Abstract: The invention concerns a data encoding/decoding process. In the encoding process, data are converted from a decoded state into an encoded state in which: the data, both in the encoded state and in the decoded state, are in the form of a stream of binary information, by processing the decoded string of data from left to right, its current prefix and the next binary information being considered, a list of binary patterns being registered, in which for each is emphasized the last binary information and the corresponding prefix, a comparison is made between the current prefix of the decoded string and the prefixes of registered patterns. The list of patterns is a set of patterns that do not occur and when a prefix of the decoded string matches with a prefix of a registered pattern, the next binary information of the decoded string is omitted from the decoded stream to make the encoded stream.