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Show HN: Remove backgrounds from images online

clippingmagic.com

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Re: Show HN: Remove backgrounds from images online

#11

Post by jacobn »

stmchn wrote: post #10

Really neat. I was really itching to use CTRL+Z though. I screwed up the first image I tried to clip. Maybe have a walkthrough of the features when the user first uses it? I didnt notice the help button until it was too late. I thought if I closed out of the editor and clicked on the image again, it would let me start over but it just takes you back to the editor. It would be nice if there was a way to redo editing t…

Yeah, we need to add both undo and reset/clear.

The help should have shown during the upload / init!?

Re: Show HN: Remove backgrounds from images online

#12

Post by jacobn »

huhtenberg wrote: post #7

Tried removing a background from a stock car photo. It involved quite a bit of precise mouse wiggling and the end result was still pretty sloppy looking. I assume there are cases where this works well, but it would probably help clarifying what those are before inviting people to try the tool out.

See the bottom of the page (yes, it could be more clear): you need good edges in the image. Ideally also good chromatic separation.

Re: Show HN: Remove backgrounds from images online

#15

Post by Bjoern »

ank286 wrote: post #8

does it use GraphCuts?

Like the interface! :)

There are many ways to solve such a problem. Another one beside GrabCub would be e.g. Watershed.

https://en.wikipedia.org/wiki/GrabCut

http://en.wikipedia.org/wiki/Watershed_%28image_processing%2...

So many variations available via e.g. OpenCV.

Re: Show HN: Remove backgrounds from images online

#16

Post by jacobn »

mnicole wrote: post #9
jacobn wrote: post #5

Earlier quoted context omitted.

Also, one of our usability headaches is that people draw OUTSIDE of the lines - any pixel marked green WILL BE IN THE RESULT. Now, that's not how people actually use it at first - they "just scribble" (which our example might exacerbate), and then accidentally go outside the actual lines => not good. Will need to figure out a way to make that more clear.

I copied the marks in the example and besides needing to tell it to include the cream color under the strap, it worked exactly as shown on the homepage, so maybe just add that extra red there in the example. Unfortunately it is freezing up on me using an image with a gradient at about 90% of the initialization.

Yeah, we're getting some null pointers in the worker. Not entirely clear why that's happening (it of course wasn't happening an hour ago...).

I think I stuck a race condition in there somewhere and it's getting exposed for the first time.

Please try uploading the image again :-/

Re: Show HN: Remove backgrounds from images online

#17

Post by jrd79 »

Bjoern wrote: post #15
ank286 wrote: post #8

does it use GraphCuts?

Like the interface! :) There are many ways to solve such a problem. Another one beside GrabCub would be e.g. Watershed. https://en.wikipedia.org/wiki/GrabCut http://en.wikipedia.org/wiki/Watershed_%28image_processing%2... So many variations available via e.g. OpenCV.

(I'm one of the devs.)

Regarding the segmentation phase, we were not satisfied with any existing algorithms because we wanted the tool to be as real-time as possible (for up to 4 megapixel images), so we rolled our own segmentation algorithm that has some similarities to GrabCuts (not GraphCuts).

But the binary segmentation is really only a small part of the technical challenge. You also need to figure out how to anti-alias the boundary, and remove the background halo. Simply feathering doesn't do the job unless you also erode the foreground first, which we wanted to avoid. So we developed a custom sub-pixel background-removal and anti-aliasing algorithm.

Re: Show HN: Remove backgrounds from images online

#20

Post by jrd79 »

itry wrote: post #18

Pretty Awesome. Would be good if you could choose a smaller brush.

You can get a smaller brush by zooming in using the mouse wheel. That way the brush is always an appropriate size (small when you are zoomed in for detail work, and large when you are zoomed out for the broad strokes).
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