopard.

Thanks to all for your help.

Bob