Calculating the correlation coefficient of one pixel with the surrounding pixels in same raster

I am working on a problem in which I have 20 years of daily data (raster). I have a point shapefile with 123 point locations. Now first I need to select the particular pixel on which the point location is falling and find the correlation coefficient between that pixel and pixels in the 300km radius area of that pixel. This has to be done for all the 123 point locations on all the raster files of daily data (ignoring no data pixels).