Direct RF capture is the future?
 

Hello all,
I'm sure many of the regulars are well aware of the VHS Decode project (a fork of the LD Decode project related to the BBC Doomesday laser discs, something we had at school if I remember correctly) which is a whole new paradigm on VHS capture.

Essentially, take the RF from the video-head amplifier, dump that to a hard-disk and sort it out in the computer rather than using traditional video hardware. This does allow for software TBC, AGC, chroma alignment etc without recourse to conventional methods, I guess the whole PAL/NTSC/SECAM stuff becomes somewhat irrelevant too.

Also as this for all intents and purposes is a raw analogue of whatever happens to be on the cassette it will generate a 1:1 clone of the videocassette information and settles all arguments of loss, tapes can be archived this way and should (down the line) better techniques appear raw video 'dumps' will be available to work with rather than conventional video files.

I've picked up a handful of compatible cards (!) for about £30 today to have a play with it, and I'll report back my findings. I'm not an especially good programmer but I'm handy enough with the hardware and have plenty of specimen machines that I can draw an RF feed from. Initial reports suggest the cards need the RC network changing to allow full throughput but that shouldn't be an issue. I'll add anything to the project I think might be useful.

Anybody else playing with this, do you think it's the future? I'm just intrigued at the moment, there are some PAL samples around which look very interesting, have a look on YouTube.

Discuss?

RR

Welcome aboard! Always glad to see more people giving it a try.

I suggest grabbing some of the samples attached to posts in the VideoHelp thread I started, so you can play with decoding and get used to the software side of the workflow.

Oln, who maintains the vhs-decode fork, posts here as hodgey.

Oh wow, that's fantastic!

I've got some cards arriving tomorrow, really looking forward to playing with this and seeing if I can help in any way.

It looks like a very interesting project.

Definitely more reason to store my tapes in a cool dry non-humid place, I never know what's around the corner that can potentially improve the current state of the art (just picked up this hobby last year & made use of the good technical advice in this forum & others)

I've cap'd & edited the nice tapes already (that I have at least) with a respectable rig but no frame TBC, but I can scale up to a frame TBC in the future & remaster at least one troublesome tape if I so desire. I really do like the analog VCR look that kiddies are crazy for these days (you can even buy effects plug-ins that add vcr chroma noise to your videos, can you imagine). I'm well aware that tapes can degrade a bit after cap however.

Either this project can lead to another tool in the toolchest or maybe DataVideo can reissue their TBC's with updated chips, who knows what the future holds?! :congrats:

Singmai company made similar thing but proprietary and expensive, Not available yet but they did make a composite capture device to SDI for $800, I asked him if there is any plans for a Y-C card with USB 3.0 but he said no plans so far.

Definitely, at the moment is probably "one for the geeks" (and I haven't experimented yet, might be beyond me) but it's fascinating, I think there's something seriously cool about doing video capture this way.

The "VCR look", I have used it in videos, usually, people use the famous Red Giant plugin (it's quite expensive) and was created from real tape-stock, trouble is most people use it in its default settings - which is a very aggressive and cartoony "VHS look". It's a cultural shorthand, it doesn't especially reflect reality but it gives the impression of "VHS" that people now know. If you take time to dial in the settings it will accurately reflect videotape, however, most people like/know/just want to use the full heavy-weight 'give me everything' default. Some people like it though, and that's a cool tool, and keeps videotape somewhat relevant.

It has the power (as I read it) to strip out tons of expensive hardware and I can't see a reason why even modest hardware and a few cheap mods and a cheap card and off you go. If not dump tapes and see what happens in the future.

Interesting, there is a way to 'cheat' Y-C to SDI and we do use it occasionally here - but that's with a Sony DSR-2000P, we 'pass through' from Panasonic rack-mount S-VHS units via a ForA FA-310P TBC, I'm not convinced by it as a capture method but it is, like all things, another tool in the box. Occasionally we need SDI from VHS and it kinda does a job, sorta, there are better methods than that though for captures for sure as it blats backwards and forwards Analogue -> Digital -> Analogue -> DV so it's a stable but noisy picture in my setup. We have it genlocked to do this from the source otherwise all sorts of bizarre things happen, these machines all really need to be locked together so it's not especially practical unless you have the cash and space. You'll need a ton of cabling too, and using pre-historic broadcast gear doesn't half eat some power too - add the ADVC 1000 into the mix and the whole shebag can draw 500W and it heats the room up. No issue in broadcast but in a modest office, it makes a surprising amount of heat and noise!

//EDIT I've attached an image - This might make people sigh - as I said, it is a hacky method//




On paper (ha) these things aren't hard to design in 2021, making them stable, marketable and of good enough quality is the issue. There must be a market for a good quality Y-C to USB device, and it "should" be a trivial task to design, but people gotta eat as they say.

It's not cheating, The signal carried in SDI is the official standard for analog to video digitizing rec.601 525/625. That's how it was defined and done using D1 3/4 digital tape for storing it (not to be confused with uMatic) when computer was only used for text editing. All PCI and USB capture cards work the same way using the same principal.

What's not standard about analog video capturing is the following terms, DV, 480p, 720p, HDMI, easycrap, capturing mp4 ... just to name few.

I (generally) do DV captures, I'm in PAL land so it's not a terrible way to capture, appreciated with NTSC it's a bit more of an issue. For most of the work I do, DV is fine. :salute: Let's not start that debate though.

The chain posted there doesn't make very good captures, that's all I can say.

Thanks for posting, we have U-Matic machines so I'm quite aware of the difference :congrats: