抄録
In this paper, we deal with the lag detection of artificial ghost images based on the cepstral technique in order to apply the ghost images to information hiding(digital watermarking). First we express the phenomenon of TV ghost in terms of a mathematical model and explain a procedure of producing a composite image which consists of original and ghost components. Secondly we describe the definition of power cepstrum and formulate the cepstrum of the composite image. After that, we introduce a cepstral difference between composite and original images and discuss some properties of the cepstral difference. Furthermore we consider the role of an exponential window function in the cepstral analysis of composite images. The computer simulated results for some test images show that the lag of ghost component in each image can be detected effectively by the cepstral difference even when the ghost component appears slightly.