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.
In the mid 20th century, a codec was a hardware device that coded analog signals into digital form using pulse-code modulation (PCM). Late in the century the name was also applied to a class of software for converting between different digital signal formats, including compander functions.n audio codec converts analog audio signals into digital signals for transmission or storage. A receiving device then converts the digital signals back to analog using an audio decompressor, for playback. An example of this is the codecs used in the sound cards of personal computers.