Wowza Streaming Engine™ media server software can ingest caption data from a variety of in-stream and file-based sources and convert it to the appropriate format for video-on-demand (VOD) and live streams delivered over HLS and RTMP. Wowza Streaming Engine caption support helps U.S. broadcasters to comply with the Twenty-First Century Communications and Video Accessibility Act of 2010 by providing captioning for television programs that are distributed over the Internet.
Note: In Wowza Streaming Engine, closed captioning in MPEG-DASH streams is currently not supported.
Closed captioning for on-demand streamsWowza Streaming Engine can extract 3GPP Timed Text caption data from MP4 files or from companion files that use Timed Text Markup Language (TTML), SubRip Text (SRT), Web Video Text Tracks (WebVTT), or Scenarist Closed Caption (SCC) formats to specify caption data. This caption data can be injected into HLS streams as CEA-608 captions or into RTMP streams as Action Message Format (AMF) onTextData events. For more information, see:
- Configure closed captioning for Wowza Streaming Engine video-on-demand streams
- Specify a closed captioning language for Wowza Streaming Engine video-on-demand streams
- Use external caption files with Wowza Streaming Engine video-on-demand streams
- Closed captioning property reference for Wowza Streaming Engine video-on-demand streams
Closed captioning for live streamsWowza Streaming Engine can ingest instream closed caption information from AMF onTextData events, AMF onCaptionInfo events, or CEA-608 data. The Wowza Streaming Engine Java API enables AMF onTextData events to be injected into RTMP streams. The ingested caption data can also be delivered in HLS steams as CEA-608 captions. For more information, see:
- Configure closed captioning for Wowza Streaming Engine live streams
- Ingest MPEG-TS DVB Teletext data for Wowza Streaming Engine live stream closed captions