Jaakko J. Sauvola

Learn More
A new method is presented for adaptive document image binarization, where the page is considered as a collection of subcomponents such as text, background and picture. The problems caused by noise, illumination and many source type-related degradations are addressed. Two new algorithms are applied to determine a local threshold for each pixel. The(More)
A new method is presented for adaptive document image binarization, where the page is considered as a collection of subcomponents such as text, background and picture. The problems caused by noise, illumination and many source type related degradations are addressed. The algorithm uses document characteristics to determine (su #ace) attributes, ofen used in(More)
While peer-to-peer (P2P) has emerged as a new hot communication concept among the Internet users, mobile usage of P2P applications is still taking its first steps. This article first elaborates the evolutionary process that P2P architectures are going through. Challenges and requirements for mobile P2P are then identified, followed by a definition of a(More)
An infrastructure based on multiple heterogeneous access networks is one of the leading enablers for the emerging pervasive and ubiquitous computing paradigm, in which the optimal management of diverse networking resources is a challenging problem. This paper presents a context-aware policy mechanism and related end-to-end evaluation algorithm for adaptive(More)
Network QoS parameters experience great fluctuations during the execution of network applications. Especially in mobile and pervasive computing environments the variation becomes more serious. Applications need to adapt their functions to the changing network status. Moreover, an enhanced software platform is necessary to provide adaptive network management(More)
The existing skew estimation techniques usually assume that the input image is of high resolution and that the detectable angle range is limited. We present a more generic solution for this task that overcomes these restrictions. Our method is based on determination of the first eigenvector of the data covariance matrix. The solution comprises image(More)
The trends of network convergence and mobile accessibility in the Internet are bringing new challenges to the connectivity management of end hosts. Concerning network convergence, the configuration of heterogeneous access networks should be taken into consideration. As for mobile accessibility, seamless handoff between diverse access points is a challenging(More)
Mobile communication is continuously one of the hottest areas that are developing at a booming speed, with advanced techniques emerging in all the fields of mobile and wireless communications. Current times are just the beginning for deploying 3G mobile communication systems, while research on the next generation of mobile communications, 4G wireless and(More)