Eective image compression requires a non-expansive discrete wavelet transform (DWT) be

employed consequently, image border extension is a critical issue. Ideally, the image border

extension method should not introduce distortion under compression. It has been shown in

literature that symmetric extension performs better than periodic extension. However, the

non-expansive, symmetric extension using fast Fourier transform and circular convolution

DWT methods require symmetric lters. This precludes orthogonal wavelets for image compression

since they cannot simultaneously possess the desirable properties of orthogonality

and symmetry. Thus, biorthogonal wavelets have been the de facto standard for image compression

applications. The viability of symmetric extension with biorthogonal wavelets is

the primary reason cited for their superior performance.-Eective image compression requires a non-expansive discrete wavelet transform (DWT) be

employed　consequently, image border extension is a critical issue. Ideally, the image border

extension method should not introduce distortion under compression. It has been shown in

literature that symmetric extension performs better than periodic extension. However, the

non-expansive, symmetric extension using fast Fourier transform and circular convolution

DWT methods require symmetric lters. This precludes orthogonal wavelets for image compression

since they cannot simultaneously possess the desirable properties of orthogonality

and symmetry. Thus, biorthogonal wavelets have been the de facto standard for image compression

applications. The viability of symmetric extension with biorthogonal wavelets is

the primary reason cited for their superior performance.