Open Source Newsletter: NAB2023 Edition

3 min readApr 4, 2023

It’s soon about time for the NAB Show 2023 in Las Vegas and in this edition of the Open Source Newsletter we want to highlight some of Eyevinn’s open source components that will be featured in some of the demos at the show.

WebRTC egress and playback components

In collaboration with DASH Industry Forum and Synamedia in the NAB Future’s Park pavilion on Tuesday April 18th from 1:30 to 6pm, Synamedia will demonstrate a proof-of-concept of the integration of WebRTC signaling into a MPEG-DASH manifest. Featured in this demo are our WHEP-endpoint library, WHEP playback library integrated in dash.js, and our tool for integrating WebRTC/WHEP signaling in MPEG-DASH manifests.

Three novel technologies are introduced in this demo: 1/ The integration of WebRTC signaling into a DASH manifest (following recommendations from the DASH-IF Exploration Group 2022 report) to enable seamless client-side transition from WebRTC to DASH delivery. 2 / The implementation of the WHEP protocol, which is currently discussed at IETF, for a standardized WebRTC client-server signaling. 3/ A server-side adaptive bit-rate WebRTC system that lets the WebRTC gateway switch from one profile to another for clients experiencing variable network performance.

Channel Engine library

While there will be a number of FAST channel technology providers at the show this year and some might already be using the sustainable VOD2Live technology and perhaps even our open source VOD2Live engine library, we believe that a wider adoption of this technology will remove all the redundant transcoding and packaging that consumes unnecessary energy. In addition to the removal of redundant transcoding and packaging VOD2Live give you the benefits:

Real-time transcoding constraints can be avoided
Reduce cost and energy consumption
Provide linear FAST channels to a higher video- and audio-quality
Multiple audio tracks, subtitles and DRM protection

Eyevinn will have a small delegation present at NAB this year if you want to learn more about this technology and how our open source libraries can help you get started. Reach out to sales@eyevinn.se if you want to schedule a meeting.

Channel Engine mosaic

A web application that provides a full screen mosaic (multiview) for channels delivered by a VOD2Live engine based on the open source Eyevinn Channel Engine library.

GitHub: https://github.com/Eyevinn/channel-engine-mosaic

DASH-MPD — A complete MPEG-DASH MPD parser/writer

This MPEG-DASH MPD implementation is meant to include all elements from the MPEG DASH specification (ISO/IEC 23009–1 5'th edition) by starting from the MPD XML schema and auto-generating all data structures. It should also handle namespaces and schemaLocation properly.

It has been enhanced with extra structures from the Common Encryption specification ISO/IEC 23001–7 and proprietary structures and name spaces for some DRM systems.

GitHub: https://github.com/Eyevinn/dash-mpd

Subtitle Generator and API

A microservice to automatically generate subtitles from an input audio or video file using Open AI Whisper.

To start a new transcribe job send a POST request to the /transcribe endpoint with :

{
  "url": "https://example.net/vod-audio_en=128000.aac"
  "language": "en" // ISO 639-1 language code (https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes) (optional)
  "format": "vtt" // Supported formats: json, text, srt, verbose_json, or vtt (optional)
}

The response will look like this where result is the WEBVTT file as a string:

{
    "workerId": "BFabbcCi3IYuWOj6LfsgK",
    "result": "WEBVTT\n\n00:00:00.000 --> 00:00:04.180\nor into transcoding I mean, I could probably add just the keyframe in the start and just\n\n00:00:04.180 --> 00:00:06.920\nskip I-frames and the rest of that.\n\n"
}

Formatted output:

WEBVTT

00:00:00.000 --> 00:00:01.940
So into transcoding, I mean, I could

00:00:01.940 --> 00:00:03.700
probably add just a keyframe in the start

00:00:03.700 --> 00:00:06.700
and then just skip iFrames in the rest of the scenes.

GitHub: https://github.com/Eyevinn/subtitle-generator

That’s all for now, see you in Las Vegas?

Join our community on Slack where you can post any questions regarding any of our open source projects. Eyevinn’s consulting business can also offer you:

Further development of any of these components
Customization and integration of any of these components into your platform
Support and maintenance agreement

Contact sales@eyevinn.se if you are interested.