first let me say this has been a great weekend finding out that blender has the capablites of doing greenscreen with live film. adding cg to live action footage is a dream come ture for me and many other poeple on this forum.
huge thanks to
weirdhat- for showing it was possible
bob-holcomb- for working on his amazing version of blender with chroma-makea-somthing?
mstram- for uploading the special version of blender for us to test with until bob got his site back up!
huge thanks
Disclaimer
*let me say this before anyone tries to start this tutorial
#1 i never ever wrote a tutorial before, so i dont know the proper words, i use words like ropes, blocks, because…i am simple
#2 this is a place to start, i just learned most of this a few hours ago so probably none of it is correct, BUT, the bottom line is this, i learn how to do it with just a screen shot and no prior knowlege of blender 2.42, so you have a huge advantage of having a step by step tutorial, with flashy picutres and such, so no complaints…mmmmmmkay
#3 finally if you are as excited as i am about learning this stuff, who really cares if its right or uses the correct words, as long as it works right!
LETS ALL PAINT OUR BASEMENTS BRIGHT GREEN AND GET SKIN TIGHT GREEN SUITES BECAUSE ITS GREENSCREEN TIME BABY!
what you will need
#1 you will need bob-holcomb’s special matte version of blender
Latest (VS7.1)Windows build (12 AUG 06-1830 EST)
http://scourage.servebeer.com/art/blender_matte.zip
Latest (32 bit) Linux build (13 AUG 06-1800 EST)
http://scourage.servebeer.com/art/blender_matte.tar.gz
#2 for the first tutorial you will need two images, a image with a green background and a image you want to use in place of your green background. if you dont have one you can download the ones i used. (you can right click and save picture)
green image
background image
Nodes/Greenscreen with blender (2d image)
#1 open bob-holcombs special edition of blender (download at links above0, go to camera view, delete cube
#2 add a plane and size it to fit the camera window, add new material with new texture, select image in drop box of texture edit screen, load your image. (i like to go back and add shadless in material section)
#4 set your image size, turn off raytrace (if you want, it renders faster), click do composite, render a test (just to make sure you have an image).
#5 make a new material with a new texture, and in the texture edit section upload your second image (the background image) (you can use the same plane or create a different plane, just be sure the plane in the camera view renders with the image with the green background, before you move onto the node editor)
#6 go into node editor, click composite nodes, click use nodes, your render layers box will pop up (it should have your greenscreen image), and your composite box will pop up, remove the rope between the two).
#7 click add, input, image (this will be the background). load image your background image.
#8 click add, matte, chroma difference, set tolerance to about middle range, (whatever works best, but be sure to set it otherwise no green will be removed from your background).
#9 use rope thinger, to attach render layers box to chroma difference box, click key and select your color, green that matches your background, the color of the background you want to remove.
#10 click add, matte, color spill, click on green in the color spill box, the color of your screen background you are removing (attach rope from chroma difference top right to color spill block bottom left).
#11 click add, color, “alpha over” ,
#12 attach color spill image to the bottom image space on alpha over, this is your green screen image, attach your background image to the top image space on the alpha over block.
#13 attach your alpha over block top right image space to your composite block
#14 render your image, if all done correct you will have your green screen image with no green, and the rest of the image will be put ontop of your background image!
Nodes/Greenscreen with blender (animaiton with greenscreen)
#1 open bob-holcombs blender edition (download above), go into camera view, remove cube, and add plane to fit camera view.
#2 add new material, add new texture with material, select image in material settings, load avi movie
#3 click movie button, in material settings, set number of frames in movie in materail settings (i usually click the shadless option in the material settings).
#4 render settings, remove ray (this is up to you, it renders faster for me), set size, select avi jpeg, set quality of movie, select output, set frames a second, start end frames, be sure to hit “do composite button!”.
#5 add new material,( can use the same plane, just switch material back to green screen animation in the camera/render view before you go onto the nodes editor), add new texture to the new material, load new movie or 2d image (this will be the background image that shows up after the green is removed).
#6 go into node editor, click composite nodes, click use nodes, remove rope from “render layers” block to “composite” block.
#7 in node editor, click add, matte, chroma difference, attach rope from top right “render layers” block to bottom left “chroma difference” block.
#8 in chroma difference block click key and select color of the background you want to remove.
#9 click add, matte, color spill block, click on green or blue the color of the background you want to remove, attach “chroma difference” block rope to color spill box. (on chroma difference block, be sure to set tolerance, this sets how much green you remove, if you leave it on 0 then NO GREEN WILL BE REMOVED!).
#10 attach rope from composite to color spill box, and render a test, all the green background should be gone with just your image being displayed.
#11 remove the rope from your color spill box, from your compositor box.
#12 click add, input, image, select your second background animation or 2d image, to show in place of your greenscreen.
#13 if using animation, select “enable/disable” animation button, and add amount of frames in animation, and first and start frames
#14 click add, color, alpha over, attach your background image, to the alpha over, top space on bottom left side of alphaover box is for the background,
#15 attach with rope your color spill box, to the bottom image space in the alpha over box, the bottom image space is for your greenscreen animation/image.
#16 attach a rope from the alpha over box image (top right image space) to the image space on your composite box.
#17 go to render settings, select the number of frames to animate (should be the same as the number of frames in your green screen animation, i guess?) select a output location and render! (be sure your enabled the movie reading in your background movie clip, othewise it will not show up).
*this might be a bug i dont know, but when i save the blend file, and open it back up the background animation is gone? and i have add it back, but it seems to save fine when the background is just a 2d image and not an animation.
so there you have it, it is a bit rough around the edges, but i was able to figure all this out from just a screen shot, so i’m hopefull all of you will be able to get with two screen shots and some breif descriptions! good luck to all and to all a good night!
i will also post bob-holcomb’s tutorial as soon as he has it up!
helpful links
weirdhat’s green screen animation
http://youtube.com/watch?v=C8Mkm3QtwgE
deep thoughts green screen tutorial
http://blenderartists.org/forum/showthread.php?t=75758
weirdhats omg thread (helpful screenshots page #2)
http://blenderartists.org/forum/showthread.php?t=75758
bob holcombs rgb node thread (with blender downloads for chormakeingying…i dont freaking know)
http://blenderartists.org/forum/showthread.php?t=72268
