Background removal for SL photos -- tips & tool recs?

I am wondering if anyone has any good tips and tool recommendations (if they're plugins, they need to work in PSP) for taking SL photos against a background that you then remove? I have a habit of changing my website background and colour scheme around quite a bit, so I want to be able to change the backgrounds of any SL photos I put up to match.

Green-screen method.

Build a "photo box". Plain hollow box and color it any color you want (though I'd pick a color not on what you're taking a pic of ^.~).

Then simply us PSP, GIMP or other to remove that color. Replace it with an alpha channel or such (I'm not good at graphics not not exaclty sure of teh best method here, but should be very possible).

~Jessy

In PSP : select the background colour with the magic wand, then in Layer menu choose ´new mask layer´ and `hide selection´ .

Can´t say for other programmes, but I´m pretty sure the stickies at the top of the texturing tips forum have that info in them.

Hope this helps.

That's what I was thinking, but my first attempts did not come out very well in terms of getting the green or blue I tried using removed. Also, if you have any clothing that is semi-transparent, that would still leave that colour, I think.

/me waves, hi Freyja!

In that case, maybe use the snapshot depth thing in SL as an alpha channel (increasing it's contrast to separate the foreground from background more)?

Then if you have a far away background of a darker neutral color to your transparent clothing or hair, it might work on whatever background you choose in the future?

PS: The new GIMP has a wonderful foreground selection tool that I have completely switched to instead of green screen or blue screening, almost no selection cleanup.

Hey, Crystal.

Will try playing around with that option too. May have to try out the GIMP some day, as well.

Thanks.

There are lots of web tutorials and books for how to remove all the background stuff. It just takes a little work.

Using a one color background when you make the picture just makes it easier.

Hopefully this post gets moved to the textures forum area. It's really a texturing tech question.

The "Green Screen" approach is a good suggestion, although green, or blue (used in the analog approach in film editing) are not neccessarily the best background colors to use in SL. A simple white background (fullbright prim) behind the subject does quite well against skin, hair, and clothing with a hard edge (no antialiasing). Capture a high resolution snapshot to disk, then reduce the size (after editing out the solid neutral background) to pull out a smooth and crisp edge. Remember to use a "Nearest Neighbor" type of interpolation when reducing the image. This will preserve the clarity of your entire image.

Transparent textures are a little more tricky. What they require are complimentary background colors (black and white, green and red, cyan and magenta, etc.) to isolate the transparent area. The transparent area can be extracted into a fairly accurate alpha channel by performing a difference calculation between the two different colored backgrounds. I can't launch into a full explanation for PSP because my knowledge is centered around photoshop, but the principles remain the same. The trick is to get your two snapshots perfectly aligned and positioned between background changes. For this, a camera system (like CaliCam) that saves position data between edits and logins comes in very handy.

Flexi-prims, eyes, and other parts of the subject that have random uncontrolable movement present the greatest challenge. My only solution to that issue is a bit of image editing (post production) to clean up the artifacting.

Aside from that, there are plenty of filters out there that deal with masking issues too (Magic Mask, Mask Pro, Primatte, etc.). I have no idea if any of these are compatible with PSP, but my gut feeling is that none are. Photoshop CS3 even has it's own build in masking tools that rival most of the high end 3rd party masking add-ons. Photoshop is pretty much industry standard, and most 3rd party developers support Adobe first because they reach the greatest audience that way. It's not entirely fair for the little guy, but that's the way things are.

Thank you for that very thorough explanation, Namssor. I will make sure to try the suggestions you've made. In particular the one regarding how to handle transparencies.

Regarding plugins, PSP used to run all PS plugins fine until CS2, I believe. A new plugin standard was then introduced, and I believe it was made more costly to license, hence the changes weren't introduced into PSP.

Older plugins work fine, however.

I use "chroma screens" in my studio all the time. I use green, unless I need blue to provide better separation between the background and my subject. A helpful tip ... set the chroma texture to "full bright" .... it makes it a lot easier to pull it out later.

I have a cheap chroma-set that I built ... floor and two walls making a corner. Bright green color, full bright ..... works great. But, make sure to pose first before setting the texture full bright. Without the shadows and seams, you'll get lost in the set.

In addition to the tip about using fullbright for greenscreening:

Turn off foot shadows. (in the Client debug menu go to Rendering->Features->Foot Shadows)

2 pics, one using the color setting, one using depth... good for pics of skins, use one to mask the other in you favorite paint program, trim the transparent edges... speeds up the process some