Pictures/Frames
While the terms "frame" and "picture" are often used interchangeably, strictly speaking, the term picture is a more general notion, as a picture can be either a frame or a field. A frame is a complete image captured during a known time interval, and a field is the set of odd-numbered or even-numbered scanning lines composing a partial image. When video is sent in interlaced-scan format, each frame is sent as the field of odd-numbered lines followed by the field of even-numbered lines.
Frames that are used as a reference for predicting other frames are referred to as reference frames.
In such designs, the frames that are coded without prediction from other frames are called the I-frames, frames that use prediction from a single reference frame (or a single frame for prediction of each region) are called P-frames, and frames that use a prediction signal that is formed as a (possibly weighted) average of two reference frames are called B-frames.
Read more about this topic: Video Compression Picture Types
Famous quotes containing the words pictures and/or frames:
“And what is the use of a book, thought Alice, without pictures or conversations?”
—Lewis Carroll [Charles Lutwidge Dodgson] (18321898)
“In frames as large as rooms that face all ways
And block the ends of streets with giant loaves,
Screen graves with custard, cover slums with praise
Of motor-oil and cuts of salmon, shine
Perpetually these sharply-pictured groves
Of how life should be.”
—Philip Larkin (19221986)