Epiphan Pearl-2 SRT setup for Callaba Gateway
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
Epiphan Pearl-2 SRT setup is a direct encoder-to-gateway workflow: Pearl-2 sends an SRT push stream, and the cloud side listens for it. For contribution over the public internet, I normally use Pearl-2 as the SRT Caller and Callaba Gateway as the SRT Listener. Once Callaba receives the feed, the same source can be monitored, recorded, routed, restreamed, or played back without making those steps a forced serial chain.
Quick answer
To use Epiphan Pearl-2 with SRT, set Pearl-2 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.
Pearl-2 sends one SRT contribution feed into Callaba. After ingest, Callaba can preview, record, restream, route, and provide playback as parallel downstream uses, not mandatory sequential setup steps.
- Epiphan Pearl-2SRT Caller, H.264 channel output
- Callaba GatewaySRT Listener and receiver
- Preview
- Record
- Restream
- Route
- Playback
What this setup does
Pearl-2 is a production encoder, recorder, and decoder system. Official Epiphan documentation lists SRT push output, SRT input, RTMP push, RTMPS push, RTSP input/output, full-bandwidth NDI input, NDI|HX input, and unicast NDI output for Pearl-2. For a Pearl-2 SRT gateway workflow, the cleanest path is not an Epiphan cloud relay. Pearl-2 can send SRT directly to Callaba.
Use H.264 for the first test. The Pearl-2 codec page lists H.264 and Motion JPEG for video encoding, with AAC, MP3, and PCM for audio. I would not plan HEVC/H.265 on Pearl-2 unless Epiphan confirms it for your exact unit and firmware.
Recommended workflow
For routed internet contribution, create an SRT Listener in Callaba and configure Pearl-2 SRT push as Caller. This lets the Pearl-2 start an outbound connection to the public Callaba address and UDP port, which is usually easier than opening inbound ports at a venue.
Searches for Pearl-2 SRT receiver or Epiphan Pearl-2 SRT server can mean different things. Pearl-2 can ingest SRT as a decoder/input device, but in this article Callaba is the SRT receiver/server and Pearl-2 is the contribution encoder. If you reverse the roles and make Pearl-2 the listener, the venue side must accept inbound UDP traffic, so you may need a public IP, port forwarding, firewall changes, or a tested NAT traversal plan.
Before you start
- Confirm Pearl-2 firmware and 4K activation if you plan UHD.
- Confirm the Callaba host, UDP port, Stream ID, AES key length, and passphrase.
- Measure uplink bandwidth before selecting bitrate.
Pearl-2 4K has an activation caveat. Epiphan states that 4K features require the 4K feature add-on, with purchase-date and activation details in the Pearl-2 guide. Also avoid HDCP-protected HDMI sources; they are not suitable for this contribution path.
Create the Callaba ingest
In Callaba, create an SRT server and choose Listener mode. Pick a UDP port that is open on the Callaba host, then decide whether to require a Stream ID and passphrase. If the server is behind a cloud firewall or security group, allow inbound UDP on that port.
Keep the Stream ID and passphrase in a plain text note while testing. Both are case-sensitive and whitespace-sensitive. A trailing space, copied newline, or changed capitalization can break the SRT handshake.
Configure Pearl-2
In the Pearl-2 Admin panel, open the channel you want to send, go to Streaming, click New stream, and choose SRT push. Open the stream settings, set Connection mode to Caller, and enter the Callaba Listener address in the URL field using the format srt://host:port. Add the Stream ID if Callaba expects one.
If encryption is enabled, match the Pearl-2 AES key length and Passphrase to the Callaba SRT server. Epiphan documents 128-bit, 192-bit, and 256-bit AES options and a 10 to 79 character SRT passphrase for Pearl-2 SRT streams. Apply the settings, start the stream, and look for a connected state plus incoming bitrate in Callaba.
Settings table
| Where | What to do / field to fill | First-test value | Why / check |
|---|---|---|---|
| Callaba | Create SRT server and choose UDP port | Any open UDP port, for example 10000 | Port must be reachable from Pearl-2. |
| Callaba | Stream ID | pearl2-main | Copy exactly if enabled. |
| Callaba | AES key length | 128 or 256 bit | Must match the sender plan. |
| Callaba | Passphrase | 10 or more characters | Avoid hidden spaces and newlines. |
| Pearl-2 Admin panel, SRT push stream | Connection mode field | Caller | Outbound connection from venue to cloud. |
| Pearl-2 SRT push stream | URL field | srt://callaba-host:10000 | Use the Callaba public host and UDP port. |
| Pearl-2 SRT push stream | Stream ID field | Same as Callaba | Case and whitespace must match. |
| Pearl-2 SRT push stream | Latency field, in milliseconds | 125 ms for lab; 250 to 500 ms for first internet test | Lower only after RTT, packet loss, and retransmits are stable. |
Monitoring
After starting the stream, check Callaba for connection uptime, incoming bitrate, preview video, audio meters, packet loss, RTT, and retransmits. On Pearl-2, confirm the channel is running, the selected inputs are live, audio is assigned to the channel, and the SRT stream status is active.
Recording and playback
Once the SRT ingest is stable, treat recording and playback as parallel downstream uses. You can record the received feed in Callaba while also previewing it, routing it to another destination, or preparing a player output. Do not wait for preview to become perfect before creating a recording job; instead, check the ingest metrics and audio meters first, then enable the downstream outputs you need.
Troubleshooting
| Symptom | Check in Callaba | Check on Pearl-2 | Likely fix |
|---|---|---|---|
| No connection | Listener running, UDP port open, no incoming bitrate | URL field, Caller mode, stream started | Fix host, port, firewall, or cloud security group. |
| Handshake fails | Stream ID, AES key length, passphrase | Stream ID field and Passphrase field | Remove trailing spaces, copied newlines, and capitalization changes. |
| Connects then drops | RTT, packet loss, retransmits, uptime | Latency and recovery bandwidth overhead | Raise latency, lower bitrate, or improve uplink stability. |
| Video but no audio | Preview and audio meters | Channel audio source and codec | Select the correct audio source and use AAC for the first test. |
| NDI fallback overloads LAN | Bridge input bitrate and dropped frames | NDI output count | Remember Pearl-2 NDI output is unicast NDI, not NDI|HX output; reduce receivers or use SRT. |
If SRT interop remains hard to diagnose, compare Pearl-2 firmware and vendor support information with Callaba release notes, server build information, or support details. Public Pearl-2 pages do not publish a specific SRT library version, so SRT major-version and option compatibility may need vendor confirmation.
Official references
Useful reader resources for confirming exact Pearl-2 settings and protocol behavior:
Vendor references
- Epiphan Pearl-2 tech specs
- Pearl-2 SRT caller and listener setup
- Pearl-2 SRT AES encryption and passphrase
- Pearl-2 NDI streaming notes
- Pearl-2 RTMP and RTMPS push setup
- Pearl-2 codec compatibility
- Pearl-2 4K feature notes
Protocol references
Callaba resources
FAQ
Does Pearl-2 support direct SRT to Callaba?
Yes. Epiphan documents Pearl-2 SRT push output and SRT source encoder mode. Use Pearl-2 as Caller and Callaba as Listener for the simplest cloud contribution setup.
Can Pearl-2 be the SRT listener instead?
Yes, Pearl-2 documents Listener mode, but I treat it as an advanced fallback. The Pearl-2 side would need to accept inbound internet traffic, which often means public IP, UDP forwarding, and firewall planning.
Is Callaba the Pearl-2 SRT receiver or SRT server in this workflow?
Yes. In this workflow Callaba is the cloud SRT Listener, receiver, and gateway. Pearl-2 remains the field encoder sending the contribution feed.
Should I use RTMP, RTMPS, RTSP, or NDI instead?
Use SRT for routed contribution when possible. RTMP/RTMPS push is available as a fallback, with RTMPS certificate validation to consider. RTSP announce can work when the server supports it. NDI is mainly a LAN workflow; Pearl-2 outputs unicast NDI, not NDI|HX.
Does Pearl-2 support HEVC/H.265 for this setup?
I would not plan HEVC/H.265 for Pearl-2 SRT contribution unless Epiphan confirms it for your exact unit and firmware. The Pearl-2 codec pages list H.264 and Motion JPEG for video encoding.
What should I test before the event?
Test firmware, 4K activation if needed, SRT role direction, UDP reachability, Stream ID, passphrase, AES key length, latency, bitrate, preview, audio meters, recording, and your required output routes.
Next steps
Build the path in this order: create the Callaba SRT Listener, start Pearl-2 SRT Caller output, confirm incoming bitrate and preview, then add recording, restreaming, playback, or routing. If the first test is unstable, lower bitrate before changing multiple SRT settings at once.
Try Callaba Gateway with Epiphan Pearl-2 SRT setup
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.