The process of correcting errors in data that may have been corrupted
during transmission or in storage. Data transmissions are always subject to corruption due to errors, but in video transmissions, error correction needs to deal with the errors but not retransmit the corrupted data. Video errors are corrected using a process of forward error correction in the encoder or through error concealment techniques in the decoder.
Digital Revolution (Part III) - Error Correction Codes At first, the fact that there existed error correction codes was merely a tour-de-force of pure mathematics. Claude Shannon showed that there existed codes that could correct errors. He did this by showing that certain long random strings used as code words would do the job. However, his ideas could not be put to immediate practical use.