Updated April 10, 2017. In grammar, a demonstrative is a determiner or a pronoun that points to a particular noun or to the noun it replaces. There are four demonstratives in English: the near demonstratives this and these, and the far demonstratives that and those. This and that are singular; these and those are plural.
In the context of video compression, codec is a concatenation of encoder and decoderâa device that only compresses is typically called an encoder, and one that only decompresses is a decoder. The compressed data format usually conforms to a standard video compression specification.
A digital audio or video file consists of a container holding source data which has been processed through a codec. A codec (coder-decoder, compressor-decompressor, compress-decompress) transforms the analog signal (from a microphone, video camera, etc.) into the ones and zeros of a digital file.