An encoding error is a mistake which happens during the process of encoding data. Depending on the nature of the mistake, the results of the encoding error are variable. Encoding errors happen for a wide variety of reasons with all sorts of technology, although there are a number of safeguards in place which are designed to minimize or prevent such errors.
In encoding, data is transitioned from one format to another. Encoding is often used to compress data so that it will take up less room, as when a raw audio file is encoded so that it will fit easily on a compact disc. In addition to encoding for storage, data can also be encoded for transmission; that same audio file, for example, might be encoded so that it could be embedded in a livestream from a radio station. Encoding is also used for the purpose of cryptography, a technique which is used to secure data by ensuring that it can only be read with people with the right decoding equipment.
Sometimes an error during encoding occurs because the original data itself is corrupted and the program doing the encoding has difficulty processing it. Errors can also occur when a system's memory is overused during the encoding process, and it is not able to process the encoding smoothly. Likewise, confusing commands issued to a program may disrupt the encoding process, as can events such as power outages. It is also possible for an encoding error to be random in nature, with no apparent cause.
A content encoding error may be fatal. In these cases, the newly encoded content cannot be accessed because of the magnitude of the error. The content may not be recognizable to the program which is supposed to decode it, or the content may be so corrupted as a result of the encoding error that large chunks of data are missing and it is meaningless. For example, am embedded video on a web page may fail to play because of an encoding error.
Encoding errors can also cause glitches, such as skips in a CD, garbled sections of text, or other problems. In these cases the error does not render the content completely unusable. It may pose an obstacle to someone who wishes to access the data nonetheless.
Due to the risks of encoding errors, people usually make sure that the original data is backed up before proceeding with an encoding project. This ensures that if an error does occur, the data is not irreparably lost.