C# Image Deskew

Question

Has anyone seen any image deskew algorithms in c#? I have found: http://www.codeproject.com/KB/graphics/Deskew_an_Image.aspx

but unfortunately, it doesn't do very much for images without text. I am specifically trying to auto deskew an image of a book with solid edges, but minimal text.

Has anyone seen anything that may be able to do this?

Answer 1

The basic algorithm is to use a Hough transform to find the lines and then try to make most of the lines horizontal. Here's some basic code http://www.sydlogan.com/deskew.html

For your situation, you might want to target the transform at a piece of the image you know might have the best information. For example if there's a page border -- I'd need to see an example to give better advice.

Disclaimer, I work at Atalasoft.

Our DotImage toolkit has it built in for .NET and is runtime royalty-free for desktop applications. Code would be:

 AtalaImage img = new AtalaImage("imagefile.tif");
 AutoDeskewCommand cmd = new AutoDeskewCommand();
 AtalaImage resultImage = cmd.Apply(img).Image;
 resultImage.Save("result.tif", new TiffEncoder(), null);

Or something similar for multipage or other types of images.

We show how to integrate it with our viewer control in this video (at 1:14)

http://www.atalasoft.com/products/dotimage/tutorials/capture/lesson4.aspx

The videos are part of a series of building a document scanning application:

http://www.atalasoft.com/products/dotimage/tutorials/capture/lesson1.aspx http://www.atalasoft.com/products/dotimage/tutorials/capture/lesson2.aspx http://www.atalasoft.com/products/dotimage/tutorials/capture/lesson3.aspx