import cv2
import numpy as np

img = cv2.imread("oYeWE.png", cv2.IMREAD_COLOR)

gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

medians = np.median(gray, axis=1)
borders = np.where(np.median(gray, axis=1) < 255)[0]
borders = np.hstack([[0], borders, [gray.shape[0]]])

locations = np.where(np.diff(borders) > 1)[0]

regions = []
for l in locations:
    regions.append(img[borders[l]:borders[l+1],:])

for i, region in enumerate(regions):
    cv2.imshow('Section%d' % i, region)

cv2.waitKey()