I understand, processing is made on CPU anyway. The overhead you get is because you duplicate (or redraw) the image before processing it.
I believe you actually get a CVImageBufferRef from QTKit, not a CIImage, which resides in memory (not VRAM, as it comes from a camera anyway). You could get access to pixel data that way: CVPixelBufferLockBaseAddress CVPixelBufferGetBaseAddress CV...Unlock... Avoiding unnecessary copy. This is not tested. Raphael 2008/5/6 Bridger Maxwell <[EMAIL PROTECTED]>: > I think I was unclear on where I was lost. I didn't think that I would be > able to use the OpenTouch blob detection framework, because I couldn't > pass > it a CIImage, and converting the CIImage to an NSBitMapImageRep was too > slow. The only way to pass the image data to the blob detection library > was > through the function: > > void computeBlobs(int *pixels); > > > Therefor I thought that I would have to work with the CIImage only, > perhaps > by making a CIFilter. How would the ObjC wrapper work? Oh, and I think the > Cocoa app which you are seeing with the OpenTouch source is actually the > one > I am working on right now, I have access the the svn. :) > Thank You, > Bridger Maxwell > > On Tue, May 6, 2008 at 3:50 AM, Mike Abdullah <[EMAIL PROTECTED]> > wrote: > > > This seems an awful lot of work to me for little gain. If you check out > > the OpenTouch source, they have an example Cocoa app which really > requires > > very little extra work. I think you'd be far better off writing an ObjC > > wrapper than creating your own entirely separate framework. Paweł would > > quite likely be happy to even incorporate it into the framework. > > > > Mike. > > > > > > On 6 May 2008, at 08:33, Bridger Maxwell wrote: > > > > Hello,I am trying to write a program that will detect bright "blobs" of > > > light in an image and then track those blobs of light. I would be a > > > Cocoa > > > version of OpenTouch at http://code.google.com/p/opentouch/. I am > > > wondering > > > the best way to do this sort of image processing with Cocoa > frameworks. > > > > > > I have a started this app and use QTKit Capture to grab video from the > > > webcam. I get my images through QTCaptureDecompressedVideoOutput as a > > > CIImage. I can apply some filters to the images and display them in a > > > OpenGLView, but I don't know how I should implement the blob tracking. > > > From > > > experience, making an NSBitmapImageRep from the CIImage so I can work > > > with > > > the image data is far too slow, so I can't work with the blob > detection > > > library used in OpenTouch. Is it possible, or recommended, to > implement > > > the > > > blob tracking as a CIFilter? > > > > > > I read through CIColorTracking sample code, which is very close to > what > > > I > > > want to do. However, CIColorTracking simplifies the areas of interest > > > down > > > to one location (where to place the duck). I am having trouble seeing > > > how it > > > could be adapted to track more than one blob of light. Is it possible > to > > > make a CIFilter that would have an output NSArray containing the > points > > > where the blobs were found? I could see how it would be possible to > > > simplify > > > the image down to an alpha mask of the blobs, but don't know how I > would > > > extract the number of blobs and location of each from that image. > Also, > > > getting the size of the blob would be desirable. > > > > > > I have done a lot of reading and don't seem to be getting anywhere. > Some > > > advice on how to proceed would be greatly appreciated. > > > > > > Thank You, > > > Bridger Maxwell > > > _______________________________________________ > > > > > > 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/cocoadev%40mikeabdullah.net > > > > > > This email sent to [EMAIL PROTECTED] > > > > > > > > > _______________________________________________ > > 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/raphael.sebbe%40gmail.com > > This email sent to [EMAIL PROTECTED] >
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