WooshCom announced the introduction of a proprietary Advanced Null Packet Filtering algorithm on its CSX-1641 ASI-to-GigE aggregation platform for use in cable TV headends.The algorithm is intended to strip out unnecessary MPEG null packets while generating an MPEG compliant stream. It's designed to reduce null packets down to a user specified data rate, to give the resulting transport stream a constant bit rate (CBR) regardless of whether the underlying content is variable bit rate (VBR) or CBR.Null packet filtering is intended for processing the data that comes from single program transport stream (SPTS) receivers. SPTS receivers produce a trickle of desirable content amidst a deluge of null data. The company says it's not unusual to find only 3.75 Mbps of standard definition video in a 54 Mbps data stream.