On 2010-05-28, at 12:02 PM, cocoa-dev-requ...@lists.apple.com wrote:
> i've tried everything -- how do other people get movie posters and/or grab
> movie frames?
With classic QuickTime if there was no poster frame specifically set in the
movie QuickTime would reliably return the first frame. With QuickTimeKit that
is ... inconsistent. Safest to just grab the first frame yourself.
As for capturing frames, here's the I believe currently recommended way to do
it:
NSDictionary *imageAttrs = [NSDictionary dictionaryWithObjectsAndKeys:
QTMovieFrameImageTypeNSImage, QTMovieFrameImageType,
[NSArray arrayWithObject:@"NSBitmapImageRep"],
QTMovieFrameImageRepresentationsType,
[NSNumber numberWithBool:YES], QTMovieFrameImageDeinterlaceFields,
[NSNumber numberWithBool:YES], QTMovieFrameImageHighQuality,
[NSNumber numberWithBool:YES], QTMovieFrameImageSingleField,
nil
];
QTTime captureTime = [0 .. self.movie.duration];
NSError *captureError = nil;
NSImage *captureFullFrame = [self.movie frameImageAtTime:captureTime
withAttributes:imageAttrs
error:&captureError
];
That allows for a variety of other image types besides
QTMovieFrameImageTypeNSImage, but is QuickTime 7.2 dependent. If you need older
version compatibility, use
- (NSImage *)frameImageAtTime:(QTTime)time;
Either way, these should only be called on the main thread. Theoretically you
can detach movies and move them around between threads, but you have a good
chance of running into issues doing so, particularly if you're working with
QTKit captured movies; something about the rendering context I think, although
the details are old enough to be kinda fuzzy now. Safer to just call
performSelectorOnMainThread: to get each grabbed frame if you've got a
background renderer or suchlike, I'd say.
--
Alex Curylo -- a...@alexcurylo.com -- http://www.alexcurylo.com/
"...the variable PI can be given that value [3.141592653589793] with
a DATA statement. This simplifies the modifying of the program,
should the value of PI ever change." -- SDS Sigma series Fortran manual
_______________________________________________
Cocoa-dev mailing list (Cocoa-dev@lists.apple.com)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com
This email sent to arch...@mail-archive.com
