accumulator

Could someone please explain me how to use the "Replacing Rectangle [Origin/Height/Width]" properties of the Accumulator?

A while ago I posted this very specific question which nobody replied to, so I thought it would be best to ask this basic question first.

Hope someone can help me understand the workings of this patch!

Hi there,

I'm having some trouble with combining the Image Crop and Accumulator patches. I think I misunderstand how you can offset the image using the "Replacing Rectangle" values of the Accumulator:

• Let's say I only need to display the horizontal middle portion of the image, so I want to trim the upper and bottom (please see my screenshot if this sounds complex -- it isn't supposed to be ;-)

• Cropping the image works fine.

• BUT when I feed this image into an Accumulator, things go weird: instead of the full trimmed area, the Accumulator seems to hold only the bottom portion of the image with a black area at the bottom. As if it just crops the image again until it fits into the defined size: "Pixels High" / "Replacing Rectangle (Height)", but then from the original top.

In other words, the Accumulator seems to just ignore the specified offset in Y direction, which -- which explains the black area. (again -- please check the screenshot, I think it's way more clear than me trying to write it down)

• Note: I did try changing the numbers with "Replacing Rectangle" (especially Origin Y) from 0 to almost everything and even negative values, but that doesn't seem to make ANY difference. So clearly, I'm missing something.

Could anyone explain me how I should do this?

thx a lot!

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CONTEXT (not really necessary for understanding my issue, but someone might wanna know): what I'm basically trying to do is trim the Input image BEFORE I feed it into any Core Image Filter, to prevent processing more data than I actually need. However, all cropping I do before any Accumulator in my composition (A LOT) is messed up after them. Hence, my whole output becomes F#*@! up.

After hours of trying without luck, I just gave in and made a quick hack around it by cropping all images AFTER processing them – which of course is pretty dumb and highly inefficient, but it works well enough – for now.... kindof. However, I'd still like to understand why this doesn't function like I think it should (probably: what I'm doing wrong).

Hi!

I'm trying to control pixel accumulator values via midi-controller (Akai MPK Mini or Novation Nocturn). I'm using "Counter" for increasing and decreasing the signal, at the moment it can only be done by using Mac keyboard's arrow buttons (left - and right +). Does anyone know how to map those commands to Midi-controllers faders or rotation knobs? I hope someone understands my question :) Thanks in advance!