How to gauss-filter (blur) a floating point numpy array

Question

I have got a numpy array a of type float64. How can I blur this data with a Gauss filter?

I have tried

from PIL import Image,          


        

Answer 1

Here is my approach using only numpy. It is prepared with a simple 3x3 kernel, minor changes could make it work with custom sized kernels.

def blur(a):
    kernel = np.array([[1.0,2.0,1.0], [2.0,4.0,2.0], [1.0,2.0,1.0]])
    kernel = kernel / np.sum(kernel)
    arraylist = []
    for y in range(3):
        temparray = np.copy(a)
        temparray = np.roll(temparray, y - 1, axis=0)
        for x in range(3):
            temparray_X = np.copy(temparray)
            temparray_X = np.roll(temparray_X, x - 1, axis=1)*kernel[y,x]
            arraylist.append(temparray_X)

    arraylist = np.array(arraylist)
    arraylist_sum = np.sum(arraylist, axis=0)
    return arraylist_sum