add dtype=object to ragged arrays to prevent deprecation warning

Author: rmislam

pysift.py

@@ -77,7 +77,7 @@ def generateGaussianImages(image, num_octaves, gaussian_kernels):
         gaussian_images.append(gaussian_images_in_octave)
         octave_base = gaussian_images_in_octave[-3]
         image = resize(octave_base, (int(octave_base.shape[1] / 2), int(octave_base.shape[0] / 2)), interpolation=INTER_NEAREST)
-    return array(gaussian_images)
+    return array(gaussian_images, dtype=object)
 
 def generateDoGImages(gaussian_images):
     """Generate Difference-of-Gaussians image pyramid
@@ -90,7 +90,7 @@ def generateDoGImages(gaussian_images):
         for first_image, second_image in zip(gaussian_images_in_octave, gaussian_images_in_octave[1:]):
             dog_images_in_octave.append(subtract(second_image, first_image))  # ordinary subtraction will not work because the images are unsigned integers
         dog_images.append(dog_images_in_octave)
-    return array(dog_images)
+    return array(dog_images, dtype=object)
 
 ###############################
 # Scale-space extrema related #