interframe coding

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interframe coding

In video compression, encoding the differences between frames rather than each full frame. Interframe coding often provides substantial compression because in many motion sequences, only a small percentage of the pixels are actually different from one frame to another. However, it depends entirely on the content. A room full of people dancing will compress less than a person sitting in a chair talking.

Also called "temporal compression," interframe coding creates "keyframes" that do contain the entire image. However, in between the keyframes are delta frames, which are encoded with only the incremental differences. Depending on the interframe method, a new keyframe is generated based on either a set number of frames or when a certain percentage of pixels in the material has changed.

Not So Great for Editing
Although compression ratios can be very high with interframe recording, changing the content after it is recorded may yield less than desirable results. For example, in professional broadcasting, the captured video is often edited substantially, and videographers often choose intraframe (in-tra) coding rather than interframe (in-ter) for better results. See intraframe coding.

Inter vs. Intra
Interframe coding stores more frames in the same storage space than does intraframe, but subsequent editing can be problematic. Interframe coding is also called "long GOP" (long group of pictures).
References in periodicals archive ?
BMA provides increased efficiency in interframe compression by identifying the temporal redundancy in the video sequence.
This multiframe compression, known as interframe compression, allows the encoding system to markedly decrease the size of a group of pictures that can range from less than a second to several seconds in length.
It features MPEG-4 interframe compression for high-quality video and increased storage capacity.
264 uses interframe compression to eliminate redundancy between frames, which is why talking-head sequences encode much more easily than World Cup matches.
Interframe compression predicts the contents of a frame based on previous and subsequent I-frames.