Motion Stylization Of3D Animated Characters

With the rapid progress of animation industry, animated characters withexaggerative stylistic motion are expected. The motion capture data which canproduce realistic motion could hardly meet the requirements of stylistic animation.Most of the stylistic animation clips are created by hand, the process is timeconsuming and labor-intensive. Therefore, the animation relies heavily onanimators’ skills. Aiming at this problem, a3D animated character oriented methodis proposed to stylize motion easily. Features are extracted with IndependentComponents Analysis method from preprocessed motion sequence, and afterfeature editing the new motion sequence is mapped to the animated character.The thesis focuses on the following problems:(1) Exploring the Probabilistic Principal Component Analysis based motionsegmentation. Firstly, Principal Component Analysis is used to reducedimensionality and to map the data into a low dimensional space dealing with thehigh dimensions of original motion. Secondly, detecting the average Mahalanobisdistance of frames and analyzing the feature of the curve to find segment frame.The pose similarity is introduced to improve the accuracy. The results areoptimized by comparing the distance of current frame and last segment frame.(2) Proposing a method based on Dynamic Time Warping and Hermite curveinterpolation to normalize the length of motion sequences. The motion isrepresented by quaternion and the similarity of frames is defined on this basis. Aset of aligned frames are found by reasonable reduction of the search space. Forthese frames, the root trajectory is interpolated with Hermite curve while the angleis interpolated with quaternion spherical linear interpolation to complete the work.(3) Implementing the stylization of motion sequence based on feature editing.The preprocessing stages include centralization and whitening which can improvethe efficiency of the following algorithm. After preprocessing, the IndependentComponents Analysis is utilized to extract the features to realize editing operationssuch as tuning, transferring and merging the styles to synthesize new stylizedmotion.