This document outlines a set of coding rules for video-oriented use of YAPI, the Y-chart Application Programmer's Interface developed at NatLab for modeling and simulating signal processing applications. These rules, referred to as "Video YAPI" or simply VYA, resulted from a cooperation between the developers of YAPI, whose field of expertise is system design tools, and video algorithm developers at Philips Research Briarcliff. As such, they meet the needs of video algorithm designers that wish to express their algorithms in a unified manner, as well as the needs of system developers wishing to efficiently implement such algorithms using a Y-chart based design flow. VYA compliant software modules are plugable and highly re-usable. The former is by virtue of standardized interfaces for video and control signals; the latter is obtained by a carefully chosen application of YAPI. As a result, a project that develops VYA modules can feed its output efficiently into projects that deal for example with: