Object-based compression (OBC) segments regions from images, then compactly represents region contents and boundaries, thus efficiently approximating source imagery. In practice, OBC tends to exhibit superior compression ratio (CR) when compared with transform coding (e.g., JPEG, JPEG2K, or MPEG) or vector quantization. Object approximation leads to semantic equivalence in decompressed versus source images, producing visually acceptable but numerically significant pixel-level distortion [1,3].