Multi-Service AV Synchronisation

Executive Summary

• Bridge Technologies introduced a multi-service AV sync comparison feature for the VB440 production probe, focused on frame-accurate synchronisation assessment across multiple delivery paths of the same service.
• The workflow includes placing multiple incoming services onto a shared timeline, selecting a reference, and comparing other paths against that reference to quantify alignment differences.
• The AV Sync Generator feature embeds machine-readable electronic markers into audio and video signals to support real-time, frame-accurate alignment assessment.
• Added APIs expose frame-accurate data from the probe to support user-built automation tools for alignment tasks.

Key Industry Developments

• VB440 multi-service comparison on a shared timeline
• Bridge Technologies announced an enhancement to the AV Sync function in the VB440 production probe, adding multi-service comparison for the same service carried over multiple delivery paths.
• The feature supports frame-accurate synchronisation assessment by allowing engineers to place multiple incoming services onto a shared timeline and compare them against a chosen reference.
• Marker-based, real-time alignment measurement
• The AV Sync Generator feature embeds machine-readable electronic markers into audio and video signals, enabling real-time assessment of frame-accurate alignment between audio and video.
• This marker approach is positioned as a direct measurement method for alignment, using embedded identifiers rather than relying only on indirect timing inference.
• Expanded synchronisation scope beyond audio/video
• The AV sync capability was expanded to include ancillary data synchronisation, along with visualisation of delta between video, audio, and metadata.
• The delta visualisation includes metadata and immersive audio, extending the comparison beyond conventional audio/video pairing.
• APIs for automation using frame-accurate data
• APIs were added so users can develop automation tools that use frame-accurate data from the probe.
• This enables integration of synchronisation measurements into external workflows that can perform alignment actions based on the probe’s frame-accurate outputs.

Real-World Use Cases

• Comparing redundant delivery paths for the same service
• Engineers can assess and compare multiple flows carrying the same service across different delivery paths by placing each incoming service onto a shared timeline and measuring frame-accurate offsets relative to a reference.
• This supports environments where the same content is delivered via multiple independent paths and needs to be evaluated for alignment consistency.
• Supporting seamless switching between sources
• The feature supports identifying frame-accurate offsets between sources and adjusting delays to align paths, which can help prepare sources for switching without introducing timing discontinuities.
• The comparison against a chosen reference provides a concrete basis for delay correction decisions.
• Real-time AV alignment verification using embedded markers
• The AV Sync Generator’s machine-readable markers enable real-time verification of frame-accurate alignment between audio and video signals.
• This workflow is suited to operational checks where immediate confirmation of alignment is required.
• Visualising delta across video, audio, and metadata
• Users can visualise synchronisation delta between video, audio, and metadata, including immersive audio, to identify where misalignment exists across different signal components.
• The inclusion of ancillary data synchronisation extends the analysis to additional elements carried alongside primary essence.

Why It Matters

• Frame-accurate comparison across multiple paths
• Multi-service comparison provides a method to quantify synchronisation differences across multiple delivery paths of the same service at frame accuracy, using a shared timeline and a selected reference.
• This directly supports operational decisions where multiple versions of the same service must be kept aligned.
• Operational measurement via embedded, machine-readable markers
• Embedding machine-readable electronic markers into audio and video signals provides a concrete mechanism for real-time, frame-accurate alignment assessment.
• Marker-based measurement can be used to validate alignment continuously rather than relying solely on periodic checks.
• Broader synchronisation visibility including metadata and ancillary data
• Expanding synchronisation to include ancillary data and visualising delta between video, audio, and metadata increases visibility into alignment across more of the service payload.
• This can help isolate whether misalignment is confined to audio/video or also affects metadata-associated timing.
• Automation potential through APIs
• APIs enable external automation tools to consume frame-accurate data from the probe and perform alignment-related actions in a controlled workflow.
• This supports integration into engineering toolchains where synchronisation measurement and correction are automated.

Sources

• https://bridgetech.tv/bridge-technologies-introduces-multi-service-av-synchronisation-to-vb440/