The document describes WiSE-MNet, an experimental simulation environment for wireless multimedia sensor networks (WMSNs) developed using the OMNeT++ network simulator. It evaluates existing simulators and chooses to build upon the Castalia WSN simulation model, proposing extensions to support multimedia data types, idealized communication, and new modules for a moving target, camera sensor, and distributed target tracking application. The goal is to enable simulation and testing of algorithms and protocols for WMSNs.