An interactive environment for signal processing on a VAX computer

We have developed a software package, ISPUD, which has proven useful for signal processing. The package is based on the principles of data abstraction and represents signals as high-level data objects. It uses a simple interpreter to provide an easy-to-use, interactive, and extensible processing environment. In contrast to other abstraction-based packages, which require single-user LISP machines, ISPUD runs on a multi-user VAX with graphics terminals.