Thanks, Allan I've tried this but the performance dips down to about 3fps with 60 image strips (ideally I would have as many strips as there are horizontal scanlines in the video!). I think this is down to the overhead of having so many Billboards, although having many Crop patches might also be the culprit. A queue patch with 100's of frames of video runs at a solid 60fps, so I don't think that is the issue.
I was hoping there was some way of rendering these crops directly to a single patch, almost like an Accumulator that worked as a macro object. 'Render In Image' is *almost* what I want, but with that you still need to render to a destination first. Would it be hard to write an 'Iterator Accumulator' patch that accumulated across an iterator, rather then across time like the current one does? (if that makes any sense!) Thanks Oli -----Original Message----- From: Allan Schaffer [mailto:[EMAIL PROTECTED] Sent: 09 November 2007 17:04 To: Oliver Donald Cc: [email protected] Subject: Re: Efficient way to build images from multiple parts On Nov 9, 2007, at 3:08 AM, Oliver Donald wrote: > I've got a video stream that has been split into numerous horizontal > strips, 32 in total. Is there a simple way to combine these strips > back > into a single image? > > Chaining together 'Composite Add' operators into a tree works, but is > computationally expensive, hard to set up, and worst of all it > produces > graphical artifacts. > > I can use multiple billboards, but again this requires quite a lot of > work. > What I really want is a common, shared destination that my 32 Crop > operators can all write to, is this possible? > > Is there a better way altogether? My first stab at this would be to draw multiple billboards (probably within an iterator, and using a math patch to calculate a Y offset for each billboard) and assuming Leopard & QC3.0, put the whole thing in a "render in image" patch to get a single composite image as a result. ie, result = render in image ( iterator ( billboard ( math(iterator index), input source(iterator index) ) ) ) Allan ___________ Allan Schaffer Graphics Evangelist Worldwide Developer Relations _______________________________________________ Do not post admin requests to the list. They will be ignored. Quartzcomposer-dev mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/quartzcomposer-dev/archive%40mail-archive.com This email sent to [EMAIL PROTECTED]
