The Open ICR Image Pre-processor

An Python script used to pre-process images of individual handwritten characters to increase OCR/ICR accuracy Part of the Open ICR Project - http://opensource.newmediaist.com/open-source-icr.html

The purpose of this image pre-processor is to "sanitize and standardize" the input image as much as possible to prepare it for the recognition engine. The image preprocessor has the following dependencies:

• Python & the following Python Plugins:
• OpenCV
• NumPy
• sciPy
• zhangsuen

The following is a short summary of the different modifications the image pre-processor makes to the image:

1. Remove borders around the character (i.e. from imperfect character extraction)
2. Median filtering is applied to remove salt and pepper type noise
3. Character image is cropped down to borders of written character
4. Character image is scaled to a standard set of dimensions
5. Character image is thinned using Zhang Suen algo
6. White space padding added around the image to prepare for next stage
7. Erosion is added to the character image to join small gaps

Usage

python preprocessor.py -o original.png-d ~path_for_output\filename.png

Code licensed under Apache License v2.0