The usage of online signatures is more and more common, and it is an important expectation
to be able to identify which signatures are genuine and which are forgeries. To capture
an online signature, we need some special electronic devices. Many of them can capture
the pen movements even when it is slightly lifted. Online signatures practically consist
of a series of data points. Some approaches do not use all captured points, only
some selected ones. This paper studies the relevance of the usage of pen-up points.
For that, we compared three different cases of gap handling. First, the verifier uses
the signatures in their original form as they were acquired, so there is captured
information for the gaps. Besides, this paper studies two preprocessing algorithms,
first, the removal of the gap points, and second, their removal and regeneration.
The experimental results show that the effects of the usage of pen-up points depend
on the quality of the verification systems.