Challenge
While VAST (Video Ad Serving Template) is widely used to describe how video ads should be delivered — including media files, tracking, and clickthrough URLs — it’s traditionally limited to VOD and player-controlled scenarios. Extending this to live streaming with SGAI introduces new challenges:
- There’s no pre-encoded content: ad breaks must be inserted dynamically in real time.
- Playback must remain seamless, with no interruptions or visible transitions.
- The solution must remain compatible across different platforms, devices, and HLS players.
Process
During the MonteVIDEO Summer Camp 2025, Qualabs created a proof of concept that translated VAST ad responses into structured HLS metadata usable by SGAI workflows. This became the VAST-to-SGAI project, aimed at enabling scalable, server-guided ad logic for live content.
Ian Zenoni from Wowza developed and showcased how Wowza’s plugin architecture allows insertion of EXT-X-DATERANGE tags into HLS playlists. These tags serve as instructions for when and where to play ads, triggered by SCTE-35 signals or custom plugin endpoints.
- When a break is triggered, Wowza inserts an EXT-X-DATERANGE tag that contains ad timing and metadata.
- The client — in this case, hls.js — interprets the tag and dynamically fetches the ad assets defined by the server.
- This process enables SGAI logic without the need to stitch ads into the stream.
Solution
By combining the power of Wowza’s plugin system with the VAST-to-SGAI conversion service, the team delivered a solution that:
- Leverages standard VAST responses for compatibility with existing ad servers.
- Injects HLS interstitial markers using EXT-X-DATERANGE for precise ad timing.
- Uses client-side playback via hls.js to fetch and render the ad, maintaining interactivity and accurate analytics.
- Supports cross-platform playback without the need for stitched streams or pre-roll hacks.
The real value lies in the flexibility: ads are personalized, seamlessly delivered, and tracked accurately — all while using a lightweight server configuration.
Results
The solution was presented at Mile High Video 2025, where Qualabs had its first official booth. The event featured over 10 live demos in collaboration with key partners, including Wowza, Dolby, AMD, and more. This integration was one of the most commented demos, illustrating how live streaming monetization can evolve without sacrificing user experience.
By showing real-time SGAI powered by VAST metadata and Wowza’s architecture, the demo proved the model is not just feasible — it’s production-ready. Viewers saw seamless transitions, while backend systems retained full measurement and targeting capabilities.
You can explore the full list of showcased demos here: mhv2025.qualabs.com/home
