Incremental validation of digital TV applications in nested context language

This paper presents an incremental validation process for multimedia documents describing interactive digital TV (iTV) applications. This work delves more specifically into documents defined in Nested Context Language (NCL), a declarative language standard adopted by ISDB-Tb and ITU-T for IPTV. The focus of incremental validation, the approach proposed in this work, relies on checking only the pieces of code that have been modified since the latest validation as well as those parts that have suffered any side effects, thus eliminating the need for a thorough checking of the document. The implications of performing this type of validation in a declarative language such as NCL are discussed and implementation details are given. Performance tests comparing the standard and incremental validation approaches have been carried out revealing a significant improvement concerning the latter.