Restricting EoB NAL Layer IDs for Accurate Inter-Layer Reference Picture Positioning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In multi-layer video coding schemes, End of Bitstream (EoB) Network Access Layer (NAL) units and Reference Picture Sets (RPS) are often dropped or processed incorrectly due to unrestricted layer identifiers, leading to incorrect bitstream decoding and incorrect positioning of inter-layer reference pictures.

Innovation Solution

Restricting the layer identifiers of EoB NAL units to zero and correctly inserting 'no reference picture' entries into the RPS inter-layer subsets based on the view identifier of the current picture to prevent incorrect processing and ensure correct decoding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If layer identifiers of EoB NAL units are unrestricted, then multi-layer coding flexibility is improved, but EoB NAL units are dropped or processed incorrectly leading to decoding errors

Engineering Contradiction:
Improvemulti-layer coding flexibilityVSAvoidbitstream decoding correctness
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent changes the parameter of layer identifier restriction for EoB NAL units. By restricting the layer identifier to a specific value (e.g., base layer identifier), the patent ensures that EoB NAL units are correctly identified and processed during decoding, preventing them from being dropped or misprocessed while maintaining multi-layer coding functionality through proper reference picture set management.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces an intermediary mechanism through the reference picture set (RPS) management. By correctly inserting 'no reference picture' entries into RPS inter-layer subsets based on view identifiers, the patent creates a mediating structure that ensures proper handling of EoB NAL units across different layers, preventing decoding errors while maintaining coding flexibility.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Device complexity

If inter-layer reference pictures are not correctly positioned in RPS, then decoding complexity is reduced, but incorrect bitstream decoding occurs

Engineering Contradiction:
Improvedecoding complexityVSAvoidbitstream decoding correctness
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent applies preliminary action by pre-establishing the correct positioning rules for inter-layer reference pictures in the reference picture set before decoding occurs. By defining clear rules for inserting 'no reference picture' entries based on view identifiers, the patent ensures that reference pictures are correctly positioned in advance, preventing decoding errors without increasing runtime decoding complexity.

Inventive Principle:
Principle #10Preliminary action

3Loss of energy

If EoB NAL units are dropped due to unrestricted layer identifiers, then device resource usage is reduced, but video coding performance deteriorates

Engineering Contradiction:
Improvedevice resource usageVSAvoidvideo coding performance
Core Design Contradiction:
Loss of energyVSProductivity

Solution Approach 1:

The patent enables self-service through proper EoB NAL unit handling. By restricting layer identifiers and implementing correct RPS management, the decoding process automatically and correctly processes EoB NAL units without requiring additional complex control mechanisms or increasing device resource usage, thereby maintaining video coding performance through reliable automatic handling.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP3090544B1Method and device for decoding an inter-layer reference picture set (RPS) in multi-layer decoding
Publication Date: 2021.08.25 QUALCOMM INC
  • EP3090544B1 patent drawingFigure 1A
  • EP3090544B1 patent drawingFigure 1B
  • EP3090544B1 patent drawingFigure 2A

AI summary

Methods for coding an inter-layer reference picture set (RPS) and coding end of bitstream (EoB) network access (NAL) units in multi-layer coding are disclosed. In one aspect, the method includes determining whether a candidate inter-layer reference picture is present in the video information. The video information includes an inter-layer RPS including a plurality of subsets. The method further includes determining an inter-layer RPS subset to which the candidate inter-layer reference picture belongs in response to determining that the candidate inter-layer reference picture is not present, and indicating that no reference picture is present in the inter-layer RPS subset to which the candidate inter-layer reference picture belongs.