Dual ridgelet frame constructed using biorthogonal wavelet basis

A new system, called dual ridgelet frame, is introduced. The construction of the dual ridgelet frame starts with a dual frame constructed using a biorthogonal wavelet basis in the Radon domain, and, then, the image of the resulting dual frame under an isometric map from the Radon domain to the L²(R²) spatial domain is a dual frame again, and we call it a dual ridgelet frame. The dual ridgelet frame can be thought of as an extension of the notion of orthonormal ridgelet. It provides a more flexible and effective tool for image analysis and processing applications. The high performance of the dual ridgelet frame for image denoising is demonstrated experimentally.