I have been experimenting with tracking software for the purpose of adding elements such as set extensions to my footage. Despite an exhaustive, (and exhausting), hunt for some simple, standalone application that will track motion and then composite an image into the footage, I have found nothing exists anywhere in the world… except After Effects, which is prohibitively expensive for an amateur.
I’ve learned that all motion tracking applications need to “export tracking data” to a 3D application, before one can add anything to it. One name that has popped up repeatedly is Blender.
So, what I need to know is: is there a tutorial, or can anyone exlain to me in simple terms, just what one does when one “imports tracking data” into Blender, and how does one go about using Blender to composite a flat image into that footage.
Note I said “flat Image”. I have neither the time, skill, or inclination to learn the art of creating realistic three-dimensional objects and adding them to my footage. All I want to do is to add an image to extend my sets, such as mountains in the distance, buildings, hovering vessels etc, all of which will remain fixed when the camera moves, but will not need to exhibit 3D characteristics because of their “distance” from the camera.
Any help, advice, links, hints, tips, or even sympathy will be sincerely welcomed!
I was actually wanting something that I could use for longer than 30 days. In any case, the procedures in AE would no doubt be different than procedures in other tracking applications, so anything I learned there would very likely be useless for any other application.
Can the 3D object that you add to the footage be a Plane? Like, a flat object without thickness, on to which you can paint a texture, that texture being the image of the thing that you want to add to the footage background?
Imagine a scene shot from a fixed position, panning slowly. If that footage is tracked in Voodoo, you can take that into Blender and stick a cube or whatever on to the horizon so that it looks like you originally panned in order to bring that cube into frame…right? Now, what if instead of a cube, you add a flat Plane, standing perpendicular to the horizon in the scene? And what if you applied a picture of a building, tree, tower, whatever, on to the Plane?
Then your camera pan would reveal the building in the distance, wouldn’t it?
The only question is, can you make the Plane “invisible”, but allow the texture to remain visible? Because the texture photograph would have been processed in Photoshop, Gimp, whatever, to have feathered edges and colour correction, the better to blend into the scene, and you wouldn’t want the hard edges of the Plane to be visible, of course.
Yes, that is possible. Take a look through the wiki at materials and textures (you’ll want a shadeless material with a simple flat image texture) - it should be quite straightforward. When you import your tracking data you should be able to match the camera move, so you’ll just need to position your plane correctly and start rendering (don’t forget the motion blur/vector blur). You may want to look into Blender’s compositing features if you want more control over combining the rendered set extension with the original footage.
I’ve not had much luck with camera tracking though, so hopefully someone with more relevant experience will be able to guide you further.
By the way, may I ask what you’ve used for motion tracking? I’m trying Voodoo, but if you know of a better one that’s also free, would you recommend it?
I used Voodoo too, but I could only get any usable tracking data if the camera was on a tripod. I don’t think I spent enough time exploring the options to get it properly set up for a moving camera. I’ve not tried any other tracking packages.
RP, after what I’ve learned here and there, I plan to only track footage that’s been shot on a tripod. I have tried tracking a hand-held shot of a plane landing, and the little crosses stuck pretty well. But I don’t know how it would look in the final film, because I’m still learning Blender.
When it gets right down to it, if you don’t have the gear to do what you want, you either go out and buy it, or you do without. Either way, you can still make a satisfactory movie if you work within the limits of your gear.
