Motion vector
Encyclopedia
In video compression, a motion vector is the key element in the motion estimation
process. It is used to represent a macroblock
in a picture based on the position of this macroblock (or a similar one) in another picture, called the reference picture.
The H.264/MPEG-4 AVC
standard defines motion vector as:
Motion estimation
Motion estimation is the process of determining motion vectors that describe the transformation from one 2D image to another; usually from adjacent frames in a video sequence. It is an ill-posed problem as the motion is in three dimensions but the images are a projection of the 3D scene onto a 2D...
process. It is used to represent a macroblock
Macroblock
Macroblock is an image compression component and technique based on discrete cosine transform used on still images and video frames. Macroblocks are usually composed of two or more blocks of pixels. In the JPEG standard macroblocks are called MCU blocks....
in a picture based on the position of this macroblock (or a similar one) in another picture, called the reference picture.
The H.264/MPEG-4 AVC
H.264/MPEG-4 AVC
H.264/MPEG-4 Part 10 or AVC is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video...
standard defines motion vector as:
motion vector: A two-dimensional vector used for inter prediction that provides an offset from the coordinates
in the decoded picture to the coordinates in a reference picture.