TBT: Time Base Torture
How good is your time-base corrector, really?
Tired of the mysticism ? Want to check a TBC before purchase?

TBT is an open-source test rig (SW/HW) that tries to answer that with measurements instead of eyeballing a monitor.
An ESP32 (about $5) generates NTSC composite video with precisely controlled faults that can then be captured and graded with an SDO.

It covers the problems a VHS or Betamax deck throws at a TBC:
- line jitter and wow and flutter
- head-switch skew
- dropped and lost fields
- snow and noise bars
- weak burst
- hum

Each fault comes in a ladder from mild to brutal. The signal goes through the TBC under test, and a USB scope captures what comes out. TBT then reports exactly what the TBC fixed, what it passed through, and where it broke.
A full field trial runs about 70 tests in roughly seven minutes and produces an HTML report with a provisional grade out of 100.

Highlights
About 30 tests, about 70 rungs. Going from “how peculiar to “Good God man!). Timing, sync and structure, colour and burst, levels and noise, plus fault tests: how many lost fields in a row a TBC rides through, and a stress-and-recovery hunt for units known to be buggy like black AVTs.

Frame markers in the picture. Every field carries a coded marker. TBT tracks each frame through the TBC and catches dropped, repeated, torn and ghosted frames. Looking for the failure modes that TBCs are known to exibit when dying, or have Chipset defects

Measures the Analog Signal, not just the constructed picture.  When using channel 2 can provide Jitter reporting, and validate what (if anything) the TBC is doing to the signal.

Dying Unit identification . A dropout watch samples the output every second for minutes at a time, allowing for long burn in runs, that can point to failng caps, heat dissipation issues…

Repeatable and comparable. Every fault is deterministic and described in a manifest. Run trials side by side to compare units, or the same unit over time. Saved trials can be re-graded later.

Works with what you have. So long as that’s an ADP2230
Two scope channels give the full picture of TBC performance
With --channels 1, a single channel and a single cable still work..but latency and jitter are going to be based on the model, not the signal.

Find it here: https://github.com/jordancrombie/TBT. The README covers wiring, commands and a sample report. The test catalog is in docs/design.md.

The software was made with the help of AI (100% AI Slop!)
The meat puppet (me) bought the gear, wired it, helped design the test cases.

Also, use the test software at your own discretion. It’s been validated against Datavideo TBC-1000, AVT-8710s all without issue…but it’s in the name…it will put the components under stress.

*Edited to highlight the sloppiness of AI that helped build this!

Has anyone found a good solution for switching cameras on a constellation using DMX? doing a show on disguise at the moment and using an ma3 light for control with companion to switch cameras. Looking for a solution to run everything off of the console just to reduce setup time. I have a mini PC in my disguise rack and was considering building a patch in something like Châtaigne but open to any alternative suggestions!

Thx

Desperately in need of at least 1 UIC for the FSN1400 chassis, who can help me out? Please DM me.

This thing is in active use at a Museum i Volunteer at.

Auction lot for less than 82 usd. Now the fun begins to see if I can get it to work.

I spent 15 years sweating over a CMX keyboard and would sort of like one as a souvenir. Any flavor will do. 300/340/350/3600/omni

Let me know if you see one in a scrap heap somewhere. Struck out on eBay, other than the guy who’s holding out for $500 :(

There's a ton of options out there for generating static test and grid patterns in whatever resolution you want. A popular vibe-coded app these days.

There's a much smaller selection that generate moving video test patterns, but most of them are limited to predefined aspect ratios.

Kards - https://alteka.solutions/kards - lets you generate moving video in custom resolutions, but you cannot export motion to a file, and it's limited in the movement options it gives you.

I'm wondering if there's an existing tool that can:

- Create a variety of moving test patterns in custom resolutions, in particular ones that can stress-test sync across outputs.

- Export as movie files. I want to be able to load these up on to various playback devices, switchers, etc, not be limited to my laptop or other device that might go away after installation.

- Bonus points if it can break up a large canvas into independent videos for each individual output.

I'm rather surprised the existing major players like Pixel Perfect Pro and Vioso don't already have this, unless I'm missing something.

I've been using the Ugreen variants on the mac mini and when I want more video outs I use the Matrox Quadhead2go. The Matrox heats up a bit sometimes and feels unreliable when it blinks a bit and the video disappears for few seconds during a show.

For the sake of reliability I plan to use the Mac studio this time for more outputs and avoid the Matrox. But it still makes me wonder if i need to get a Apple or a Belkin dock which are way more expensive or to keep using the Ugreen till I face any issues.

Is there a more professional approach to this with another device ?

Ran into an issue recently on a live contribution ingest node where network monitoring reported a constant ~25 Mbps bitrate, switch showed 0 dropped frames, NIC reported 0 RX ring overflows, but the ingest receiver was dropping 30-40% of packets per frame burst, killing FEC and video decoding.

Turned out to be the classic micro-burst problem: the encoder was dumping a 400-packet slice back-to-back in an unyielded loop (<150 microseconds). The instantaneous line rate hit ~28 Gbps on the wire.

The default socket receive buffer (SO_RCVBUF=64KB) could only hold ~45-50 packets due to Linux kernel sk_buff slab doubling overhead. The remaining 350+ packets were silently dropped by the kernel (kfree_skb_reason with SKB_DROP_REASON_SOCKET_RCVBUFF_FULL), incrementing RcvbufErrors in /proc/net/snmp without the switch or physical NIC ever seeing a drop.

Built a minimal test harness in Go to isolate the failure mode, measure RFC 3550 inter-arrival jitter, and test two fixes:

1. Application-level leaky-bucket pacing (hybrid sleep + busy-spin down to 41 µs per packet).

2. SO_RCVBUF expansion to 4MB + net.core.rmem_max tuning.

A couple interesting quirks we hit while building the reproduction:

- You can't test this over 127.0.0.1 (loopback) because Linux bypasses veth queue accounting and switches contexts synchronously. Had to use isolated bridge networks / netns.

- Standard time.Sleep() in Go has 50–200 µs of timer slack and sysmon jitter, so pacing required a hybrid sleep + microsecond busy-spin pacer.

Code, Docker Compose reproduction, and /proc/net/snmp telemetry probe are here if anyone wants to run it or test their own ingest tuning:

https://github.com/777nq/jitterbuf

Hello. I am looking for Professional Video Monitors (PVMs), Broadcasting Video Monitors (BVMs) using the CRT technology from the 90s and early 2000s preferably Sony, JVC. I am a retro video gaming enthusiast/collector. So it would be swell if anyone here could give me leads on where I could find those in any condition (working/non-working) etc. I am interested in buying those for restoration and preservation. You guys could DM me too. Thank you. Location:Kathmandu, Nepal.

Panasonic's white paper on their new projector light engine smells like AI to me. 10,000 em dashes. The classic "it's not x it's y." The "why it matters" subject.

Also this feels more like a marketing PDF and less like a white paper to me. Graphs without labeled axes? Were those AI generated too?

If this is AI generated, I am super disappointed in the world. If you can't be bothered to write your own white paper why should I be bothered to read it? May as well get the AI summary from the Adobe PDF viewer.

Hey everyone!

I'm a creative technologist and visual artist looking to connect with people who have more experience in this field and would be open to offering some guidance or mentorship.

My work spans a few different areas, including VJing, projection mapping, lighting design, motion graphics, and interactive installations. I've been experimenting with TouchDesigner, Resolume, DMX lighting, ESP32/LED systems, and hand-tracking technology.

I've been teaching myself a lot of these skills through personal projects and live performances, but I've reached a point where I feel like having guidance from someone more experienced would make a huge difference.

I'm especially interested in learning how professionals approach technical workflows, integrate different systems, develop larger-scale installations, and turn these skills into a sustainable creative career.

I know mentorship is a big ask, so I'm also very open to casual conversations, portfolio feedback, collaborating on projects, or simply connecting with people working in similar spaces.

If anyone has advice on finding mentors in this industry, knows of communities I should join, or would be open to connecting, I'd really appreciate it!

Thanks in advance!

It streams at 1080p at 60 fps, but It was a bit cheaper than some other capture cards.I bought it only to notice that there are basically no drivers anywhere for this thing, and the capture express software isn't detecting it. I found a "driver", but it had viruses from what virus total says... Is there a gen1 driver anywhere for this card, or is this basically e-waste?

Thought it was a live broadcast feed. Til. Thanks!

Got a small company's anniversary event coming up, and during the planning call, the client casually mentioned that their main speaker likes to walk all over the stage. Like, apparently the guy just can't stand still. And... there are only two of us handling cameras and switching.

We got one of those PTZ cameras that can track people on its own, an Obsbot Tail 2. Figured we could just let it follow the guy around while we deal with everything else. Anyone actually using AI tracking PTZs for live events? Would you trust it or still keep someone on manual control?