pythonRLSA 0.0.1

Python Run Length Smoothing Algorithm for Document Processing

Project Description

- RUN LENGTH SMOOTHING ALGORITHM(RLSA) is a method mainly used for block segmentation and text discrimination.
- It mainly uses in Document Image Processing to extract out the ROI(region of interest) like block-of-text/title/content with applied heuristics.

Install requirements

- pip install -r requirements.txt

Install

- pip install pythonRLSA

Input & Output

Output of 3 cases with value "10" can be seen here

More results can be seen here

How it works

- '255'(white pixel) wil be converted to '0'(black pixel) in a image, if the number of adjacent 255's are less than the predefined limit "value".
- The "value" varies among the different images.

Sample Test Case

- value = 3
- input - [0, 0, 255, 255, 255, 0, 0, 255, 0, 0, 255, 0, 255]
- output - [0, 0, 255, 255, 255, 0, 0, 0, 0, 0, 0, 0, 255]

To test

- python pythonRLSA/test_rlsa_unittest.py -v

Unittest Results

- test_bool (__main__.TestRLSA) ... ok
- test_image (__main__.TestRLSA) ... Image must be an numpy ndarray and must be in binary ... ok
- test_rlsa_hori (__main__.TestRLSA) ... ok
- test_rlsa_hori_vert (__main__.TestRLSA) ... ok
- test_rlsa_vert (__main__.TestRLSA) ... ok
- test_value (__main__.TestRLSA) ... ok

---

Ran 6 tests in 0.003s

OK

Prerequisites

- python3.5+
- Image must be a binary ndarray(255's/1's/0's)
- Must pass a predefined limit, a certain integer "value"

Method

- rlsa

Parameters

- image - numpy.ndarray(required)
- horizantal - boolean(required)
- vertial - boolean(required)
- value - any positive integer(int)(required)

IPython code to convert Image to Binary and RLSA usage

- # convert the image to binary
- import cv2
- image = cv2.imread('test_images/image.jpg')
- gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
- (thresh, image_binary) = cv2.threshold(gray, 150, 255, cv2.THRESH_BINARY | cv2.THRESH_OTSU)
- # function call
- from pythonRLSA import rlsa
- image_rlsa_horizontal = rlsa.rlsa(image_binary, True, False, 10)

Bugs/Errors

Please ensure that you have updated pip to the latest version before installing pythonRLSA.

If you find any bugs/errors in the usage of above code, please raise an issue through Github or send an email to [e-mail] with a clear example that can reproduce the issue.