Closed Caption (CC) support is present on the Cube and other higher level encoder products with SDI video input as of firmware version 7.1.4.
In the encoder's Web UI, select Video Setup, then Device Settings. Under SDI Ancillary Data, choose "Closed Captioning", then click Apply.
Additional details are below:
- when sending direct from a Teradek encoder to the destination, only the MPEG Transport Stream (MPEG-TS) and RTMP streaming protocols will have embedded Closed Caption data
- when sending from a Teradek encoder (e.g. Cube Encoder, Cube Encoder combined with an original Bond, Bond II, Bond Pro, Slice Encoder, or T-RAX Encoder) to a Spunik server in either the standalone or bonded connection modes, all streams sent out by the Sputnik server will have embedded Closed Caption data
Video input: SDI input only
CC type supported: EIA-608 and EIA-708
Insertion method: inserting into H.264 SEI, as per SCTE 128-1
1. Our Decoder products do not have support for outputting Closed Captions as either SDI metadata, or burned in to the displayed video, so you'd need to use either software products (such as VLC media player) or third party hardware decoder products which support the output of Closed Captions.
2. Regarding EIA-608 support:
- Closed Captions formatted to the original 608 standard were inserted into line 21 of an analog NTSC signal. With the introduction of DTV, some manufacturers may have inserted the same caption line into a digital SD-SDI signal. This type of caption is NOT supported on our SDI Encoder products.
- SMPTE 334 defined how to insert 608 captions as a digital ancillary VBI data packet. This VBI data packet is the type of Closed Caption extraction that is possible with our SDI Encoder products.
- EIA-608 Closed Captions are embedded as EIA-708 Closed Captions into the H.264 stream.
3. Our products do not convert / transcode from EIA-708 down to EIA-608 formats.
General Overview of typical close caption workflow
Inserting close captions into a Live SDI stream requires 3 parts
- Captionist (or auto captioning software)
- A Caption Encoder (EEG, Link Electronics, Evertz etc)
- Teradek Cube (SDI Model), Slice, or T-RAX
The Captionist types information into their software which sends either an IP or Serial stream to a caption encoder which then embeds the stream into an ancillary data portion of the SDI stream.
See Wikipedia for more information: https://en.wikipedia.org/wiki/Ancillary_data
Tested Services CDN's with captions
- Wowza and Wowza backed services.