Clock ORC
October 2019
Machine-learning-OCR
Machine learning Optical Character Recognition (OCR) project. Read the time on a digital clock by inputting an image.
The process
Step 0 : The input image
We want to extract the time from an image.
Step 1 : Homographic transformation
Look for the similarity between the reference image and the input image. The goal here is to revert the effect of perspective distortion in order to get a flat image and getting rid of the useless parts of the image.
Step 2 : Output from the homography
If the homography is a success then the image is wrapped and transformed according to the reference homography else the image is the input image.
Step 3 : Masking the image
We create a binary image from the previous image according to a color threshold
Step 4 : Process of analysis
We extract each element of the binary image, then the trained model compare these shapes with a bank of images of digits. Then the algorithm returns the corresponding digit.
The trainning process
To train ou model we have a bank of images of digits sorted and labeled. We can then use a classification algorithm to train the model.