I open-sourced a GStreamer plugin suite for KLV metadata workflows

I recently open-sourced a GStreamer plugin suite for practical KLV metadata workflows in MPEG-TS pipelines:

Repository:

https://github.com/mkassimi98/gstklvplugin

Below is a screenshot of the plugin suite in action:

The project is aimed at real metadata transport workflows where KLV is not handled as an isolated payload, but as part of a complete pipeline involving generation, decoding, synchronization with video, and MPEG-TS signaling.

What the project includes

The current plugin suite provides four main elements:

• klvmetaenc: converts JSON into meta/x-klv
• klvmetadec: converts meta/x-klv back into JSON
• klvframeinject: injects KLV metadata in sync with H.264 / H.265 video frames
• tspmtrewrite: rewrites MPEG-TS PMT tables for KLVA metadata signaling

Technical scope

The implementation is oriented to workflows related to:

• SMPTE ST 336 KLV
• MISB ST 0601.8 UAS Datalink Local Set
• STANAG 4609 style transport pipelines
• MPEG-TS metadata signaling aligned with MISB ST 1402 workflows

Why I built it

In many practical systems, metadata handling does not stop at parsing or serializing a payload. It also needs to be transported correctly, synchronized with video, and integrated in a way that is usable in real pipelines.

The goal of this project was to provide a modular GStreamer-oriented solution that covers that full path, from metadata generation and decoding to frame-synchronous injection and transport-stream signaling.

Tooling and repository contents

The repository includes more than just the plugin implementation. It also provides:

• Meson as the recommended build system
• CMake support as an alternative build path
• Python and C++ examples
• local roundtrip examples
• UDP and SRT workflow examples
• automated tests
• Docker support
• installation and packaging documentation
• design notes and implementation details

Current elements

The currently available elements are:

• klvmetaenc
• klvmetadec
• klvframeinject
• tspmtrewrite

Typical use cases

This plugin suite can be useful in scenarios such as:

• video pipelines carrying synchronized metadata
• MPEG-TS workflows requiring embedded KLV
• ISR/UAS style metadata transport
• experimentation with GStreamer metadata integration
• interoperability testing with downstream systems and external analyzers

Open-source repository

You can find the project here:

https://github.com/mkassimi98/gstklvplugin

I also shared a short overview on LinkedIn:

https://www.linkedin.com/posts/mouhsine-kassimi-farhaoui-983738163_opensource-gstreamer-klv-activity-7441931945174978560-mxpJ

Feedback welcome

Feedback is very welcome, especially regarding:

• element and API design
• caps and negotiation choices
• MPEG-TS metadata signaling approach
• interoperability expectations
• general improvements for robustness and maintainability

If you are working on GStreamer, KLV, MPEG-TS, or metadata transport workflows, I would be glad to hear your thoughts.