Plugins CrossCor_1D and CrossCor_2D calcualte the auto- and cross- correlations between datasets over offsets in time (Dt) and angle (Dq). The correlation function is :
CrossCor_2D Calculates the correlation function as shown above, as a function of both Dt and Dq. CrossCor_1D calculates the correlation function for Dq=0, as a function of Dt only.
Both plugins require the data output of LE_Velocity and/or
Intensity_Ribbon as inputs. If the two datasets are the same, an
autocorrelation will be calculated, otherwise a cross-correlation will
be calculated.
When either plugin is run
it will prompt the user to input necessary data:
The required parameters are:
N: number of frames in the stack
dt: time per frame, measured in s
qmin: the minimum angle over which to analyze data, in degrees
M, the number of angles to analyze
The user is then prompted to choose two files to be analyzed. The input data files must contain matrices of data N x 360, where N is the number of frames of the image stack. The user can then save a data file containing correlation functions.
Ouput file:
The output for CrossCor_1D will be in columns with the data formatted (Dt, cf*g), while CrossCor_2D will be a matrix of data (N-1) x (M-1), where the column number indicates the time offset, and the row number indicates the angle offset.
References:
G. L. Ryan, N. Watanabe, D. Vavylonis,
"Image Analysis Tools to Quantify Cell Shape and Protein Dynamics near the Leading Edge," Cell
Structure and Function (2013).
G. L. Ryan, H. Petroccia, N. Watanabe, D. Vavylonis,
"Excitable Actin Dynamics in Lamellipodial Protrusion and Retraction,"
Biophys. J. 102:1493-1502 (2012).
