Adaptive wavelet processing techniques for weak feature emphasis and extraction
Thomas J. Brown · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2003
This paper introduces image enhancement techniques specifically intended to support the visualization of weak image features. Two distinct strategies are presented, which are referred to as weak feature emphasis and weak feature extraction, respectively. The first emphasizes weakly visible features while simultaneously de-emphasizing stronger features. The second goes further and seeks to extract weakly visible features completely. Both techniques seek to avoid the amplification of noise. The techniques are based on a wavelet foveation strategy which amplifies low magnitude wavelet coefficients and either attenuates or completely removes higher magnitude wavelet coefficients. Fundamental changes in the visible appearance of images can be achieved with these methods.