What is MPEG-4 video?
MPEG-4 Video is a video codec (compressor and decompressor) standard. A video codec is designed to compress and uncompress digital video in order to reduce the amount of bandwidth required to transmit and store the video. This is needed as the raw data rate of uncompressed CCIR601 active digital video*2 is in excess of 158Mbps – over 300 times the capacity a 512kbps ADSL connection and only just over one hour recording on a 80GB hard disk. Simply scaling the video, to SIF*3 resolution, and compressing with standard utilities such as WinZip or gzip could achieve 10:1 compression. However, at least 300:1 compression is needed to stream live video over an ADSL connection and to achieve 300 hours recording to a 80GB hard disk. This level of compression can be achieved with MPEG-4. MPEG-4 is a lossy codec. This means that the compression and decompression does not reproduce exactly the same as the original video but achieves the high compression ratios required at the expense of some qualit
