A New Image Enhancement Algorithm via Wavelet Homomorphic Filtering Transform

Abstract

A new spatial-frequency image enhancement algorithm via wavelet homomorphic filtering transform is proposed to enhance the contrast of an image. The wavelet analysis coefficients are processed using a high-pass filter to amplify the high spatial frequencies and attenuate the low spatial frequencies. So the object features can be emphasized while the undesired contributions within the image due to light source nonuniformity can be reduced. Experimental results show that this new algorithm can gain better performance in enhancing the local contrast of an image while maintaining its global appearance, in contrast to some representative algorithms.

Keywords

• image enhancement
• homomorphic filtering
• wavelet transform