"Estimation of appropriate parameter values for document binarization techniques"
International Journal of Robotics and Automation, Vol. 24, No. 1, 2009.
Most of the existing document-binarization
techniques deal with many parameters that require a priori setting of their
values. Due to the unknown of the ground-truth images, the evaluation ofdocument binarization
techniques is subjective and employs human observers for the estimation of the appropriate
parameter values. The selection of the appropriate values for these parameters
is crucial and influences to the final binarization results. However, there is
no predetermined set of parameters that guarantees optimal binarization for all
document images. Thus, the parameter values must be adjusted to correspond to
some of the document image types. This paper proposes a new technique that
allows the estimation of proper parameters values for each one of the document binarization
techniques. The proposed approach is based on a statistical performance analysis
of a set of binarization results, which are obtained by applying various
binarization techniques with different parameter values. The proposed statistical
performance analysis can also depicts the best document binarization result obtained
by a set of document binarization techniques. Based on several experimental
results, we verify (i) the applicability of the proposed evaluation technique
to different types of document images, and (ii) the strong association between user
preferences and statistically estimated values.