scalar = | pearsonCorrelationCoefficient2d (inImg1,inImg2) |
computes the Pearson correlation coefficient in the image
The Pearson correlation coefficient, also known as Pearson colocalization, is a linear correlation measure between the two input images InImg1 and InImg2. This coefficient is calculated with the following formula :
Where is the image domain,
is the mean intensity of
and
is its standard deviation.
Two wrappers can be called : the pearsonCorrelationCoefficient2d wrapper is only used to compute the Pearson coefficient on a grey level 2d image, whereas the multiSlice_pearsonCorrelationCoefficient2d wrapper must be used for more complex data (volume, sequence and/or color). In the second case, a coefficient is calculated for each 2d plan forming the input images.
This algorithm is equivalent to compute the sum on each 2d plan of the resulting image of Pearson colocalization mapping 2d.