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My First Plug-In



I wrote a couple plug-ins for QC 3.0 (detailed on my QC blog: http://www.samkass.com/blog) . They're not very efficient, and I was wondering if anyone had started hacking around with the official plug-in interface yet. I included the source to my plug-ins for reference.

Performance Issues:
1. The KLT feature tracking library I have assumes a black and white, 8-bits-per-pixel input image with rowBytes = pixelsWide. Is there any way to, instead of copying bytes around to ensure the correct input, simply specify that that's what I need and use the input buffer directly?
2. Is it less expensive, if I need two subsequent "frames" from the input stream, to use an accumulator latch in patches, or to snag-and- buffer two shots within the plug-in? Probably the latter-- if so, how do I know the input image has changed?
3. In my other plug-in, I try to plot the output from the first plug- in. I basically turn the image into bytes, malloc a new image of the same size, copy the old image over, change a few pixels, then output the new image. This is probably extremely sub-optimal. Ideas?
4. Related to 3, Is valloc better even when I'm changing the data?


	--Sam

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