Slitscanner (Composition by psonice)

Author: psonice
License: (unknown)
Date: 2010.01.28
Compatibility: 10.5, 10.6
Categories:
Required plugins:
(none)

Bored at lunchtime, made a slitscanner. It's a simple one, just does a basic static scan, either horizontally or vertically.

PreviewAttachmentSize
new slitscan.qtz18.29 KB

toneburst's picture
Re: Slitscanner (Composition by psonice)

Have you tried the Slitscan iPhone app? It's called 'Timetracks'. Just downloaded it.

a|x

psonice's picture
Re: Slitscanner (Composition by psonice)

Nope, it looks pretty cool though. How well does it work?

gtoledo3's picture
Re: Slitscanner (Composition by psonice)

I'm not sure that this one does work in 10.5... usually, that feedback CI filter command doesn't work. I think that's the case here too -on my screen, I see black, and a small moving strip, not the classic slitscan effect.

usefuldesign.au's picture
Re: Slitscanner (Composition by psonice)

Me too on 10.5 very slow. Prob take 5-10 minutes to fill across from left side to right side. Not classic but nice. Still looking at the CI code to see if I can work it out and speed it up ;).

psonice's picture
Re: Slitscanner (Composition by psonice)

Sorry about 10.5 if it doesn't work.. unfortunately i'm without a 10.5 box these days to test, but I figured that I hadn't used anything 10.6 specific so it should work.

There's definitely plenty of room for improvement, it was done during lunch break so the emphasis was on 'works' rather than 'works well' ;)

All the filter does is shift the sample coordinates 1px to the right (or down), sample from the feedback (so it constantly scrolls) and replace the first row/column with with a row from the camera.

offonoll's picture
Re: Slitscanner (Composition by psonice)

true! it isn't working cuz you plug a lfo with a math punction to a X Horiz and Y Vert. Guys just unplug those and make sure its 0.

But also make sence to choose a portion of image we want, thats donde inside CI, guessing. I tweak the code a bit ;P

here we go! :D

PreviewAttachmentSize
new_slitscan v.1.qtz18.57 KB

psonice's picture
Re: Slitscanner (Composition by psonice)

The LFO's job is to pass the 'slit' across the camera (so it will record say the room the camera is pointing at like a normal camera, but anything moving will look rubbery ;) You can disable it, but it will just be a fixed slit. The math expression patch is just there to round the numbers (the crop patch probably does it anyway, but sub-pixel sampling will blur the effect..)

The slit position isn't set in the CI filter at all - there's a crop patch that takes a 1px wide slice and feeds it into the filter. The LFO is driving that crop patch.

Dropping the LFO shouldn't fix it, but it did cause some strange issues for me. On horizontal mode, the LFO should move the crop from 0..639 (to pan across the image - rendering is hard coded to 640x480). But if I set it to that, I got a weird bug - it works fine, then when the LFO passes a certain level it seems to crop at 1x479 (maybe less) instead of 1x480, so the output image suddenly shrinks..

Well, I didn't figure out what caused it. I don't understand why it should happen at all. It's just weird. Any clues? :)

gtoledo3's picture
Re: Slitscanner (Composition by psonice)

Core Image is a strange mistress.

cybero's picture
Re: Slitscanner (Composition by psonice)

Well psonice, all considered that you just did this as a lunchtime item , it works really nicely & leisurely on 10.6.2, and the second version provides a totally different result, which I'm given to understand is 10.5 compatible, will take another look at that when I get a chance to boot into Leo, but that 2nd version also produces an interesting result.

Must give these a try with some RII based setups.

Cheers.

dust's picture
Re: Slitscanner (Composition by psonice)

i gave it try mr wood on 10.6.1. seems to be a black screen for me but great frame rate. i will let it run in the background see if anything shows up.

Quote:
it works really nicely & leisurely on 10.6.2

cybero 10.6.2 works for you. i can not get qc to open at all in 10.6.2 but one of my friends with an older macbook runs it no problem. has there been any resolution in solving those update issues ?

cybero's picture
Re: Slitscanner (Composition by psonice)

To be honest, I don't really know. I think it's pretty hardware specific and probably also associated with clean or upgrade install profile and , well , still no update on 10.6.3 being released and from what is 'rumoured' it would seem no bad thing.

Doesn't seem right though that machines that were all mutually capable up to their individual pertaining hardware limits with 10.5 should be split apart into a 10.6.x hardware specific heterogeny .

I find that 10.6.2 works on my Mac AOK for the most part.

Others fare better with 10.6.1 or 10.6 or even fare better with 10.5.x - so it goes, the difference is that this is the best level I can work at and others aren't even being given a reasonable choice in the matter, for what we speak of as QC differences is just an echo to other disparities experienced elsewhere as is evidenced within the Apple Support pages.