Decoded Picture Buffer Indexing to Reduce Signaling Overhead

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Solution Overview

Problem

Existing video coding techniques incur overhead signaling by indicating which pictures to keep in a reference picture list, even if they are not used for inter prediction, leading to inefficiencies in decoded picture buffer management.

Innovation Solution

Implementing DPB indexing techniques that explicitly signal which pictures can be removed from the decoded picture buffer, reducing the need for marking processes based on reference picture lists and minimizing unnecessary signaling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If pictures are indicated in reference picture lists to be kept for subsequent pictures, then reference picture availability is ensured, but overhead signaling increases

Engineering Contradiction:

Improvereference picture availabilityVSAvoidoverhead signaling

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

Instead of signaling which pictures to keep in reference picture lists, the patent inverts the approach by signaling which pictures to remove from the decoded picture buffer. This is achieved through the dpb_idx syntax element that explicitly identifies pictures for removal, thereby reducing overhead signaling while ensuring reference picture availability through implicit retention of non-signal ed pictures

Inventive Principle:

Principle #13The other way round (Inversion)

2Extent of automation

If a picture marking process is performed based on reference picture lists, then picture management is automated, but device complexity increases

Engineering Contradiction:

Improvepicture management automationVSAvoidmarking process complexity

Core Design Contradiction:

Extent of automationVSDevice complexity

Solution Approach 1:

The patent extracts the picture marking process entirely by directly signaling picture removal indices through dpb_idx. Instead of performing complex marking operations based on reference picture list analysis, the system directly identifies and removes specified pictures from the DPB, significantly simplifying device complexity while maintaining automation through explicit indexing

Inventive Principle:

Principle #2Taking out (Extraction)

3Reliability

If reference picture lists include all pictures to be kept, then reference completeness is maintained, but signaling overhead increases

Engineering Contradiction:

Improvereference completenessVSAvoidsignaling overhead

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

The patent uses indexing copies (dpb_idx) to reference pictures for removal rather than explicitly listing all pictures to be kept. This indirect referencing mechanism maintains reference completeness by implicitly preserving all non-removed pictures while significantly reducing signaling overhead compared to explicit positive listing

Inventive Principle:

Principle #26Copying

Data Source

PatentEP3987777B1Decoded picture buffer indexing

Publication Date: 2025.10.15 QUALCOMM INC

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AI summary

A video decoder is configured to remove pictures from a decoded picture buffer based on the value of an explicitly coded syntax element. A video decoder may be configured to decode a syntax element indicating a picture to remove from a decoded picture buffer, and remove the first picture from the DPB. The video decoder may then decode a current picture, and store the decoded current picture in the DPB.