Wavelet-based image target detection methods

Target detection in a sequence of images is not trivial when this target is small, faint, and obscured. In these cases, the features of both target and background are generally non-separable in the original image. So, the image has to be transformed onto a space in which those features can be separated. The wavelet transform has been shown to be an excellent methodology for mufti-scale image processing which has been widely used in target detection applications. This paper reviews some of the wavelet-based methods used for target detection. Although the paper reviews the most recent target detection methods using wavelet, which are available in open literature, it focuses on illustrating the different ideas of using wavelet coefficients as a tool for target/background separation. Furthermore, this paper has the objective to offer a quick look to the many approaches, to put in light the authors' most recent developments in this field, and to serve as a background for new advances.