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Norfello Inc. Announces a New Curvature Correction Algorithm That Creates ebooks from Paper Books with Any Camera

Monday 31. January 2011 - Norfello Inc. today announced a research breakthrough in algorithmic curvature correction from 2D images.

“Knowing how popular ebook readers and tablets, such as Kindle and iPad are currently, the demand for content is obvious. Using a software approach to digitize paper content, enables us to crowd source some of the bottlenecks that are currently holding users from consuming more content in ebook form.”, said Tuomas Rasila, founder of Norfello Inc.
After months of algorithmic research, real world testing and software development Norfello has developed a way to automatically correct page curvature from 2D images. The main application for this new algorithm is to enable non-destructive book scanning without any special hardware. “We have been using consumer grade digital cameras and iPhone 4’s camera in our tests and we are happy with the results.”, said Jarno Ruokokoski, the lead developer of the new algorithm.
Norfello published images showcase how the algorithm works. It takes one image of a spread of a book as an input and produces two images, one of each page. In the pages produced all the curvature of text lines is removed. These images are not modified by hand, so the text area detection, cropping and whitening are also native parts of the software.
“The algorithm searches two text areas (one for each page), and for each area left and right margins. Next it approximates from a blurred image the baselines of the lines of text. The algorithm computes the corrected baselines by using spline fitting iteratively. Finally, the algorithm creates triangulation on the image based on the baselines, and draws the triangles to a new image by using affine transformations such that every baseline is a straight line in the new image and both the margins are vertical.”, explained Jarno Ruokokoski.
“This algorithm will be included in our existing App, DocScanner Mac, but we will also create a new application that focuses solely on scanning books with a clutter free user interface that makes book scanning as productive as possible and integrates with Amazon Kindle via Whispersync and iBooks. Carrying lots of books just isn’t possible all the time, but people tend to always carry their Kindles and iPads with them.”, said Tuomas Rasila