diff --git a/skimage/morphology/_skeletonize_cy.pyx b/skimage/morphology/_skeletonize_cy.pyx
index 805cdad7..10e70d98 100644
--- a/skimage/morphology/_skeletonize_cy.pyx
+++ b/skimage/morphology/_skeletonize_cy.pyx
@@ -20,7 +20,7 @@ cimport numpy as cnp
 
 
 def _skeletonize_loop(cnp.uint8_t[:, ::1] result,
-                      cnp.uint8_t[:] i, cnp.uint8_t[:] j,
+                      Py_ssize_t[:] i, Py_ssize_t[:] j,
                       cnp.int32_t[:] order, cnp.uint8_t[:] table):
     """
     Inner loop of skeletonize function
@@ -207,4 +207,4 @@ def _table_lookup_index(cnp.uint8_t[:, ::1] image):
             indexer[i - 1, j_shape - 1] += 128
             indexer[i, j_shape - 1] += 16
             indexer[i + 1, j_shape - 1] += 2
-    return indexer
+    return np.asarray(indexer)
diff --git a/skimage/transform/_warps_cy.pyx b/skimage/transform/_warps_cy.pyx
index 0eb7efdd..5dc2ffd0 100644
--- a/skimage/transform/_warps_cy.pyx
+++ b/skimage/transform/_warps_cy.pyx
@@ -123,4 +123,4 @@ def _warp_fast(cnp.ndarray image, cnp.ndarray H, output_shape=None,
             out[tfr, tfc] = interp_func(&img[0, 0], rows, cols, r, c,
                                         mode_c, cval)
 
-    return out
+    return np.asarray(out)