The time line for the ISO video coding standards starts with the creation of the MPEG group, commissioned to standardise video and associated audio coding, in 1984. The MPEG1 standard was finalised in the early 90s, and was intended to storage and offline playback digital video applications at bitrates up to 1.5 Mbps. In the mid-90s the MPEG2 standard for digital broadcasting of TV and HDTV quality video sequences at higher bitrates was released. Currently, the MPEG4 standard, providing a framework for integrated visual communications and interactive multimedia is being finalised.
The group has thoroughly specified the syntax of the MPEG bitstreams, leaving the encoder design to the implementors. The MPEG standards have three key parts: Systems, Video and Audio. The systems part concerns the synchronisation and multiplexing of video, audio and auxiliary data. Only the video part will be described in the following paragraphs.