Again, thanks a lot for all the helpful hints. Before restructuring my code, I did a few timings, using a set of test images ranging in size from 30 through 300 MB. I used mach_absolute_time() for this experiment. And now, I am confused.
These are the execution times I have found for some of the methods that I invoke in the process of loading and displaying the next image: CGImageSourceCreateWithURL: 0.4-1.4 millisec CGImageSourceGetStatus: 10-600 microsec CGImageSourceCopyPropertiesAtIndex: 0.8-9 millisec CGImageSourceCreateImageAtIndex: 15 microsec convertToNSImage (*): 25 microsec imgLayer.contents = nsimage: 1-5 microsec removeFromSuperlayer: 0.1 microsec addSublayer: 5-10 microsec (*): this is a wrapper method of mine that does a few calls to CIImage/NSImage/NSCIImageRep methods. Overall, none of the methods I invoke seems to incur a long execution time. Yet, there is a noticeable lag when my app switches from one image to the next one. I can tell because all layers have an animation assigned. Sometimes , there is even a stutter in the animation itself. But it doesn't seem like it makes sense at this point to load images in a concurrent/background dispatch queue, does it? So, I am confused: where is the lag coming from? Any ideas how I might be able to prevent the lag/stutter when loading and switching to big images? Best, G. _______________________________________________ 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: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
