Strange amplitude fluctuation in video signal
Try syncing your scope on the power mains.  If the voltage fluctuation becomes stable, then likely you have interference from an outside electrical source coupling into your circuit.  Fluorescent lighting would be a good candidate.  Try shutting down or moving away from any high power electric motors or other equipment.  Also cover the CCD lens and make sure that you have an electrical problem even with a black scene.  It's possible that you are seeing the optical effects of room lighting variations as captured by the CCD.