Audio-Video Synchronization Using Anchor Frames and Audio Levels

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Audio and video signals in multimedia content often experience synchronization issues during recording and transmission due to varying processing and transmission delays, leading to audio lagging behind or ahead of video, which is unpredictable and difficult to correct.

Innovation Solution

A system that identifies synchronization errors by detecting anchor frames coinciding with moments of silence or bursts of high audio levels, using content analyzers to verify temporal alignment and correct discrepancies through delay adjustments based on content type and drift thresholds.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If audio and video signals are transmitted over a network, then multimedia content can be delivered to users, but synchronization errors occur due to varying processing and transmission delays

Engineering Contradiction:
Improvemultimedia content deliveryVSAvoidaudio-video synchronization
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system performs preliminary identification of anchor frames in the video stream and predicts their expected timing positions before actual playback. By establishing expected anchor frame positions in advance and comparing them with actual received positions, the system can detect synchronization drift and apply corrective delay adjustments to realign audio and video streams, resolving the contradiction between efficient content delivery and reliable synchronization

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system continuously monitors the temporal alignment between anchor frames in video and corresponding audio events, detecting drift when discrepancies exceed thresholds. This feedback mechanism triggers automatic delay adjustments to correct synchronization errors, maintaining reliable audio-video synchronization while allowing flexible network transmission

Inventive Principle:
Principle #23Feedback

2Measurement precision

If anchor frames are used to detect scene changes, then synchronization errors can be identified, but false detections may occur when anchor frames coincide with silence or high audio levels

Engineering Contradiction:
Improvescene change detectionVSAvoidsynchronization error detection
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The system introduces an intermediary verification mechanism that checks whether anchor frame detections coincide with audio events such as silence periods or high audio level bursts. By using audio characteristics as an intermediary indicator, the system can distinguish true scene changes from false anchor frame positions, improving both measurement precision and reliability of synchronization error detection

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system replaces reliance on video-only anchor frame detection with a combined approach that incorporates audio signal characteristics. By substituting pure visual analysis with multi-sensory verification using audio cues, the system reduces false detections and improves the reliability of synchronization error identification

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If delay adjustments are applied to correct synchronization errors, then audio-video alignment is improved, but processing complexity increases

Engineering Contradiction:
Improveaudio-video synchronizationVSAvoidprocessing system
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system applies delay adjustments locally at specific anchor frame positions rather than uniformly across the entire media stream. By identifying precise synchronization drift locations through anchor frame analysis and applying corrections only where needed, the system maintains audio-video synchronization reliability while minimizing overall processing complexity

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The system dynamically adjusts delay parameters based on detected synchronization drift thresholds and anchor frame positions. By changing delay values adaptively rather than using fixed adjustments, the system achieves reliable synchronization with simpler processing logic that responds only to actual synchronization needs

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS12432411B2Audio video synchronization
Publication Date: 2025.09.30 COMCAST CABLE COMM LLC
  • US12432411B2 patent drawing
  • US12432411B2 patent drawing
  • US12432411B2 patent drawing

AI summary

Systems, methods, and apparatuses are described for detecting synchronization errors between audio and video signals. Scene changes may be detected based on anchor frames. Offsets between a scene change in a video signal and a reduced audio level or burst of high audio level in the audio signal may indicate a synchronization error.