Apparatus and method for producing a data stream and apparatus and method for reading a data stream

US7433825B1 · kind B1 · utility

Assignee

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Ralph Sperschneider · Erlangen, DE
• Martin Dietz · Nuremberg, DE
• Daniel Homm · Nuremberg, DE
• Reinhold Böhm · Nuremberg, DE

Key dates

• Filing date: Jan 17, 2000
• Grant date: Oct 7, 2008
• Expiry date: Jan 17, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03M7/40
• WIPO field: Basic communication processes
• WIPO sector: Electrical engineering

Abstract

An entropy encoder includes an apparatus for producing a data stream which comprises two reference points, of code words of variable lengths, the apparatus comprising a first device for writing at least a part of a code word into the data stream in a first direction of writing, starting from a first reference point, and a second device for writing at least a part of a code word into the data stream in a second direction of writing, which is opposite to the first direction of writing, starting from the other reference point. In particular, when a raster having a plurality of segments is used to write the code words of variable lengths into the data stream, the number of the code words which can be written starting at raster points is doubled, in the best case, such that the data stream of code words of variable lengths is robust toward a propagation of sequence errors.