The HDR-AS15 has a better image stabiliser type than most big sensor size video cameras that were launched around the same time as it. This Sony camcorder has a Digital image stabiliser, whereas most big sensor size video cameras that have been available for a similar time to it have an Optical image stabiliser. Some compact cameras have digital Image stabilisation only, which simply boosts camera sensitivity (ISO) to obtain a faster shutter speeds to help prevent blur. No hardware is involved.
This camcorder's image stabiliser type (Digital) is in fact the worst image stabiliser type across all comparable spec camcorders that came out around the same time as the HDR-AS15.
Across comparable types of camcorder the best image stabiliser type is Optical.