Regionprops (skimage.measure) for Video in Python - python-3.x

Question

I got a piece of code on internet that 'Label image regions' and tried to run it over a video , but all I get is first frame and than an error after closing the first frame window " max() arg is an empty sequence" from line" plt.tight_layout() of my code. I am trying to get label for all the frames in my video instead of single image example as shown in the given example above (link). Basically the code should display/plot all the frames with labels.
Any help will be really useful.Please find my code below
import cv2
import numpy as np
from matplotlib import pyplot as plt
import time
import matplotlib.patches as mpatches
from skimage import data
from skimage.filters import threshold_otsu
from skimage.segmentation import clear_border
from skimage.measure import label, regionprops
from skimage.morphology import closing, square
from skimage.color import label2rgb
cap = cv2.VideoCapture('test3.mp4')
fig, ax = plt.subplots(figsize=(10, 6))
while(1):
t = time.time()
ret, frame2 = cap.read()
image = cv2.cvtColor(frame2, cv2.COLOR_BGR2GRAY)
thresh = threshold_otsu(image)
bw = closing(image > thresh, square(3))
# remove artifacts connected to image border
cleared = clear_border(bw)
# label image regions
label_image = label(cleared)
image_label_overlay = label2rgb(label_image, image=frame2)
x = regionprops(label_image)
area2 = [r.area for r in x]
print(area2)
ax.imshow(image_label_overlay)
for region in regionprops(label_image):
# take regions with large enough areas
if region.area >= 100:
# draw rectangle around segmented coins
minr, minc, maxr, maxc = region.bbox
rect = mpatches.Rectangle((minc, minr), maxc - minc, maxr -minr,
fill=False, edgecolor='red', linewidth=2)
ax.add_patch(rect)
ax.set_axis_off()
plt.tight_layout()
plt.show()
if cv2.waitKey(1) & 0xFF == ord('q'):
break
cap.release()
cv2.destroyAllWindows()

Answer 1

Wola!
And the solution is:
1.) Error rectification: "max() arg is an empty sequence" from line plt.tight_layout() can be removed using fig.tight_layout rather than plt.tight_layout. Because after I was closing the first frame of video (that was not updating, well that's another problem I am still pondering on!!) the figure was empty and it was raising an exception as tight.layout trying to run on an empty figure.
2.) Running Label image regions code for video is made possible if you replace line
rect = mpatches.Rectangle((minc, minr), maxc - minc+50, maxr - minr+50,fill=False, edgecolor='red', linewidth=2)
ax.add_patch(rect)
ax.set_axis_off()
plt.tight_layout()
plt.show()
with
cv2.rectangle(frame2, (minc, minr), (minc +maxc - minc , minr + maxr - minr), (0, 255, 0), 2)
cv2.imshow('ObjectTrack', frame2) # this line outside the if loop
Basically display the video the way it is in simple Capture Video from Camera program of Python.