PLAYDECK supports Closed Captions (CEA-608 / CEA-708) and Subtitles (ASS / SRT). They look similar on screen, but they behave differently.
- Subtitles always end up burned into the picture.
- Closed Captions can be burned in or passed through in the signal (SDI VANC, or embedded in supported video streams).
For the full from→to matrix (SDI, NDI, UDP/SRT/DVB, RTMP, HLS, recording), start here:
Closed Captions & SCTE — Overview
In this article:
→ Subtitles vs Closed Captions
→ Subtitles (ASS / SRT)
→ Closed Captions sources
→ Burn-in vs Pass-Through
→ Enable CC on inputs and outputs
→ Quick test
→ Related
Subtitles vs Closed Captions
| Subtitles | Closed Captions | |
|---|---|---|
| Typical sources | ASS embedded, external SRT | CC embedded, SCC/MCC/ANC sidecars, SDI VANC, streams, NDI (PLAYDECK loop) |
| On outputs | Always in the picture | Burn-in or pass-through in the signal |
| Styling in PLAYDECK | Font etc. in settings | Preview/burn-in style in settings; position/animation often fixed inside the CC data |
| Same as SCTE? | No | No — SCTE is separate signaling (overview) |
Subtitles (ASS / SRT)
Subtitles can only come from video files and are always burned onto the frames.
- Add the clip to a playlist.
- Right-click the clip and select the subtitle track (disabled by default).
Embedded: shown as ASS Embedded.
External SRT: same base filename as the video (.srt), in the same folder or in a Subs / Subtitles subfolder.
Wherever you send the channel (SDI, NDI, stream, desktop), the subtitle text is already in the image. Adjust font and related options in settings.
PLAYDECK does not include an editor to type new subtitle/CC text into files. Use an external tool if you need to author captions.
Closed Captions sources
From files
Right-click the clip → select the CC track (e.g. CC Embedded).
Also supported as sidecars (same base name, same folder): SCC, MCC, ANC.
When recording with scc_capture / anc_capture, PLAYDECK can write .scc / .anc next to the media file; playback can pick them up again. See the overview recording notes.
From live inputs / streams
PLAYDECK can read, preview, and forward CC with:
- SDI (if the device supports VANC; enable VANC Data on the input)
- Streams with MPEG-2 or H.264 (also MPEG-4 Part 2 in our tests) — UDP, SRT, DVB-compatible, etc., with
embed_cc='true'on the sender - NDI in a PLAYDECK ↔ PLAYDECK loop (many third-party NDI tools do not show CC)
- RTMP to YouTube with
embed_cc='true'(YouTube can display CC)
Not for CC pass-through: HEVC with embed_cc (no usable pass-through in our tests).
Burn-in vs Pass-Through
In settings (Closed Captions):
- Burn-in (default): CC text is rendered onto the channel output frames. Every destination sees the text in the picture (including Desktop Output).
- Pass-Through (always active): CC is not burned into the output picture. PLAYDECK still shows CC in the channel preview. Downstream players/decoders (YouTube, another PLAYDECK, etc.) are responsible for displaying the captions.
Use Desktop Output (window mode) to check whether text is in the picture or only in the preview.
Tip: If you loop a burn-in channel into a second channel that also pass-through-previews CC, you can see double text (pixels + overlay). Switch the first channel to Pass-Through to avoid that.
CC data often includes fixed position and mode (e.g. roll-up / pop-on). PLAYDECK does not restyle that for preview/burn-in beyond its CC display settings.
Enable CC on inputs and outputs
Full matrix: Closed Captions & SCTE — Overview.
SDI input
Enable VANC Data → Enable Closed Captions and SCTE-104 Triggers.
Required to capture CC (and SCTE-104) from SDI. Opt-in because VANC capture adds processing.
SDI / NDI output
With a Closed Captions license, SDI/NDI output is prepared to carry CC when present in the channel pipeline.
Streams + Recordings
In Parameter, add:
embed_cc='true'
Without this, pass-through CC will not be embedded in the outgoing elementary stream (burn-in still works if enabled).
UDP target: use your LAN IP, not 127.0.0.1.
Quick test
- Load a sample clip with embedded CC; select the CC track; loop the block. Confirm CC in the channel preview.
- Enable SDI and/or NDI output; optionally loop SDI/NDI back into an input (VANC on for SDI).
- Add a UDP (or SRT) stream with H.264 and
embed_cc='true'; play that URL on another channel. - Confirm Desktop Output vs preview behaviour.
Sample clip:
https://downloads.playdeck.tv/assets/Sample Video_QTCC.mov
Related
| Article | What you will find |
|---|---|
| Closed Captions & SCTE — Overview | Full matrix, SCTE domains, limits |
| SCTE on SDI | SCTE-104 |
| SCTE-35 to a stream server | SCTE-35, Nimble, HLS cues |
| Recording CC & SCTE | MKV vs TS, sidecars, playback checks |
