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by blackjackfoe 564 days ago
This project was really my first decent introduction to computer vision and machine learning (along with that of those who helped me in various ways; none of them desired to be credited here other than the guy who collected some of the data for me.)

It was definitely a successful learning exercise, and it's made me more confident tackling some other problems I've had in mind for awhile.
2 comments
spookie 564 days ago
To help you out if you're interested:

- a smeared gaussian in one axis and another in another axis can really help segmenting chars, finding lines of text in OCR

- You can unshear chars using the Radon or Hough transform as a basis to understand the angle

Went through MNIST a few weeks ago and I agree it's interesting!

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blackjackfoe 564 days ago
I am always interested! Thank you for the tips, I'll definitely research these.
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sorenjan 564 days ago
Shearing is a linear operation that should be trivial for a NN to learn. Have you found that unshearing is actually useful? Was it to feed the image to an existing OCR program?
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normie3000 564 days ago
How did this project help you to learn computer vision? I'd also like to write a basic captcha solver as an intro, but superficially this project just looks like a dump of generated code.
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blackjackfoe 564 days ago
What do you mean by "generated code"? All of the code in the linked GitHub repo was written by me, with the assistance of a couple friends who helped here and there, but didn't request to be credited.

I learned a lot because I had to do a ton of research and experimentation (fancy word for trial-and-error) to write the code and have it work as I expected.

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normie3000 564 days ago
I think there's been a misunderstanding. I didn't understand you were the author of the linked article, and read the following exchange to mean you'd found the code at https://github.com/drunohazarb/4chan-captcha-solver to be a helpful introduction:

> > I've built 3 iterations of captcha solvers for that crappy website based on https://github.com/drunohazarb/4chan-captcha-solver/issues/1

> This project was really my first decent introduction to computer vision and machine learning

I see now that your code is linked from the article, and looks really informative - thanks for sharing!

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