Abstract book (pdf) - ICPR 2010

09:00-11:10, Paper WeAT8.43
Transition Thresholds for Binarization of Historical Documents
Ramírez-Ortegón, Marte Alejandro, Free Univ. of Berlin
Rojas, Raul, Freie Univ. Berlin
This paper extends the transition method for binarization based on transition pixels, a generalization of edge pixels. This
method originally computes transition thresholds using the quantile thresholding algorithm, that has a critical parameter.
We achieved an automatic version of the transition method by computing the transition thresholds with the Rosin’s algorithm.
We experimentally tested four variants of the transition method combining the density and cumulative distribution
functions of transition values, with gray-intensity thresholds based on the normal and lognormal density functions. The
results of our experiments show that these unsupervised methods yields superior binarization compared with top-ranked
algorithms.
09:00-11:10, Paper WeAT8.44
Image Quality Metrics: PSNR vs. SSIM
Horé, Alain, Sherbrooke Univ.
Ziou, Djemel, Sherbrooke Univ.
In this paper, we analyse two well-known objective image quality metrics, the peak-signal-to-noise ratio (PSNR) as well
as the structural similarity index measure (SSIM), and we derive a simple mathematical relationship between them which
works for various kinds of image degradations such as Gaussian blur, additive Gaussian white noise, jpeg and jpeg2000
compression. A series of tests realized on images extracted from the Kodak database gives a better understanding of the
similarity and difference between the SSIM and the PSNR.
09:00-11:10, Paper WeAT8.45
Coarse Scale Feature Extraction using the Spiral Architecture Structure
Coleman, Sonya, Univ. of Ulster
Scotney, Bryan, Univ. of Ulster
Gardiner, Bryan, Univ. of Ulster
The Spiral Architecture has been developed as a fast way of indexing a hexagonal pixel-based image. In combination with
spiral addition and spiral multiplication, methods have been developed for hexagonal image processing operations such
as translation and rotation. Using the Spiral Architecture as the basis for our operator structure, we present a general approach
to the computation of adaptive coarse scale Laplacian operators for use on hexagonal pixel-based images. We evaluate
the proposed operators using simulated hexagonal images and demonstrate improved performance when compared
with rectangular Laplacian operators such as Marr-Hildreth
09:00-11:10, Paper WeAT8.46
Visual Perception Driven Registration of Mammograms
Boucher, Arnaud, Univ. Paris Descartes
Cloppet, Florence, Paris Descartes Univ.
Vincent, Nicole, Paris Descartes Univ.
Jouve, Pierre Emmanuel, Fenics Company
This paper aims to develop a methodology to register pairs of temporal mammograms. Control points based on anatomical
features are detected in an automated way. Thereby, image semantic is used to extract landmarks based on these control
points. A referential is generated from these control points based on this referential the studied images are realigned using
different levels of observation leading to both rigid and pseudo non-rigid transforms according to expert mammogram
reading.
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