Comparison of Harmonic, Geometric and Arithmetic means for change detection in SAR time series
نویسندگان
چکیده
The amplitude distribution in a SAR image can present a heavy tail. Indeed, very high–valued outliers can be observed. In this paper, we propose the usage of the Harmonic, Geometric and Arithmetic temporal means for amplitude statistical studies along time. In general, the arithmetic mean is used to compute the mean amplitude of time series. In this study, we will show that comparing the behaviour of the Harmonic, Geometric and Arithmetic means, enables a change detection method along SAR time series. 1 Different means for SAR imagery Different temporal means can be computed between two amplitude SAR images. In this paper, we will focus on the Harmonic Mean HM, the Geometric Mean GM, and the Arithmetic Mean AM : HM[x, y] = 2 1 x + 1 y , (1)
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