BD-ROM Graphics Stream Epoch Synchronization

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing recording media and reproduction apparatuses face processing delays and increased complexity when handling high-resolution graphics streams, particularly when multiple display sets are processed sequentially, leading to higher manufacturing costs and hindering widespread use due to the need for dual processor-controller systems.

Innovation Solution

A recording medium is designed to allow the Object Buffer and Graphics Plane to be flushed at the end of a display set by ensuring that the active periods of presentation composition segments in different display sets do not overlap, using time stamps to manage the decoding and presentation of graphics streams, enabling parallel processing without the need for a dual processor-controller system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If each display set is processed sequentially after the preceding display set is completed, then processing simplicity is maintained, but processing delay increases significantly

Engineering Contradiction:

Improveprocessing simplicityVSAvoidprocessing delay

Core Design Contradiction:

Device complexityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by pre-organizing display sets into Epochs with defined boundaries and pre-calculating PTS/DTS relationships. This allows the reproduction apparatus to prepare for parallel processing in advance, enabling multiple display sets to be processed simultaneously without requiring complex real-time coordination, thus reducing processing delay while maintaining reasonable system complexity.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent segments the graphics stream into discrete Epochs, where each Epoch contains one or more display sets with non-overlapping active periods. This segmentation enables independent parallel processing of different Epochs while maintaining processing simplicity within each Epoch, effectively resolving the contradiction between processing simplicity and processing delay.

Inventive Principle:

Principle #1Segmentation

2Productivity

If a dual processor-controller system is used to achieve complete parallel processing of display sets, then processing speed is improved, but device complexity and manufacturing cost increase

Engineering Contradiction:

Improveprocessing speedVSAvoidinternal construction complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent introduces dynamic time stamp management where PTS and DTS values are adjusted based on the Epoch structure and display set boundaries. This dynamic timing control enables a single processor-controller to efficiently manage parallel processing of multiple display sets by coordinating their execution through time-stamp-based scheduling, achieving high processing speed without requiring multiple processors.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the temporal parameters (PTS/DTS relationships) of display sets by organizing them into Epochs with specific boundary conditions. This parameter change allows the system to control the processing flow and enable parallel processing within a single processor-controller framework, improving productivity while avoiding the complexity of dual processor systems.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If active periods of PCS in different display sets overlap, then parallel processing capability is improved, but buffer flushing becomes impossible

Engineering Contradiction:

Improveparallel processing capabilityVSAvoidbuffer flushing capability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies beforehand cushioning by designing the Epoch structure with sufficient time margins between display sets. The PTS/DTS relationships are carefully calculated to ensure that even when display sets are processed in parallel within an Epoch, the buffer has adequate time to flush before the next display set begins, preventing data corruption while maintaining parallel processing capability.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The patent introduces the Epoch structure as an intermediary layer between individual display sets. This intermediary organizes display sets into groups with controlled overlapping active periods, allowing parallel processing within the Epoch while ensuring that buffer flushing requirements are met at Epoch boundaries, thus resolving the contradiction between parallel processing and buffer flushing.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS8126316B2Recording medium, recording method, reproduction apparatus and method, and computer readable program

Publication Date: 2012.02.28 PANASONIC HOLDINGS CORP

AI summary

An AV Clip generated by multiplexing video and graphics streams is recorded on a BD-ROM. PTS(EPOCHm DSlast[PCS]) and DTS(EPOCHm+1 DSfirst[PCS]) satisfy a relation PTS(EPOCHm DSlast[PCS])≦DTS(EPOCHm+1 DSfirst[PCS]), where PTS(EPOCHm DSlast[PCS]) is a presentation time stamp of a packet containing a PCS (Presentation Composition Segment) in a last display set EPOCHm.DSlast, and DTS(EPOCHm+1 DSfirst[PCS]) is a decoding time stamp of a packet containing a PCS in a top display set EPOCHm+1.DSfirst.