In this tutorial, you will create an automatic Sudoku puzzle solver using OpenCV, Deep Learning, and Optical Character Recognition (OCR).
My wife is a huge Sudoku nerd. Every time we travel, whether it be a 45-minute flight from Philadelphia to Albany or a 6-hour transcontinental flight to California, she always has a Sudoku puzzle with her.
The funny thing is, she prefers the printed Sudoku puzzle books. She hates the digital/smartphone app versions and refuses to play them.
I’m not a big puzzle person myself, but one time, we were sitting on a flight, and I asked:
How do you know if you solved the puzzle correctly? Is there a solution sheet in the back of the book? Or do you just do it and hope it’s correct?
Apparently, that was a stupid question to ask, for two reasons:
- Yes, there is a solution key in the back. All you need to do is flip to the back of the book, locate the puzzle number, and see the solution.
- And most importantly, she doesn’t solve a puzzle incorrectly. My wife doesn’t get mad easily, but let me tell you, I touched a nerve when I innocently and unknowingly insulted her Sudoku puzzle solving skills.
She then lectured me for 20 minutes on how she only solves “level 4 and 5 puzzles,” followed by a lesson on the “X-wing” and “Y-wing” techniques to Sudoku puzzle solving. I have a Ph.D in computer science, but all of that went over my head.
But for those of you who aren’t married to a Sudoku grand master like I am, it does raise the question:
Can OpenCV and OCR be used to solve and check Sudoku puzzles?
If the Sudoku puzzle manufacturers didn’t have to print the answer key in the back of the book and instead provided an app for users to check their puzzles, the printers could either pocket the savings or print additional puzzles at no cost.
The Sudoku puzzle company makes more money, and the end users are happy. Seems like a win/win.
And from my perspective, perhaps if I publish a tutorial on Sudoku, maybe I can get back in my wife’s good graces.
#opencv
