Intra prediction mode encoding/decoding method and device

Patent metadata

Field	Value
Publication number	US-2018199040-A1
Application number	US-201815913099-A
Country	US
Kind code	A1
Filing date	Mar 6, 2018
Priority date	Jan 30, 2012
Publication date	Jul 12, 2018
Grant date	—

Abstract

An intra prediction mode encoding and decoding method, an image decoding device, and an image encoding device operate by deriving most probable modes (MPMs) from surrounding prediction units adjacent to a current prediction unit and deriving an intra prediction mode of the current prediction unit on the basis of an MPM flag indicating whether an MPM having the same prediction mode as the intra prediction mode of the current prediction unit exists among the derived MPMs.

First claim

What is claimed is:

1 . An image decoding method, with a decoding apparatus, the method comprising:
generating, with the decoding apparatus, an MPM list comprising a plurality of MPMs (Most Probable Modes) for a current prediction unit, wherein the MPMs are derived based on intra prediction modes of neighboring prediction units to the current prediction unit, and the neighboring prediction units comprise a left neighboring prediction unit and an upper neighboring prediction unit, wherein the MPM list comprises three MPMs as candidate intra prediction modes of the current prediction unit, the three MPMs comprising a first MPM, a second MPM and a third MPM, and wherein when the intra prediction modes of the neighboring prediction units are the same, the first MPM is set equal to the intra prediction modes of the neighboring prediction units while the second MPM is set different to the intra prediction modes of the neighboring prediction units; deriving, with the decoding apparatus, an intra prediction mode of the current prediction unit based on the MPM list and an MPM flag indicating whether there is, among the derived MPMs, an MPM having the same prediction mode as the intra prediction mode of the current prediction unit; and performing, with the decoding apparatus, intra prediction on the current prediction unit based on the intra prediction mode of the current prediction unit, wherein in response to the MPM flag indicating that there is, among the derived three MPMs, no MPM having the same prediction mode as the intra prediction mode of the current prediction unit, deriving the intra prediction mode of the current prediction unit comprises:
comparing, with the decoding apparatus, the three MPMs in the MPM list,
rearranging, with the decoding apparatus, the three MPMs based on results of the comparison, the rearranging being performed by changing positions of the three MPMs in an ascending order of mode values;
setting, with the decoding apparatus, a remaining intra prediction mode as a candidate intra prediction mode of the current prediction unit, the remaining intra prediction mode being determined based on remaining intra prediction modes except the derived three MPMs among all intra prediction modes; and
deriving, with the decoding apparatus, the intra prediction mode of the current prediction unit by comparing the candidate intra prediction mode of the current prediction unit with the rearranged MPMs.

Assignees

• Electronics & Telecommunications Res Inst
• Iucf Korea Aerospace Univ

Inventors

• Lee Jin Ho
• Kim Hui Yong
• Lim Sung Chang
• Choi Jin Soo
• Kim Jin Woong
• Kim Jae Gon
• Choi Hae Chul
• Lee Sang Yong

Classifications

• H04N19/11

  among a plurality of spatial predictive coding modes · CPC title

• H04N19/157 Primary

  Assigned coding mode, i.e. the coding mode being predefined or preselected to be further used for selection of another element or parameter · CPC title

• H04N19/593 Primary

  involving spatial prediction techniques · CPC title

• H04N19/70

  characterised by syntax aspects related to video coding, e.g. related to compression standards · CPC title

• H04N19/176

  the region being a block, e.g. a macroblock · CPC title