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### How to merge nearby rectangles

I am working on character segmentation and looking to merge nearby characters into a box. I have successfully found the contours but I am not sure how to find a straight line between the top and bottom points.

def findContours(self, image):
contour_img = image.copy()
vis = image.copy()
vis = cv2.cvtColor(vis, cv2.COLOR_GRAY2BGR)
_, contours, hierarchy = cv2.findContours(contour_img, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)

contoursBBS = []
for contour in contours:
[x, y, w, h] = cv2.boundingRect(contour)

if w > 100 or h < 8:
continue

contoursBBS.append([x, y, w, h, w*h])
contoursBBS = np.array(contoursBBS)

# reject outliers based on width, height, and area
rejectH = self.rejectOutliers(contoursBBS, 3, m=4)
rejectW = self.rejectOutliers(rejectH, 2, m=4)
rejectA = self.rejectOutliers(rejectW, 4, m=4)

contourRects = []
for c in rejectA:
[x, y, w, h, a] = c
if w < 9 or h < 15 or a < 300 or a > 6000:
continue
contourRects.append(c)

for i, rect in enumerate(contourRects):
[x, y, w, h, a] = rect
topCenter, bottomCenter = (int((2*x + w)/2), int(y)), (int((2*x + w)/2), int(y+h))

print("X: {:4d}  Y:  {:4d}  W: {:4d}  H: {:4d}  A: {:4d}".format(x, y, w, h, a))

cv2.rectangle(vis, (x, y), (x+w, y+h), (0, 255, 0), 2)
cv2.circle(vis, topCenter, 2, (0, 0, 255), 2)
cv2.circle(vis, bottomCenter, 2, (0, 0, 255), 2)


Result

What I am hoping to achieve

### How to merge nearby rectangles

I am working on character segmentation and looking to merge nearby characters into a box. I have successfully found the contours but I am not sure how to find a straight line between the top and bottom points.

def findContours(self, image):
contour_img = image.copy()
vis = image.copy()
vis = cv2.cvtColor(vis, cv2.COLOR_GRAY2BGR)
_, contours, hierarchy = cv2.findContours(contour_img, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)

contoursBBS = []
for contour in contours:
[x, y, w, h] = cv2.boundingRect(contour)

if w > 100 or h < 8:
continue

contoursBBS.append([x, y, w, h, w*h])
contoursBBS = np.array(contoursBBS)

# reject outliers based on width, height, and area
rejectH = self.rejectOutliers(contoursBBS, 3, m=4)
rejectW = self.rejectOutliers(rejectH, 2, m=4)
rejectA = self.rejectOutliers(rejectW, 4, m=4)

contourRects = []
for c in rejectA:
[x, y, w, h, a] = c
if w < 9 or h < 15 or a < 300 or a > 6000:
continue
contourRects.append(c)

for i, rect in enumerate(contourRects):
[x, y, w, h, a] = rect
topCenter, bottomCenter = (int((2*x + w)/2), int(y)), (int((2*x + w)/2), int(y+h))

print("X: {:4d}  Y:  {:4d}  W: {:4d}  H: {:4d}  A: {:4d}".format(x, y, w, h, a))

cv2.rectangle(vis, (x, y), (x+w, y+h), (0, 255, 0), 2)
cv2.circle(vis, topCenter, 2, (0, 0, 255), 2)
cv2.circle(vis, bottomCenter, 2, (0, 0, 255), 2)


Result

What I am hoping to achieve

Some test images (requested by @supra56)

1. https://ibb.co/bgtyypp
2. https://ibb.co/XtdHgWg
3. https://ibb.co/5R4QVTR
4. https://ibb.co/gD8KymR (very challenging)
5. https://ibb.co/k5YDT1Q