SBWDVR H.264 compression delivers the highest quality hardware compression with "lip sync" audio at a very reasonable price. H.264 is MPEG4 Part 10/AVC codec that provides high compression, high quality video, best suited for surveillance application. It makes use of block transfers and motion compensated predictive coding. When compared with MPEG2 coding, MPEG4 ( H264 ) uses 1/3 of the bandwidth (1/3 of storage space) to deliver the same quality video. When compared with MPEG4(ASP), MPEG4 (H264) uses 3/5 of the bandwidth ( 3/5 of storage space) to deliver the same quality video. These cards can be mixed and stacked for more channels. One SBWDVR can support of up to 64 video cameras