Frames can be grouped into sequences called a group of pictures (GOP). A GOP is an encoding of a sequence of frames that contain all the information that can be completely decoded within that GOP. For all frames within a GOP that reference other frames (such as B-frames and P-frames), the frames so referenced (I-frames and P-frames) are also included within that same GOP.

The types of frames and their location within a GOP can be defined in time (temporal) sequence. The temporal distance of images is the time or number of images between specific types of images in a digital video. M is the distance between successive P-Frames and N is the distance between successive I-Frames. Typical values for MPEG GOP are M equals 3 and N equals 12.

This figure shows how different types of frames can compose a group of pictures (GOP). A GOP can be characterized as the depth of compressed predicted frames (m) as compared to the total number of frames (n). This example shows that a GOP starts within an intra-frame (I-frame) and that intra-frames typically require the largest number of bytes to represent the image (200 kB in this example). The depth m represents the number of frames that exist between the I-frames and P-frames.