wav_th {EFDR}

Indices of wavelets exceeding a given threshold

Description

This function is primarily used for testing the power of a method in the wavelet domain. Given an image, the discrete wavelet transform is found. The indices of the coefficients which exceed a certain threshold are then considered the 'signal' for testing purposes.

Usage

wav_th(Z, wf = "la8", J = 2, th = 1)

Arguments

Z

image of size n1 by n2 where n1,n2 have to be powers of two

wf

type of wavelet to employ. Please see waveslim::wave.filter for a full list of wavelet names

J

number of resolutions to employ in the wavelet decomposition

th

threshold

Value

Indices of wavelet coefficients in a vector

References

Shen, X., Huang, H.-C., and Cressie, N. 'Nonparametric hypothesis testing for a spatial signal.' Journal of the American Statistical Association 97.460 (2002): 1122-1140.

Examples

Z <- test_image(h = 0.5, r = 14, n1 = 64)$z
print(wav_th(Z,wf="la8",J=3,th=0.5))