Decoder, encoder and method for supporting adaptive dependent quantization of transform coefficient levels

US12108041B2 · kind B2 · utility

Assignee

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

Inventors

• Heiko Schwarz · Panketal, DE
• Soenke Schmidt · Kiel, DE
• Paul HAASE · Berlin, DE
• Phan Hoang Tung NGUYEN · Berlin, DE
• Detlev Marpe · Berlin, DE
• Thomas Wiegand · Berlin, DE

Key dates

• Filing date: Jun 13, 2022
• Grant date: Oct 1, 2024
• Expiry date: Nov 4, 2042

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04N19/91
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

A decoder configured to decode residual levels, and sequentially dequantize the residual levels by selecting a quantizer out of a set of default quantizers depending on a current transition state, and updating the current transition state depending on a current residual level's characteristic obtained by an application of a binary function onto the current residual level, and depending on a quantization mode information contained in the data stream. The current transition state transitions, according to a surjective mapping which depends on the quantization mode information, from a domain of combinations of a set of one or more transition states with the current residual level's characteristic onto the set of one or more transition states, wherein a cardinality of the set of one or more transition states differs depending on the quantization mode information.