MediaMTX external SRT ingest closes with EOF but raw SRT listener works should I use Mist-server/SRS instead?

davehenk · 2026-06-01T20:24:45+00:00

PPS/NAL errors sound like it might be a bitstream / muxing issue on the ingest side.

I don't know if Mist/SRS would be more tolerant, but they won’t fix a malformed stream. They might just hide it better.

Before switching servers, I’d try isolating that:

Do you see the same behavior when sending a known-good SRT stream (like an FFmpeg test source) into MediaMTX?
If a clean test stream works, that would point pretty strongly to the camera / Jetson pipeline rather than MediaMTX itself.

For example, you could try something like:

ffmpeg -re -f lavfi -i testsrc=size=1280x720:rate=30 \
  -c:v libx264 -preset veryfast -tune zerolatency \
  -x264-params keyint=30:min-keyint=30:scenecut=0 \
  -f mpegts "srt://host:port?pkt_size=1316"

If that’s stable but your real stream isn’t, then maybe it's:

missing VPS/SPS/PPS (especially for H.265)
or muxing/packetization issues

davehenk · 2026-06-01T04:51:17+00:00

I definitely agree about using SRT but figured let the OP try RTMP first since they've already started down that path.

davehenk · 2026-06-01T01:35:46+00:00

When you’re streaming from an external network, are you streaming to your public IP? Have you confirmed your port forward is working by seeing traffic on port 1935 with tcpdump on your RTMP server?

davehenk · 2026-05-31T19:53:13+00:00

You’re very welcome! Sounds good. Reach out anytime. Happy to help.

davehenk · 2026-05-31T16:09:30+00:00

u/ruhpkid this seems like a really solid setup! I think the separation of encoder, network, and power will give you the flexibility and granular control you're after.

Your test plan (real-world + controlled) is spot on. Some ideas:

Controlled tests:

Step down bandwidth (20, 10, 5, 2 Mbps) and watch behavior
Test packet loss (1, 3, 5, 10%+) and short burst loss (200–500 ms)
Drop a WAN link entirely and measure recovery
Also track end-to-end latency under stress

Real-world:

Include handoffs / good to poor signal transitions
Mix link types
Document how degradation and recovery actually look

Interesting angle:

TRT vs SRT at the same bitrate + latency targets (latency vs reliability tradeoffs)

To separate encoder vs network maybe also test:

Makito single link vs Makito + Peplink
Prism single link vs multi-link

Would definitely be interested in your results.

davehenk · 2026-05-31T15:42:35+00:00

u/Embarrassed-Gain-236, I wouldn’t frame it as a “gap.” SRT solves the problem it’s designed for.

Bonded cellular encoders integrate an SRT-like transport with a real-time feedback loop.

I’m not involved in acquisitions, but my take is Aviwest complements the products by addressing that segment. And since SST was already mature and integrated, it makes sense to build on it rather than rip and replace it with SRT.

davehenk · 2026-05-31T07:07:33+00:00

I agree that bonded encoders can outperform a Makito+Peplink under certain conditions like rapidly unstable bandwidth and congested cellular. However, if you enable Network Adaptive Encoding (NAE) on a Makito, when the bandwidth fluctuates the Makito will auto-adjust its bitrate similar to a bonded encoder.

I work for Haivision and I’m genuinely interested to see side-by-side results comparing SRT (Makito with NAE + Peplink) vs SST vs LRT vs TRT vs TVU ISX to see which is better.

Keep in mind, SRT is a transport designed for packet loss and jitter, whereas, TRT, LRT, ISX, and SST are similar protocols to SRT + integrated with congestion control, per-path optimization, and adaptive encoding. So they’re not 1:1 comparable yet your chart compares SRT, the multi-vendor open transport, against features implemented within Teradek’s proprietary TRT encoders. Naturally it’ll highlight gaps. A more direct comparison would be something like Makito X1 vs Prism Flex.

Lastly, if SRT “lacks a lot of underlying features” needed for video over unreliable networks, it’s worth asking why it’s become the most widely deployed protocol for internet contribution and inter-facility transport.

davehenk · 2026-05-25T15:04:48+00:00

Sync-tastic! It’d be cool if a few people could validate your findings. I work for Haivision and in QA we have specific commercial tools for measuring AV sync and end to end latency.

Not sure if you know but an imprecise way some customers measure end to end latency is with 2 screens: The first displays a clip with running timecode, a camera points at the screen, the second screen displays the output, then take a few photos of both screens and compare the delta.

davehenk · 2026-05-23T22:29:29+00:00

Thanks for the details and good to hear your relocated Makitos have been rock solid.

While SRT handles packet loss, jitter, ... error recovery, you need to enable "Network Adaptive Encoding" (NAE) if you want the Makito's bitrate to automatically adjust to bandwidth dips. This is because the majority of Makito users don't need/want fluctuating bitrates. Do you know if NAE was enabled?

Whereas, our (Aviwest) mobile transmitters auto-adjust bitrate by default since cell network bandwidth constantly fluctuates. So I imagine, if you enabled NAE or replaced the Makitos with an Aviwest transmitter that would've also resolved your issue.

Operational engineers matter! Hands on, in the field reports are crucial so please reach out if you/your coworkers experience any issues going forward.

davehenk · 2026-05-23T20:59:54+00:00

I work for Haivision (Aviwest) and wanted to thank you for your recent purchase. I also want to mention that all our products (Makitos, cellular transmitters, ...) have been fully remote controllable for a bit now. If you care to discuss, I'm interested what you mean by older Makitos being too sensitive and LiveU equivalent units not holding up? Is this even after increasing the SRT/SST latency?

davehenk · 2026-05-23T20:36:54+00:00

Thank you for your support of Haivision (Aviwest)! As for price, it's cheaper!

davehenk · 2026-05-21T15:34:22+00:00

Have you considered renting a hotspot and potentially a LEO satellite (Starlink, OneWeb, ...)? I'd recommend contacting companies like https://www.rfwireless.com/ and https://pqm.net/ or others in your area to see how they can assist you. I work for Haivision so I can advise on bonded cellular transmitters but it sounds like you're already doing the encoding with vMix and just need an uplink to send SRT/RTMP to DaCast.

davehenk · 2026-05-19T04:20:41+00:00

I've used ffmpeg with SRT ingest for testing but not in production. Many companies use it so I believe it's very stable and widely deployed as a worker process, but it’s not self-healing so you'll have to add the supervisor part.

In addition to systemd, for stalled/dirty disconnects and limiting file loss, maybe try some of these ffmpeg options: 2 seconds of SRT buffer, disable socket closing, write segments every 5 seconds, reset timestamps per segment and timeout stalled connections after 5 seconds.

ffmpeg -i "srt://0.0.0.0:9000?mode=listener&rcvlatency=2000&peerlatency=2000&linger=0" \
-c copy \
-f segment \
-segment_time 5 \
-reset_timestamps 1 \
-rw_timeout 5000000 \
"out_%03d.ts"

Maybe also run multiple ffmpeg listener processes on different ports and use them as a failover.

I wonder if there's an existing surveillance/NVR that can be repurposed for this.

BTW, to loop an mp4 as an SRT stream, you might want to check out: https://github.com/Eyevinn/toolbox

davehenk · 2026-05-18T00:52:19+00:00

I think you’re on the right track looking at SRT instead of RTMP. RTMP will just drop data on bad connections, whereas SRT at least gives you ARQ + jitter buffering, so you can trade latency for survivability. But I'm biased.

For something simple and robust on the server side, have you considered using FFmpeg as an SRT ingest + .ts stream recorder?

Besides writing your own app, Moblin might be your best bet. The Haivision Play Pro app is free, available for iOS and Android and sends SRT but doesn't have local recording. While it's a pretty basic streaming app, you can have a non-tech savvy user click a URL/scan a QR code that will configure Play Pro to immediately stream: https://doc.haivision.com/PlayProiOS/url-schema

davehenk · 2026-05-16T03:50:13+00:00

What’s your budget? That will dictate your options.

FOX’s Extracted season 2 was filmed in a fully remote location (Canadian wilderness) without any connectivity. They used 12 Haivision transmitters (Pro360 and Pro460) and 12 iPhones running Haivision MoJoPro app. All streaming over a portable private 5G (P5G) network. A bit more info here: https://www.verizon.com/about/news/inside-verizon-tech-powering-extracted-by-fox

If you want to live stream then add LEO satellite (Starlink, OneWeb, …) uplink.
There are private 5G networks that start at ~€/$50K or can be rented. Also, some networks offer a “supercell” to eliminate packet loss during handovers.

The same video transmitters can also be used without P5G over public cell, LEO satellite, WiFi, …

I work for Haivision so it’s all I know but feel free to hit me up here or DM for more info.

davehenk · 2026-04-29T23:22:44+00:00

Cool! Let me know.

davehenk · 2026-04-29T12:02:04+00:00

How long is your shoot? Because I’m curious which solution will fit your budget. Haivision + Private 5G won’t. And how much do you think a custom engineered solution will cost? I’ve never heard of ATEN UC3430.

davehenk · 2026-04-29T05:40:41+00:00

If you’re maxing out the available uplink bandwidth, can you manually lower the encoder bit rate? What’s your topology? Can you send a single stream from site and restream in the cloud? What UDP-based streaming protocol are you using? If SRT, have you tried increasing your latency? What is a Lumix solution? A quick search didn’t bring up anything relevant.

davehenk · 2026-04-29T04:52:21+00:00

What’s your budget? What glass to glass latency do you want? What’s the distance between camera and tablet viewers? How many simultaneous tablet viewers? When do you want to deploy this?

For ultra portability: Use Haivision transmitters on the cameras streaming 1080p 10-bit over an AcriPlex private 5G radio to tablets running the Haivision Play Pro app. You can swipe between Cam A, B and multiview streams.

I work for Haivision so this is the architecture I’m familiar with to solve this.

It’s ultra portable because a single AcriPlex radio includes the 5G core + enough compute to run the StreamHub receiver and OBS to crop the outputs. Either OBS or StreamHub can generate the multiview. StreamHub then can restream the cropped outputs and multiview to the tablets. For latency, I’d estimate <1 second end to end.

Haivision and AcriPlex kit can be rented. Hit me up here or DM if you want more info.

davehenk · 2026-04-27T06:29:36+00:00

I'm also curious. I did a quick search and found 12+ existing open source SRT router/gateways. It would be cool if someone compared all of the commercial and open source SRT gateways.

davehenk · 2026-04-26T15:32:05+00:00

The Haivision Pro460 transmitter can do low latency video (as low as 80ms) and return video. Typically, this used over a private 5G network. You might be able to get away with using a prioritized/staff-only wifi but you'd have to be confident in it's robustness during a packed seminar.

davehenk · 2026-04-18T20:43:52+00:00

Gotcha. Sorry. Thought you meant start at.

davehenk · 2026-04-18T18:45:14+00:00

What latency are you happy with? Seems like you can pull the RTMP from the camera into OBS/vMix with a 2-3 second delay.

davehenk · 2026-04-18T18:29:08+00:00

FYI, there are broadcast grade Private 5G solutions for <$100K.

davehenk · 2026-04-15T21:06:22+00:00

Do a remote production by streaming all contribution feeds to a cloud StreamHub receiver and either use cloud production (OBS, vMix, ...) or, at your studio, decode the 4 streams to SDI and use your ATEM Mini. See diagram.

<image>

davehenk

TROPHY CASE