Scalable video coding using inter-layer prediction of spatial intra prediction parameters

Patent metadata

Field	Value
Publication number	US-2016014416-A1
Application number	US-201514666658-A
Country	US
Kind code	A1
Filing date	Mar 24, 2015
Priority date	Oct 1, 2012
Publication date	Jan 14, 2016
Grant date	—

Abstract

The coding efficiency of scalable video coding is increased by substituting missing spatial intra prediction parameter candidates in a spatial neighborhood of a current block of the enhancement layer by use of intra prediction parameters of a co-located block of the base layer signal. By this measure, the coding efficiency for coding the spatial intra prediction parameters is increased due to the improved prediction quality of the set of intra prediction parameters of the enhancement layer, or, more precisely stated, the increased likelihood, that appropriate predictors for the intra prediction parameters for an intra predicted block of the enhancement layer are available thereby increasing the likelihood that the signaling of the intra prediction parameter of the respective enhancement layer block may be performed, on average, with less bits.

First claim

1 . A scalable video decoder configured to
reconstruct a base layer signal from a coded data stream by
block-wise prediction,
a block-wise selection between a spatial intra prediction and a temporal inter-prediction mode, and
using an intra prediction parameter for at least a subset of blocks of the base layer signal for which the spatial intra prediction mode has been selected,
reconstruct an enhancement layer signal from the coded data stream by block-wise prediction, a block-wise selection between a spatial intra prediction and a temporal inter-prediction mode, and using an intra prediction parameter for at least a subset of blocks of the enhancement layer signal for which the spatial intra prediction mode has been selected, comprising
checking a neighboring block of the enhancement layer signal, neighboring a current block of the enhancement layer signal, as to whether same has been predicted using a spatial intra prediction mode;
comprising, depending on the check,
the intra prediction parameter of the neighboring block in a set of probably advantageous intra prediction parameters for the current block, or
the intra prediction parameter of a block of the base layer signal, which is co-located to the current block, in the set of probably advantageous intra prediction parameters for the current block, and

determine the intra prediction parameter for the current block based on a syntax element present in the coded data stream for the current block, and the set of probably advantageous intra prediction parameters.

2 . The scalable video decoder according to claim 1 , configured to perform the check and the check-dependent inclusion with respect to a set of neighboring blocks of the enhancement layer signal, neighboring the current block of the enhancement layer signal.

3 . The scalable video decoder according to claim 1 , configured to comprise in the set of probably advantageous intra prediction parameters for the current block, a default intra prediction parameter.

4 . The scalable video decoder according to claim 1 , configured such that the intra prediction parameter of the neighboring block is comprised in the set of probably advantageous intra prediction parameters for the current block if the neighboring block of the enhancement layer signal has been predicted using a spatial intra prediction mode, and the intra prediction parameter of a block of the base layer signal, which is co-located to the current block, is comprised in the set of probably advantageous intra prediction parameters if the neighboring block of the enhancement layer signal has not been predicted using a spatial intra prediction mode.

5 . The scalable video decoder according to claim 1 , configured to further check whether the intra prediction parameter of the neighboring block fulfills a particular criterion, and perform the inclusion further dependent on the further check.

6 . The scalable video decoder according to claim 5 , configured such that the intra prediction parameter of the neighboring block is comprised in the set of probably advantageous intra prediction parameters for the current block if the neighboring block of the enhancement layer signal has been predicted using a spatial intra prediction mode and the intra prediction parameter of the neighboring block is an angular intra prediction parameter, and the intra prediction parameter of a block of the base layer signal, which is co-located to the current block, is comprised in the set of probably advantageous intra prediction parameters if the neighboring block of the enhancement layer signal has not been predicted using a spatial intra prediction mode or the intra prediction parameter of the neighboring block is not an angular intra prediction parameter.

7 . The scalable video decoder according to claim 1 , configured to even further check whether for the block of the base layer signal, co-located to the current block, the spatial intra prediction mode has been selected.

8 . The scalable video decoder according to claim 1 , configured to even further check whether for the block of the base layer signal, co-located to the current block, the spatial intra prediction mode has been selected and the intra prediction parameter of the block of the base layer signal, co-located to the current block, is an angular intra prediction parameter.

9 . The scalable video decoder according to claim 8 , configured to such that
the intra prediction parameter of the neighboring block is comprised in the set of probably advantageous intra prediction parameters for the current block if the neighboring block of the enhancement layer signal has been predicted using a spatial intra prediction mode and the intra prediction parameter of the neighboring block is an angular intra prediction direction, the intra prediction parameter of the block of the base layer signal, which is co-located to the current block, is comprised in the set of probably advantageous intra prediction parameters if the neighboring block of the enhancement layer signal has not been predicted using a spatial intra prediction mode or the intra prediction parameter of the neighboring block is not an angular intra prediction direction, but for the block of the base layer signal, co-located to the current block, the spatial intra prediction mode has been selected and the intra prediction parameter of the block of the base layer signal, co-located to the current block, is an angular intra prediction parameter, and neither the intra prediction parameter of the neighboring block nor the intra prediction parameter of the block of the base layer signal, which is co-located to the current block, is comprised in the set of probably advantageous intra prediction parameters for the current block if the neighboring block of the enhancement layer signal has not been predicted using a spatial intra prediction mode or the intra prediction parameter of the neighboring block is not an angular intra prediction direction, and for the block of the base layer signal, co-located to the current block, the spatial intra prediction mode has not been selected or the intra prediction parameter of the block of the base layer signal, co-located to the current block, is not an angular intra prediction parameter.

10 . The scalable video decoder according to claim 7 , configured such that a default intra prediction parameter is comprised in the set of probably advantageous intra prediction parameters for the current block if neither the intra prediction parameter of the neighboring block nor the intra prediction parameter for the block of the base layer signal, co-located to the current block, has been selected.

11 . The scalable video decoder according to claim 1 , configured determine the intra prediction parameter for the current block based on the syntax element present in the coded data stream for the current block, by firstly checking, based on the syntax element, as to whether the intra prediction parameter for the current block is a member of the set of probably advantageous intra prediction parameters, and if so, then indexing one of the set of probably advantageous intra prediction parameters using the syntax element, and if not, then deriving another one of a set of possible intra prediction modes, not member of the set of probably advantageous intra prediction parameters, using the syntax element.

12 . The scalable video decoder according to claim 1 , further configured to reconstruct the current block of the of the enhancement layer signal by
forming a weighted average of an inter-layer prediction of the current block acquired from a reconstructed version of the base layer signal, and an enhancement layer

Assignees

• Fraunhofer Ges Forschung

Inventors

• Hinz Tobias
• Lakshman Haricharan
• Stegemann Jan
• Helle Philipp
• Siekmann Mischa
• Suehring Karsten
• Marpe Detlev
• Schwarz Heiko
• Bartnik Christian
• Khairat Abdelhamid Ali Atef Ibrahim
• Kirchhoffer Heiner
• Wiegand Thomas

Classifications

• H04N19/159

  Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction · CPC title

• H04N19/136

  Incoming video signal characteristics or properties · CPC title

• H04N19/187

  the unit being a scalable video layer · CPC title

• H04N19/503

  involving temporal prediction (adaptive coding with adaptive selection between spatial and temporal predictive coding H04N19/107; adaptive coding with adaptive selection among a plurality of temporal predictive coding modes H04N19/109) · CPC title

• H04N19/105

  Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction · CPC title