openpiv.pyprocess.find_pixel_peak_position

openpiv.pyprocess.find_pixel_peak_position(corr, sig2noise_method='peak2peak', sig2noise_lim=1.0)

Find pixel approximation of the correlation peak.

This function returns a subpixels approximation of the correlation peak by fitting a two dimensional Gaussian curve in a 3x3 square region around the correlation peak.

Parameters :

corr : np.ndarray

the correlation map

sig2noise_method : string

defines the method of signal-to-noise-ratio measure, (‘peak2peak’ or ‘peak2mean’)

sig2noise_lim : float

the minimum signal/noise ratio that can be accepted

default_peak_position : two elements tuple

the default peak position, if something goes wrong in the peak detection algorithm. Default is (corr.shape[0]/2,corr.shape[1]/2)

Returns :

peak_position : two elements tuple

the sub-pixel approximation of the correlation peak

sig2noise : float

the signal to noise ratio