Wavelet-based separation of nonlinear show-through and bleed-through image mixtures

(Abstract, Matlab Code)

 

 

Acquired                                                            Separated

page images                                                         page images

 

 

 

 

Reference:

 

M. S. C. Almeida and L. B. Almeida, "Wavelet-based separation of nonlinear show-through and bleed-through image mixtures ", Neurocomputing, vol. 72, pp. 57-70 December 2008. (PDF)

 

 

 

Abstract:

This work addresses the separation of the nonlinear real-life mixture of images that occurs when a page of a document is scanned or photographed and the back page shows through. This effect can be due to partial paper transparency (show-through) and/or to bleeding of the ink through the paper (bleed-through). These two causes usually lead to mixtures with different characteristics. We propose a separation method based on the fact that the high-frequency components of the images are sparse and are stronger on one side of the paper than on the other one. The same properties were already used in nonlinear denoising source separation (DSS). However, we developed significant improvements that allow us to achieve a competitive separation quality by means of a one-shot processing, with no iteration. The method does not require the sources to be independent or the mixture to be invariant, and is suitable for separating mixtures such as those produced by bleed-through, for which we do not have an adequate physical model.

 

 

Matlab Code:  alignment routines, separation routines

If you find any bug, please report it to me: M. S. C. Almeida. Thank you!

 

 

Data:

 

·         Tracing paper images:  Results (zip file). The mixtures can be found through the home page of Prof. Luís Borges de Almeida (here). 

 

·         Air mail letter (.rar ):  front page, back page, back page (flipped),

front page (aligned), back page (aligned), back page (aligned, flipped)

recovered front page, recovered back page,  recovered back page (flipped)

 

·         Old partitures (.rar ):   #1: front page, back page, back page (flipped)

recovered front page ( block ),   recovered front page ( block ), recovered front page (block, flipped).

 

   #2: front page, back page, back page (flipped)

recovered front page ( block ),   recovered front page ( block ),     recovered front page (block, flipped).

 

 

 

License:  This code and these data sets are copyright of Luís B. Almeida and Mariana S.C. Almeida. Free permission is given for their use for nonprofit research purposes. Any other use is prohibited, unless a license is previously obtained. To obtain a license please contact Luís B. Almeida or Mariana S.C. Almedia

 

 

 

See, here, another method for separating linear/nonlinear show-through and bleed-through mixtures.

 

 

 

These packages are compressed with win-rar. Download it here.