The Sarnoff Acadia® II is a powerful vision processing SoC (System-on-a-Chip) that was specifically developed to support advanced vision applications where system size, weight and/or power are severely constrained. This paper, targeted at vision system developers, presents a detailed technical overview of the Acadia® II, highlighting its architecture, processing capabilities, memory and peripheral interfaces. All major subsystems will be covered, including: video preprocessing, specialized vision processing cores for multi-spectral image fusion, multi-resolution contrast normalization, noise coring, image warping, and motion estimation. Application processing via the MPCore®, an integrated set of four ARM®11 floating point processors with associated peripheral interfaces is presented in detail. The paper will emphasize the programmability of the Acadia® II, while describing its ability to provide state-of-the-art realtime image processing in a small, power optimized package.