Application of Homomorphic Filtering to Satellite Imagery and Geophysical Image Data

Homomorphic filtering improves image by enhancing high components and reducing low components in the frequency domain based on FFT, as one of useful digital image processing techniques. In this study, the application program for homomorphic filtering was developed. Using this program, satellite imageries and geophysical image such as magnetic image data were processed and their results were analyzed. In case of applying to other techniques such as histogram equalization and kernel-based masking for the same purpose, they often cause the slight distortion of boundary or overall change of brightness values on the whole image. Whereas, homomorphic filtering has ability to enhance selectively detailed components in a target image. Therefore, this technique can be effectively used for extraction or separation of complex types of characteristics contained in the satellite imagery. In addition, this technique would be applicable to investigate anomalous zone in various geophysical image data.