MPEG (Motion Picture Experts Group) is a standard used for video compression.
MPEG-1: MPEG-1 standard was introduced in 1993. It has a bit rate of 1.5 Mbps. It is generally used for video recorder type output.
MPEG-2: MPEG-2 standard was introduced in 1995. It has a bit rate of 4 to 6 Mbps. It is generally used for broadcast type output. MPEG-2 output has 3 types of frames:
1) Intracoded frames: Intracoded frames consists of still pictures in encoded JPEG format. In every axis it has a luminance of full resolution and chrominance of half resolution. I frames are useful in fast forwarding and rewinding a video.
2) Predictive frames: Predictive frames are based on the concept of macroblocks. They work on the idea in which there is a difference of a block with the last frame.
3) Bidirectional frames: Bidirectional frames works on the concept of differences with previous and next frame.