Contour Image Data Compression Using Spline Wavelets

There are many applications where the shape of objects needs to be encoded, such as CAD, 3D modelling, signature encoding [9], as well as region oriented video coding techniques [1], where the shape information is described by a binary mask having the same values for all the pixels inside the shape. The binary mask indicates the region(s) in which the texture of the object needs to be coded [7]. Contours around the shape in binary masks are generally simple closed ones, without intersection and ambiguous contour continuations (see Figure 1). They are defined usually in pixel resolution, consisting of a number of adjacent pixels that are called contour points. They can be represented, eg , by a chain code [8] or approximated with a polynomial function and subsequently entropy coded [9]. In our case the contour image is converted to its parametric representation and coded with spline wavelets.