Arithmetic coding for transforming video and picture data units

US7379608B2 · kind B2 · utility

Assignee

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

Inventors

• Detlev Marpe · Berlin, DE
• Heiko Schwarz · Panketal, DE
• Thomas Wiegand · Berlin, DE

Key dates

• Filing date: Dec 4, 2003
• Grant date: May 27, 2008
• Expiry date: Jun 1, 2026

Classification

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

Abstract

A method for encoding a video frame or picture comprises dividing up the video frame or the picture in portions of a first type associated with a first scanning pattern, and portions of a second type associated with a second scanning pattern. Data corresponding to a predetermined of the portions of the video frame or picture is transformed into a two-dimensional transform coefficient array. Fhe transform coefficients are precoded in order to obtain transform data units. One of a first and a second set of context models is chosen depending on as to whether the predetermined portion is a portion of a type being associated with the first or the second scanning pattern. One context model of the chosen one of the first and the second set of context models is assigned to the transform data unit based on the scanning position assigned to the predetermined transform coefficient. Finally, the transform data unit or a sub-unit thereof is arithmetically encoded into a coded bit stream based on the probability estimation with which the assigned context model is associated.