How to split the image into chunks without breaking character - python - image-processing

Question

I am trying to read image from the text.
I am getting better result if I break the images into small chunks but the problem is when i try to split the image it is cutting/slicing my characters.
code I am using :
from __future__ import division
import math
import os
from PIL import Image
def long_slice(image_path, out_name, outdir, slice_size):
"""slice an image into parts slice_size tall"""
img = Image.open(image_path)
width, height = img.size
upper = 0
left = 0
slices = int(math.ceil(height/slice_size))
count = 1
for slice in range(slices):
#if we are at the end, set the lower bound to be the bottom of the image
if count == slices:
lower = height
else:
lower = int(count * slice_size)
#set the bounding box! The important bit
bbox = (left, upper, width, lower)
working_slice = img.crop(bbox)
upper += slice_size
#save the slice
working_slice.save(os.path.join(outdir, "slice_" + out_name + "_" + str(count)+".png"))
count +=1
if __name__ == '__main__':
#slice_size is the max height of the slices in pixels
long_slice("/python_project/screenshot.png","longcat", os.getcwd(), 100)
Sample Image : The image i want to process
Expected/What i am trying to do :
I want to split every line as separate image without cutting the character
Line 1:
Line 2:
Current result:Characters in the image are cropped
I dont want to cut the image based on pixels since each document will have separate spacing and line width
Thanks
Jk

Answer 1

Here is a solution that finds the brightest rows in the image (i.e., the rows without text) and then splits the image on those rows. So far I have just marked the sections, and am leaving the actual cropping up to you.
The algorithm is as follows:
Find the sum of the luminance (I am just using the red channel) of every pixel in each row
Find the rows with sums that are at least 0.999 (which is the threshold I am using) as bright as the brightest row
Mark those rows
Here is the code that will return a list of these rows:
def find_lightest_rows(img, threshold):
line_luminances = [0] * img.height
for y in range(img.height):
for x in range(img.width):
line_luminances[y] += img.getpixel((x, y))[0]
line_luminances = [x for x in enumerate(line_luminances)]
line_luminances.sort(key=lambda x: -x[1])
lightest_row_luminance = line_luminances[0][1]
lightest_rows = []
for row, lum in line_luminances:
if(lum > lightest_row_luminance * threshold):
lightest_rows.add(row)
return lightest_rows
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 ... ]
After colouring these rows red, we have this image: