TR-IIS-01-006    pdffile

Wavalet-based Active Contour Model for Object Segmentation and Tracking in Video Sequences

 Jen-Chang Liu 1,2, Wen-Liang Hwang 2, Ming-Syan Chen 1, Jin-Wu Tsai 3, and Chi-Hung Lin 3

1 Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan

2 Institute of Information Science, Academia Sinica, Nankang, Taipei, Taiwan

3 Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan

Abstract

We propose an integrated wavelet-based framework of the active contour model (snake) for segmentation and motion tracking of deformable objects in video sequences. The input image frame is represented by means of wavelet transform. First, the moduli of wavelet transform coefficients are used in a multi-resolution motion estimation process to find the initial snake contour in the current frame. The presented multi-resolution motion estimation methods allow a larger movement of the tracked object than does traditional image-based motion estimation. Secondly, the wavelet transform modulus at each scale is considered in the energy function of the snake model. The snake computation is based on a coarse-to-fine scale continuation method. Application of the proposed methods to biological cell tracking is demonstrated in experiments.