Object wavelet transform for coding of arbitrarily shaped image segments

Object-based coding is one of the most challenging key features which the ISO/IEC MPEG-4 is trying to standardize. One approach to transform an arbitrary shaped image region is addressed. The proposed approach called object-based wavelet transform (OWT), is simple to implement and is a smooth extension of regular wavelet transform (WT). The OWT consist of two phase processes: one is an extrapolation phase for regular WT and the other is a coefficients handling phase for eliminating redundancy caused by the extrapolation. Due to some experimental results, it is confirmed that the method performs the same as other shape-adaptive approaches with low complexity.