CS4480: Assignment #2: Adding CG to the Real World

Overview

Do both parts in groups of 3 people, and submit results by 2pm on each deadline.

Deadlines:

Part a: Calibration:

1. Groups check out camera + tripod.

2. Film dynamic calibration pattern (move and twist the pattern along all 3 axes: static camera, dynamic pattern) & a short action scene with pattern in 2 home locations (static camera, static pattern). For example, a home location could be on the ground where you want to composite a CG dinosaur into your scene or taped to the wall where you want composite in a window looking out into space.

3. Continue filming while moving camera around (slow spin, walk, etc.) w/o pattern. NOTE: This footage is solely used for part c of the assignment (match moving).

4. Digitize the footage

5. Extract 12+ interesting frames from calibration into stills (bmp or tif) with numbered filename suffixes (e.g. frame_21.tif)

6. Pull down a copy of the calibration_tool directory for local use

7. Follow tutorial to calibrate internal camera parameters using stills (copy results into a text file)

8. Follow tutorial to calibrate camera extrinsics for image with pattern in home positions; save translation and rotation matrices to same text file, and submit it to /net/dvfx/DVFX/2006/PS2/your_group_number/

9. See PS2a: Camera Calibration Details

Part b: Compositing

This part of the assignment walks you through mapping the results of Part 1 into the camera model for Maya. Your task is to follow the directions, and then augment either your “home” images or a sequence shot from those camera positions with CG elements of your choice. 75% of the task is the technical aspect of mapping the real-world calibration to virtual cameras, and 25% is your creativity and attention to detail in adding the CG elements. Since you have only one week for this part, focus on quality instead of quantity – we’re happy to see one image done really well vs. a long sequence where things float and the lighting is off. Of course, a well done sequence is better still.

Part c: Match-move experimentation

This part is NOT necessary to complete this assignment, and is purely for experimentation purposes. Do this if you’re eager, if you have time, or if you are thinking of having a moving camera in your final project. MayaLive is a newly available plugin for Maya (Window->Plugins->Mayalive), and has its own documentation (available from the help-menu). Its purpose is to allow the “automatic” tracking of features in an image sequence where the camera was moving. This then produces the equivalent of an extrinsic calibration of the real camera, but does so for each frame of the sequence, and without an explicit calibration pattern. The task: insert CG elements into your video (just like Part II), while using footage shot with a moving camera. Give us feedback on what you thought of MayaLive as a tool, and use this to help you decide to use/not use moving cameras in your final project effect.