вы можете использовать поиск контуров и связать их с рамкой.
image = cv2.imread("filename")
image = cv2.fastNlMeansDenoisingColored(image,None,10,10,7,21)
gray = cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
res,thresh = cv2.threshold(gray,150,255,cv2.THRESH_BINARY_INV) #threshold
kernel = cv2.getStructuringElement(cv2.MORPH_CROSS,(3,3))
dilated = cv2.dilate(thresh,kernel,iterations = 5)
val,contours, hierarchy =
cv2.findContours(dilated,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)
coord = []
for contour in contours:
[x,y,w,h] = cv2.boundingRect(contour)
if h>300 and w>300:
continue
if h<40 or w<40:
continue
coord.append((x,y,w,h))
coord.sort(key=lambda tup:tup[0]) # if the image has only one sentence sort in one axis
count = 0
for cor in coord:
[x,y,w,h] = cor
t = image[y:y+h,x:x+w,:]
cv2.imwrite(str(count)+".png",t)
print("number of char in image:", count)