Lots of people use camera tracking to stick a 3D object into a video, but I’ve not yet seen anyone use camera tracking to stick footage into a 3D background. Since I’m in a film class and we want to try some stuff with 3D backgrounds, I’ve been tinkering around with Icarus and Blender to create a CG environment through which a live actor can walk.
Right now I’m still doing basic motion tests. Please note that these tests look like crap, because they are simple tests just to check the motion. Here is my first test. The subject is a friend.
I used Final Cut Pro, Icarus, Blender, and VirtualDub to create this test. Final Cut Pro wasn’t really necessary, as I only used it to capture. You should be able to capture with any video editing software.
Why it’s crappy
I used Final Cut Pro to capture and then brought the footage home to work with. The footage I brought home was not keyed in any way. To key out the green, I used the color key matte feature built into Icarus. I have little experience with keying and I also was in a huge rush when I shot the footage so I didn’t set up the green screen properly for optimal keying (edit: for one thing, I was manually holding the LED ring that illuminates the screen in front of the camera, you can see it in the corners). Hence, plenty of green is visible. As for the footage itself, I captured it as a .MOV in Final Cut Pro, exported it to an AVI with Microsoft DV codec with FCP, brought it home on a CD, converted to raw AVI with Virtualdub, imported into Blender (along with the matte from Icarus), rendered the background in Blender as an AVI-JPEG, reimported the background, and finally rendered again as an AVI-JPEG. With all that converting, I’m surprised the video looks decent. The keying, again, is terrible.
Is there any way to reduce the amount of motion in the IPO curves? Right now, when I import, the motion is so exaggerated that I have to make the scene hundreds of times a comfortable size to match the camera movement correctly. For one of my tests one object got so big it would no longer show up in the view (in orthographic or perspective).
If people want me to, later I can explain the whole process in detail or write a tutorial. I’m not sure how soon I’ll have time. I also need to refine the process first.
Does anyone know an alternative video host? I don’t like releasing all rights to my videos. I’m not going to upload anything worthwile with Putfile.
edit: Second test - this file is a little over 8 megs and takes a while to load. You can clearly see the tape we used to mark the green screen so that Icarus would have something to track. There is a glitch in the camera motion because we didn’t put enough tracking crosses on the screen but most of it is good.