CamMark

Abstract

To support the development of any system that includes the generation and evaluation of camcorder copies, as well as to provide a common benchmark for robustness against camcorder copies, we present a tool to simulate digital video re-acquisition using a digital video camera. By resampling each video frame, we simulate the typical artifacts occurring in a camcorder copy: geometric modifications (aspect ratio changes, cropping, perspective and lens distortion), temporal sampling artifacts (due to different frame rates, shutter speeds, rolling shutters, or playback), spatial and color subsampling (rescaling, filtering, Bayer color filter array), and processing steps (automatic gain control, automatic white balance). We also support the simulation of camera movement (e.g., a hand-held camera) and background insertion. Furthermore, we allow for an easy setup and calibration of all the simulated artifacts, using sample/reference pairs of images and videos. Specifically temporal subsampling effects are analyzed in detail to create realistic frame blending artifacts in the simulated copies. We carefully evaluated our entire camcorder simulation system and found that the models we developed describe and match the real artifacts quite well.