Character animation from 2D pictures and 3D motion data

• Published in: ACM transactions on graphics Vol. 26; no. 1; p. 1
• Main Authors: Hornung, Alexander, Dekkers, Ellen, Kobbelt, Leif
• Format: Journal Article
• Language: English
• Published: New York Association for Computing Machinery 01.01.2007
• Subjects: Computer animation; Movement; Three dimensional imaging
• ISSN: 0730-0301; 1557-7368
• DOI: 10.1145/1189762.1189763

This article presents a new method to animate photos of 2D characters using 3D motion capture data. Given a single image of a person or essentially human-like subject, our method transfers the motion of a 3D skeleton onto the subject's 2D shape in image space, generating the impression of a realistic movement. We present robust solutions to reconstruct a projective camera model and a 3D model pose which matches best to the given 2D image. Depending on the reconstructed view, a 2D shape template is selected which enables the proper handling of occlusions. After fitting the template to the character in the input image, it is deformed as-rigid-as-possible by taking the projected 3D motion data into account. Unlike previous work, our method thereby correctly handles projective shape distortion. It works for images from arbitrary views and requires only a small amount of user interaction. We present animations of a diverse set of human (and nonhuman) characters with different types of motions, such as walking, jumping, or dancing.