Historically, video was stored as an analog signal on magnetic tape. There are complex relationships between the video quality, the amount of data used to represent the video (determined by the bit rate), the complexity of the encoding and decoding algorithms, sensitivity to data losses and errors, ease of editing, random access, and end-to-end delay ( latency).įurther information: Video coding format § History

A consequence of this is that decompressed video has lower quality than the original, uncompressed video because there is insufficient information to accurately reconstruct the original video. The compression is typically lossy, meaning that the compressed video lacks some information present in the original video. The compressed data format usually conforms to a standard video coding format.

In the context of video compression, codec is a portmanteau of encoder and decoder, while a device that only compresses is typically called an encoder, and one that only decompresses is a decoder.

A video codec is software or hardware that compresses and decompresses digital video.

Download codecs video