Endec

An endec is a device which acts as both an encoder and a decoder on a signal or data stream, either with the same or separate circuitry or algorithm. The combining of these names is a portmanteau.

Definition

The general difference between an endec and a codec (compressor / decompressor) is that hardware is usually considered to be an endec, while software is considered to be the codec. Similarly, the word "encoding" is usually used for hardware, while "coding" is usually used in regard to software.

A device or program which uses a compression algorithm to create MPEG audio and/or video is often called an encoder, and one which plays back such files is a decoder. However, this is technically a codec, especially if performed in software.^{[citation needed]}

Examples

Examples of encoders, decoders, and endecs include:

• A modem is an endec, likewise a modulator is an encoder and a demodulator is a decoder
• An Emergency Alert System unit is usually an endec, but sometimes just a decoder
• A stereo generator used in broadcasting is an encoder
• A combination ADC and DAC would technically be an endec, though they are usually called CODECs
• Hardware that encodes data bits to a run length limited line code, and decodes the line code back to data bits, is an endec.
• When implementing the Infrared Data Association (IrDA) protocol, often an endec is used between the UART and the optoelectronics.