You should just be able to use np.asarray
directly on the memoryview itself, so something like:
np.asarray(my_memview)
should work. For example if your cython source file contains this:
import numpy as np
cimport numpy as np
def test(double[:,:] x):
print type(x)
print type(np.asarray(x))
Then after compiling it, you should be able to do the following from the python side:
a = np.random.normal(size=(5,5))
test(a)
Which produces the following output:
<type '_cython_magic_0182fca918bfa3618c3553e51b13e8ba._memoryviewslice'>
<type 'numpy.ndarray'>
Note: I'm using the cythonmagic extension for IPython.