Unlocking Accessibility and Engagement with Wowza’s Flexible AI Captioning
How Wowza is Enabling Intelligent, Real-Time Caption Generation and Delivery Workflows for Live and VOD
The Growing Importance of Captions in Streaming
In today’s global, mobile-first, and accessibility-conscious world, captions and subtitles are no longer a nice-to-have — they’re essential. During our recent webinar, Barry Owen (Chief Solutions Architect) and Ian Zenoni (Chief Engineer) at Wowza took a deep dive into why captioning matters, and more importantly, how Wowza is making it easier and more flexible than ever to implement highly-accurate, reliable captions on your terms.
Understanding Captions vs. Subtitles
Captions expand the reach of your content to global audiences, help meet compliance requirements like WCAG 2.1 AA, and boost engagement even for viewers who can hear — whether they’re watching on mute or multitasking in noisy environments. They also dramatically improve discoverability by enabling deeper video indexing and searchable transcripts.
While often used interchangeably, captions and subtitles serve different purposes:
- Subtitles: Focus on transcribing spoken dialogue, often in multiple languages for foreign viewers.
- Captions: Include dialogue and non-verbal cues like speaker identification, sound effects, and scene descriptions.
Wowza supports both, with complete flexibility to create and deliver them how it suits your needs – whether to serve foreign language audiences, meet accessibility requirements, or to boost engagement on high-value video content.
Why Captions? Compliance, Reach, and Engagement
Barry emphasized several compelling reasons to add captions to your video streams:
- Legal Compliance: WCAG 2.1 AA, Title II (U.S.), and EAA (Europe) all have mandates for live and VOD captions.
- Accessibility: Make content inclusive for the deaf and hard of hearing.
- Global Reach: Translate content for non-native speakers.
- Viewer Preference: Increasingly, viewers prefer watching with captions enabled.
- Discoverability: Captions and transcripts enhance search indexing for VOD.
Wowza’s Flexible Captioning Capabilities
A key consideration to keep in mind with the benefits of captioning is the time and resources needed to generate them. Media organizations today have a diverse technology ecosystem ranging across cloud, on-prem, and hybrid deployments that need to integrate and interface with one another seamlessly. The captioning tool these organizations choose can be a key enabler for more streamlined media operations. That’s why Wowza prioritizes delivering captioning workflow solutions that can be flexibly adapted to any environment: cloud, on-prem, or hybrid.
Similarly, each organization or team will have its own AI strategy and ecosystem, with a preferred Large Language Model (LLM) or AI service for captioning along with any other tools that may be in use. Adopting a “Bring Your Own Model” approach is a must in today’s AI-dominated world to not only enable captions, but deeper AI-powered media workflows like speaker identification, translations, and object detection as well.
Open-Source Caption Handler Plugin for Wowza Streaming Engine
The new open-source WSE Caption Handlers plugin allows developers to generate real-time captions using the provider of their choice, like Azure or Whisper, deployed in the cloud or on-premises.
Key features:
- Generate WebVTT, CEA-608, and CEA-708 captions
- Easily integrate with ASR providers via a flexible plugin framework
- Open-source and extensible, complete customization control without sacrificing accuracy or quality
- “Bring Your Own Model” flexibility to use your preferred provider (e.g., AWS Transcribe, 3Play, Verbit)
Whisper Integration for On-Prem Subtitling
We also released a Whisper Streaming integration, showing how to use OpenAI’s Whisper model to do live speech-to-text conversion — all running locally via Docker.
In a live demo, Ian showed how Whisper can listen to an incoming stream and generate real-time subtitles in a WebVTT format with minimal latency. This is ideal for users who want near-immediate compliance and accessibility with the flexibility to avoid cloud-based services, control costs, or experiment with open-source AI models as they see fit.
Building Modern, AI-Powered Media Workflows
During the webinar, Barry and Ian showcased two demos:
- Azure STT + Translation: They captioned a pre-recorded stream in four languages using Azure’s speech-to-text engine with auto-translation, delivered as WebVTT tracks.
- Whisper Live Captioning: Ian used Docker Compose to run Wowza Streaming Engine and Whisper on a laptop. This demonstrated the high accuracy and sub-second latency using the “tiny” Whisper model, where a WebRTC feed was transcribed live into WebVTT.
These demos prove that whether you’re using a cloud-based API or an open-source local model, Wowza’s tools make real-time captioning practical, reliable, and developer-friendly. By integrating with new modules for Wowza Streaming Engine, you can:
- Add your own ASR engine via the open plugin architecture
- Edit WebVTT files post-stream for better VOD experience
- Choose latency buffers that suit your real-time needs
- Scale up or down depending on budget and accuracy requirements
When coupled with Wowza’s advanced translation and object detection capabilities, this captioning workflow becomes an integral piece of an intelligent media organization. Integrating these tools with one another will empower leaner media operations teams with flexibility, nimbleness, and control to deliver more captivating experiences for audiences of all kinds.
You can try it yourself or reach out to Wowza’s Professional Services for custom implementation or consulting.
Ready for Better Captions?
The world is watching — make sure they can understand, engage, and connect. Whether you’re building a scalable live streaming platform or improving accessibility for an internal webinar, Wowza’s new captioning tools give you everything you need. Additional capabilities, including integrating Whisper with open-source translations to generate multi-language subtitles, are on the horizon.
Check out the GitHub Repos and start building your intelligent captioning workflows today:
Want help integrating this into your media operation? Contact Wowza’s team for a consultation or explore the open-source code to get started.