  We introduce a method to measure the entanglement entropy using a wavelet
analysis. In the method we perform the two-dimensional Haar wavelet transform
of configuration of Fortuin-Kasteleyn (FK) clusters. The configuration
represents a direct snapshot of spin-spin correlations since spin degrees of
freedom are traced out in FK representation. A snapshot of FK clusters loses
image information at each coarse-graining process by the wavelet transform. We
show that the loss of image information measures the entanglement entropy in
the Potts model.
