I can't find any documentation on how a queue works, exactly... It takes a sequence of inputs, and outputs a structure. The patch creator blurb says this is a FILO queue (which makes it more of a stack than a queue?).
Since no popping happens, it's not really a stack nor a queue -- it's more like a fixed-length circular buffer (though queue-like, in that index 0 is always the most recent item added).
First question: when I access items from the structure at different depths (indexes), am I popping off all of the items that I access, or just the most recent? If difference the first and second members of the structure, have I reduced the queue length by 1 or 2?
See above; you never shrink the queue (except when you toggle the reset input) -- items just fall off the end. There's no popping/ pulling/pushing like in a stack, because it's not a stack. It works something like this: An item gets added at index 0, pushing all items back one space. If the last item is beyond the number of entries in the queue (10 by default), it is removed. It's that easy.
Second question: is there a FIFO available, as opposed to the FILO queue? I'm not finding one...
FIFO is possible with the queue -- simply use the structure count patch to find out how many items there are, and then a structure member index patch to extract that item.
Third question: aside from just wanting to know how these patches work, I'm looking for away of comparing time separated frames from a video input. In the simplest case, I'd like to be able to subtract a video frame from the preceding frame (or a the frame that occurred 5 frames earlier).
you'd use a queue for this, and a core image filter that renders the difference between two input frames. There's a built in patch or two that does this already (not sure if they're private or not, but I'm almost certain there's at least one public patch that does exactly this...)
... And Alex beat me to the punch ... :) -- [ christopher wright ] [EMAIL PROTECTED] http://kineme.net/
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