ValueError: could not broadcast input array from shape (16,18,3) into shape (16) - numpy

Question

I was trying to instance segment my RGB images using pixellib library. However, I encountered the problem from segmentImage function. From stacktrace, I found the issue within init.py, and I have no idea why it needs to broadcast from 3D arrays to 1D. 20 Images from another folder I tried earlier didn't counter any of these.
P.S. This was my first question on StackOverflow. if I miss any necessary details, please let me know.
for file in os.listdir(test_path):
abs_test_path = os.path.join(test_path, file)
if file.endswith('.jpg'):
filename = os.path.splitext(file)[0]
if (os.path.isfile(abs_test_path)):
out_path = out_seg_path + filename
segment_image.segmentImage(abs_test_path, show_bboxes=True,
save_extracted_objects=True,
extract_segmented_objects=True)
im_0 = cv2.imread('segmented_object_1.jpg')
cv2.imwrite(out_path + '_1.jpg', im_0)
im_1 = cv2.imread('segmented_object_2.jpg')
cv2.imwrite(out_path + '_2.jpg', im_1)
This is my error
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
<ipython-input-4-835299843033> in <module>
15
16 segment_image.segmentImage(abs_test_path, show_bboxes=True,
---> 17 save_extracted_objects=True, extract_segmented_objects=True)
18
19 # segment_image.segmentImage('segmented_object_1.jpg', show_bboxes=True, output_image_name=out_path + '_1.jpg',
~\anaconda3\envs\mask_rcnn\lib\site-packages\pixellib\instance\__init__.py in segmentImage(self, image_path, show_bboxes, extract_segmented_objects, save_extracted_objects, mask_points_values, output_image_name, text_thickness, text_size, box_thickness, verbose)
762 cv2.imwrite(save_path, extracted_objects)
763
--> 764 extracted_objects = np.array(ex, dtype=object)
765
766 if mask_points_values == True:
ValueError: could not broadcast input array from shape (16,18,3) into shape (16)

Answer 1

There isn't enough information to help you.
I don't know what segment_image.segmentImage is, or what it expects. And I don't have your jpg file to test.
I have an idea of why the problem line raises this error, but since it occurs in an unknown function I can't suggest any fixes.
extracted_objects = np.array(ex, dtype=object)
ex probably is a list of arrays, arrays that match in some some dimensions but not others. It's trying to make an object dtype array of those arrays, but due to the mix of shapes it raises an error.
An simple example that raises the same error:
In [151]: ex = [np.ones((3, 4, 3)), np.ones((3, 5, 3))]
In [152]: np.array(ex, object)
Traceback (most recent call last):
Input In [152] in <module>
np.array(ex, object)
ValueError: could not broadcast input array from shape (3,4,3) into shape (3,)