The lecture is base on 2D and 3D tracking, also known as Match moving. In cinematography, match moving is a cinematic technique that allows the insertion of computer graphics into live-action footage with correct position, scale, orientation, and motion relative to the photographed objects in the shot. The term is used loosely to describe several different methods of extracting camera motion information from a motion picture. Sometimes referred to as motion tracking or camera solving, match moving is related to rotoscoping and photogrammetry.(Tim Dobbert, Sybex, Feb 2005) Match moving is sometimes confused with motion capture, which records the motion of objects, often human actors, rather than the camera.
Match moving has been around since 1985and initially used in one or two points to track. It was first used were in the tracking of missiles-implemented by the US Defence Dept. The earliest VFX was used perhaps in 1985 at the famous NYIT graphics lab
Motion Tracking vs Motion Capture uses the same techniques but they’re not the same. Both is the process of recording the movement of objects or people. It is used in military, entertainment, sports, medical applications, and for validation of computer vision and robotics(Goebl, W.Palmer, C. 2013). In filmmaking and video game development, it refers to recording actions of human actors, and using that information to animate digital character models in 2D or 3D computer animation.
- Motion Capture uses a lot of cameras to get a full 3D track and then captures the motion on a 3D rig.
- Tracking gives a good insight into how mocap can work, and how you can go about attempting it.
Difference between 2D and 3D tracking
3D motion tracking also called “match moving” is used when you need to composite elements into a 3D scene. For example , you shoot some footage, and you want to put something in afterwards, in post production. 2D tracking only looks at x,y translation coordinates, +/- other stuff like rotation, sheer, perspective. But 3D tracking adds z-space (depth) , by tracking objects and re-constructing a 3d scene with 3d coordinates, so everything lives in 3D space, in a 3D model, instead of a 2D layer.
Issues that my occur with tracking
To obtain a good tracking the choice of camera is important, and the scene/composition needs to be clear and bright (lighting) cause shadows will mess with the tracking. Fast movement may cause tracking nightmares in slow cameras and the tracking markers becomes blurred and unreadable.
After watching the lecture I went on and researched more on Visual examples about Match moving, 2D & 3D tracking and Motion tracking & Motion capture. (see below)
Matchmoving Reel 20130710, Star Whoo. Youtube Video. Aug, 11, 2013. https://www.youtube.com/watch?v=eyiG3Q1FvfU
The video shows some basic match moving breakdowns and its absolutely amazing.
2D & 3D Tracking Tutorial Reference
3D Tracking in After Effects, Film Riot. Youtube Video. March 22, 2013. https://www.youtube.com/watch?v=s1ans3H9zqU
Film riot has the best tutorials ever and so I obviously went and searched for 2D & 3D tracking videos and i came across to this one. The Video shows some basic and cool techniques when using tracking with texts with the motion of objects.
Motion Capture & Motion Tracking
How Motion Capture Really Works in Movies (HD), actionzone. Youtube video. Dec 9, 2014. https://www.youtube.com/watch?v=ZnrKKjaVxCA
The 4:17 minute video shows some cool Motion tracking and Motion capture scenes and behind the scenes of movies like The Hobit and Lord of the Rings and even in video games nowadays they’re using real life actors the act out the motions and then they track the motion so they could animate it.