Lumens VC-A61P SRT setup: send SRT to Callaba Gateway
More live video workflow notes and product updates.
Written by Iurii Pakholkov
Founder of Callaba. Building cloud video tools for SRT, RTMP, WebRTC, NDI, live routing, monitoring, recording, and production workflows.
Release: Callaba 8.4
For a Lumens VC-A61P SRT setup, use the camera at the venue as the SRT sender and make Callaba the cloud SRT receiver. Use this setup when VC-A61P is at the venue and Callaba is the cloud SRT receiver for monitoring, recording, routing, multiview, or restreaming. Lumens documents SRT, RTMP/RTMPS, RTSP, MPEG-TS, H.264, HEVC/H.265, AAC, and G.711 for this exact model, but I would still confirm firmware and visible SRT fields before the event.
Quick answer
To use Lumens VC-A61P with SRT, set VC-A61P as the SRT Caller and send the stream to a cloud SRT Listener. In this guide, Callaba works as the SRT gateway, receiver, monitor, recorder, and routing layer. Public Lumens material confirms SRT and Stream ID, but does not clearly confirm passphrase or exact caller/listener menu labels, so verify the installed firmware and the visible SRT settings.
The Lumens VC-A61P sends one SRT contribution feed into Callaba. After ingest, Callaba can preview, record, route, restream, and feed multiview in parallel; these are not mandatory sequential steps.
- Lumens VC-A61PSRT sender at venue
- Callaba GatewayCloud SRT listener
- Preview
- Record
- Route
- Restream
- Multiview
What this setup does
This workflow takes the VC-A61P IP stream directly into Callaba over SRT. Callaba is not a PTZ controller in this article; it is the receive, monitoring, recording, routing, multiview, and restreaming layer after the camera contribution feed arrives.
The practical design is simple: the venue network allows outbound UDP from the camera side, Callaba listens in the cloud, and operators watch the received bitrate, packet loss, retransmits, preview, and audio meters before using the feed downstream.
What this model can and cannot do in this workflow
- Lumens lists SRT, RTMP, RTMPS, RTSP, and MPEG-TS for the VC-A61P IP workflow.
- The current product information lists HEVC/H.265 IP streaming up to 4K 59.94 fps and H.264 up to 1080p 59.94 fps, plus a 640x360 stream.
- Audio codecs listed for IP streaming are AAC and G.711. The camera has a 3.5 mm Line In/Mic In audio input.
- Physical outputs include HDMI, 3G-SDI, and Ethernet/IP streaming. The camera also supports PoE+ and RS-232/RS-422 control connections.
- Firmware notes for VC-A61P add important production details, including SRT Stream ID and domain name URL support, RTMP account/password support, and 4K 60/50 fps resolution in later firmware.
- I did not find an official VC-A61P field confirming SRT passphrase/encryption control or exact caller/listener/rendezvous mode labels. Confirm those on the installed unit before relying on them.
- Do not plan VC-A61P as a native NDI source. Lumens documents NDI workflows for the VC-A61PN variant, not for this exact VC-A61P model.
- No separate HEVC license or 4K add-on requirement was identified in the VC-A61P material I used; still confirm firmware before using 4K60 or HEVC in production.
Recommended workflow
Use direct SRT first. In normal cloud contribution, the VC-A61P is the venue-side sender and Callaba is the public SRT listener/server. This avoids asking the venue to accept inbound internet traffic to the camera.
If the installed firmware does not expose the expected SRT settings, update the camera first. If SRT still cannot be used, the next confirmed direct path is RTMPS or RTMP into a compatible destination. Use RTSP through a bridge only when you deliberately want a local pull-and-forward design. Do not use an NDI bridge for VC-A61P unless the hardware is actually the VC-A61PN variant.
When not to use this setup
- If the camera and switcher are on the same production LAN, HDMI or 3G-SDI may be simpler and lower latency.
- If the only destination is a public platform and you do not need cloud monitoring, routing, recording, or multiview, RTMPS may be enough.
- If your production requires native NDI from the camera, use the NDI-marked VC-A61PN workflow instead of assuming VC-A61P has NDI.
- If encrypted SRT is mandatory, confirm that your VC-A61P firmware exposes a passphrase/encryption field before committing to this camera path.
Before you start
- Update or check VC-A61P firmware, especially for Stream ID, domain URL, RTMPS behavior, and 4K60/50 support.
- Decide the UDP port Callaba will listen on and confirm the venue allows outbound UDP to that address and port.
- Decide whether Stream ID is required. Treat Stream ID as case-sensitive and whitespace-sensitive; a copied newline can break the handshake.
- For the first internet test, start with H.264 1080p30 around 4-6 Mb/s, then raise resolution, bitrate, or HEVC only after the path is stable.
- If SRT handshake failures are hard to diagnose, ask Lumens support or check firmware notes for the device-side SRT implementation version, and compare it with Callaba server build/support information.
Create the Callaba ingest
- In Callaba, create an SRT server/listener for this camera feed.
- Choose the public UDP port and note the Callaba hostname or IP address.
- If your workflow requires Stream ID, define the exact value and copy it carefully.
- Use passphrase/encryption only if the VC-A61P firmware exposes a matching field. For the first test, leaving encryption off is often the cleanest way to verify basic transport.
Configure the VC-A61P
- Open the VC-A61P web interface and go to the streaming or network streaming area.
- Enable SRT and enter the Callaba listener address and UDP port according to the fields exposed by your firmware.
- Set the SRT delay/latency field conservatively for the first internet test, then tune after checking RTT, packet loss, and retransmits in Callaba.
- Enter Stream ID only if your Callaba listener requires it. Match capitalization and remove trailing spaces.
- Start with H.264 and AAC for broad monitoring compatibility. Move to HEVC/H.265 or 4K only after confirming downstream decoder/player support.
Settings table
| Where | What to do / field to fill | First-test value | Why / check |
|---|---|---|---|
| Callaba | Create SRT server and choose UDP port | Use a known open UDP port | Callaba should show the listener waiting for a connection. |
| Callaba | Stream ID setting, if required | Simple exact string for the first test | Must match the camera value exactly. |
| Callaba | Passphrase/encryption | Off unless the camera exposes a matching field | A mismatch can prevent the SRT handshake. |
| VC-A61P | SRT Enable | On | Confirmed SRT setting area in the manual. |
| VC-A61P | SRT Port | Callaba UDP port | The camera must target the same listener port. |
| VC-A61P | SRT Delay / latency field | 250-500 ms | Raise it if retransmits or packet loss are visible. |
| VC-A61P | SRT Stream ID | Exact Callaba value, if used | Supported by VC-A61P firmware notes; whitespace matters. |
| VC-A61P | Video and audio encoding | H.264 1080p30 plus AAC | Good first test before HEVC, 4K, or higher frame rates. |
Monitoring
When the stream connects, do not stop at a preview frame. In Callaba, check incoming bitrate, connection uptime, RTT, packet loss, retransmits, codec, resolution, frame rate, preview, and audio meters. On the camera side, confirm that the web interface still shows the intended encoder settings and that local HDMI or SDI output looks correct if you are using it for confidence monitoring.
Failover and local ingest options
For production events, plan what happens if the main encoder, venue uplink, or primary contribution path fails. Callaba can be part of that continuity plan without changing the basic Lumens VC-A61P ingest workflow.
Recording and playback
Recording, web playback, restreaming, and routing are parallel downstream uses after the SRT ingest is stable. If you record or play back HEVC/H.265 or 4K, confirm that the downstream player, decoder, browser path, or production system supports that codec and resolution. For mixed destinations, H.264 is usually the safer first pass.
Troubleshooting
| Symptom | Check in Callaba | Check on device | Likely fix |
|---|---|---|---|
| No connection | Listener is running on the expected UDP port. | SRT is enabled and the port/address are correct. | Allow outbound UDP, correct the destination, or update firmware if SRT settings are missing. |
| Connects then drops | RTT, packet loss, retransmits, uptime. | SRT delay/latency and uplink stability. | Increase latency, lower bitrate, or improve the venue uplink. |
| Stream ID rejected | Expected Stream ID value. | Camera Stream ID field. | Remove trailing spaces/newlines and match capitalization exactly. |
| Handshake fails with security enabled | Passphrase and encryption state. | Whether VC-A61P exposes a passphrase field. | Use matching values only when both sides expose them; otherwise test without encryption first. |
| Video but no audio | Audio meters and detected audio codec. | Line/Mic input, audio level, AAC/G.711 selection. | Enable the correct input and start with AAC if available. |
| 4K or HEVC does not play everywhere | Detected codec/resolution and player behavior. | Firmware level and encoder settings. | Confirm 4K60/50 firmware support, then test H.264 1080p as a baseline. |
Official references
Vendor references
- Lumens VC-A61P product page
- Lumens VC-A61P / VC-A61PN user manual
- Lumens VC-A61P firmware release note
Protocol references
Callaba resources
FAQ
Does Lumens VC-A61P support SRT to Callaba?
Yes. Lumens lists SRT for the VC-A61P, and firmware notes add Stream ID support. Confirm installed firmware and the visible SRT menu before production.
Is VC-A61P an SRT Caller or Listener?
For cloud contribution, use the camera as the venue-side sender and Callaba as the SRT listener. Public VC-A61P material I found does not clearly name caller/listener/rendezvous menu labels, so follow the labels exposed by your firmware.
Does VC-A61P support SRT Stream ID?
Yes, Lumens VC-A61P firmware notes list SRT Stream ID support. Treat the value as case-sensitive and whitespace-sensitive on both sides.
Can I use a VC-A61P SRT passphrase?
Do not assume it. I did not find an official VC-A61P passphrase/encryption field in the material used for this guide. Use it only if your installed firmware exposes a matching field and you have tested it with Callaba.
Can I use NDI from the VC-A61P?
No. Do not plan VC-A61P as a native NDI source. Lumens documents NDI workflows for the VC-A61PN variant.
What should I use if the SRT menu is missing?
Update firmware first. If SRT still is not available, use confirmed RTMPS/RTMP as the direct fallback, or use RTSP through a local bridge when that design is intentional.
Next steps
Build the first test with H.264, AAC, moderate bitrate, and a conservative SRT latency. After Callaba shows stable uptime, clean audio, and low retransmits, raise resolution or move to HEVC if the downstream workflow supports it.
Try Callaba Gateway with Lumens VC-A61P SRT
Create an SRT server in Callaba, send the device feed to the gateway, and check the received stream. After ingest is stable, use Callaba outputs for preview, recording, restreaming, multiview, playback, routing, or API workflows as parallel downstream options.