alt Hacker NewsNtsc-rs – open-source video emulation of analog TV and VHS artifacts
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Relatedly, I recently made a software decoder for SECAM and PAL: https://github.com/grishka/miscellaneous/tree/master/AVDecod...
Though in my case the purpose was to digitize my video tapes and teach myself about DSP.
Idle thought: I don't think I've ever seen one of these TV emulator things implement the situation where the vertical oscillator was slightly wrong and you get the picture slowly looping up the screen.
You're not getting the full experience of analogue telly artifacts until you emulate colour subcarrier phase shift and colour burst detection failure. (-:
And of course PAL and Hanover bars.
I once tried to fully analyze the amazing NTSC emulation used in OpenEmulator. I went down a rabbit hole that involved losing motivation several lessons in to a signal processing class on YouTube, but for those interested, I did at least pull quite a lot of it apart here: https://observablehq.com/@zellyn/apple-ii-ntsc-emulation-ope...
I also ported it to JavaScript (linked from above page)
Could this be used for training AI to do the reverse, i.e., generate high-quality videos from older analog TV and VHS artifacts? Start from high quality videos, use this or a similar library to generate analog/VHS videos that now have the ground truth available, train AI from the data.
Just installed the OpenFX plugin and tested in DaVinci. It runs snappy and looks awesome with tons of control. It can go from subtle to soup. It really starts getting interesting when you automate the params. Appreciate that this is rooted in actual emulation. I'll definitely use this in my edits. Good find!
I'll wait until they do some PAL emulation: take an NTSC source, blurrily upscale it to 576p, apply a crap deinterlacing algorithm to produce a technically progressive image, and some frame blending to get it to 25 fps. Shitorific.
I do love that this is an area of such active development. But I'm curious to see what the artifact simulation crowd thinks of it. I most often encounter them as shaders for emulators and such, but of course this kind of structure degradation of a pristine video is also in high demand these days for video production. Producers want that 90s-camcorder look but crews can't actually use the clunky 90s-camcorder hardware and formats.
I had written a NTSC emulator in C, based on some other equations I had found, although it expects command-line arguments to control many things (such as the phase), and expects a grey scale farbfeld picture as input and produces farbfeld as output, so it is with still pictures rather than videos.
That's nice. I've always been a fan of this effect. I myself was working on something (way simpler) in the past. I was just getting a pixel splitting into three separate values (r,g,b) and plotting them side by side to emulate LED behavior. I end up creating an image that you can use on your website to give the impression of lines - https://github.com/victorqribeiro/oldTerminal (that was the best I was able to do without using canvas, for the web).
Some day I might try it again using modern css
Fantastic! Is there something like this also for the scratch and hiss of old LP vinyl records? And the various types of squeals, crackles and fuzz of old ham radio setups? Never found anything that can really simulate those well.
Greg! I love this!!! Just last night I was trying to rewatch the x-files and was telling Luna that I would need to get a TV filter/shader/overlay thingy to see it the way it was meant to be seen.
You mind reader you
I was immediately reminded of the fake VHS line artifacts for Stranger Things - A Bad Lip Reading[0], which I assume are sort of a bit about the fake film grain things during the opening titles in the Stranger Things show.
Can anyone explain how this is different than shaders in retro arch?
Are there audio emulators out there that simulate VHS compressed warped audio?
this is really good effect, fantastic output. I had VCR as a kid :-) Gonna have a look at it, specially as it is a Rust project. :clap clap: Thanks for posting this.
I wonder if any of this was used to produce Backrooms
It looks quite unusual, I will definitely try it.
That's interesting!
never expected valadaptive to be on front page of HN
Very cool but the number of settings is overwhelming, not even sure what to do.
This is no doubt a useful production tool when one needs to create the visible artifacts of VHS video for some motivated story reason but as someone who worked in the tech side of broadcast video production starting near the end of the analog era and through the transition to digital, I'm not generally a fan of doing so outside those specific contexts.
The reason is that full bandwidth 6 Mhz analog composite or component video could look wonderful. If you ever have the chance to see a 2-inch quad VTR playing a master tape on a broadcast quality monitor pleased do. I suspect you'll be shocked at how good it looks, even to modern eyes. Yes, the absolute resolution is lower, but the magic of those analog broadcast standards was how gracefully they fit so much image into 6 Mhz of bandwidth. Conversely, VHS tape recording was the absolute worst, most compromised form of that. At the time, it was the best that could be done at consumer prices. But no one ever thought it was remotely good quality in any sense other than perhaps "better than nothing", and even that was hardly unanimous.
There's something about full bandwidth broadcast quality analog composite video that can be genuinely aesthetically pleasing, even compared to digital HDTV. Sadly, very few consumers ever got to see it in its pure, unadulterated form. Even live broadcasts, after being sent up a transmitter tower and down an aerial antenna, were a decimated form of the original signal at the head end (although leagues better than VHS). Yes, modern digital IS better in almost all ways, but in a few ways there was, and still is, something uniquely 'good' about that analog head-end video signal. I won't say 'better' because that's an aesthetic and stylistic judgement but definitely 'good'. Whereas, there's literally nothing good about VHS. At no point ever did a 1980s video creator look on their equipment shelf, see a VHS camcorder next to... literally any other camera or recording system, and say "I'll take the VHS today because it's the better tool for this job."
There's one context where I'm a huge proponent of recreating our analog past and that's when viewing 1980s and early 90s computer or game console graphics created to be displayed on 15khz analog composite video displays. That's when analog CRT emulation via GPU pixel shaders should always be used. The square razor sharp, hard-edged pixels of such content as seen on modern digital flat screens is an inaccurate distortion of the past because no one in that past, like the people involved in the creation or consumption of that media, ever saw square pixels like that. The only displays we had then were CRTs and images made for 15 Khz analog CRTs look not only different but much better on the displays they were designed on and for (or a good simulation of those displays).
Great, now I won't be able to trust that old videos aren't AI slop either.
pretty cool!
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To have true VHS effect, I think we should train AI for this, examples from digital videos to record on true VHS tape, on multiples VHS devices then digitalize and calculate difference between original and digitalized from VHS.
Then even we could have filter like: VHS Panasonic, VHS Sony...
This would be very interesting project.
Time to wheel out one of my favorite quotes about the signature of a medium:
"Whatever you now find weird, ugly, uncomfortable and nasty about a new medium will surely become its signature. CD distortion, the jitteriness of digital video, the crap sound of 8-bit - all of these will be cherished and emulated as soon as they can be avoided. It’s the sound of failure: so much modern art is the sound of things going out of control, of a medium pushing to its limits and breaking apart. The distorted guitar sound is the sound of something too loud for the medium supposed to carry it. The blues singer with the cracked voice is the sound of an emotional cry too powerful for the throat that releases it. The excitement of grainy film, of bleached-out black and white, is the excitement of witnessing events too momentous for the medium assigned to record them." - Brian Eno