Combining wavelet and fractal coding for 3-D video coding

For low bit rates the visual quality of coded image sequences is more important than objective PSNR error measures. Especially at very low bit rates standard transform coding based methods like H.261 and MPEG suffer from annoying blocking artifacts. Wavelet-based coding schemes using overlapping basis functions avoid these blocking artifacts. At sharp edges however, ringing artifacts become visible. Well designed fractal coders are able to preserve sharp edges even at very low bit rates. But due to the block based algorithm of conventional fractal coders blocking artifacts cannot be avoided. In order to combine the advantages of wavelet and fractal coding, we propose a coding scheme that uses a hybrid approximation of “video cubes” in the 3-D wavelet domain. The combination of a 3-D fractal approximation and a direct encoding of the 3-D wavelet coefficients allows to exploit inter and intra redundancy of the video cubes. The use of smooth wavelet basis functions leads to sharper edges without blocking artifacts even at very low bit rates