Comment by dylan604 | Hacker News Reader

Comment by dylan604 | Hacker News Reader

I'd love to see an option to have the image pincushion and introduces a buzz in the audio from an video signal that was too strong? That was one of my favorite. Everyone focuses on the interlacing, giant pixels shapes, and the fun with chroma bleed, but some of the most bizarre things could happen when you pushed the analog signal too far. The 1 volt peak-to-peak was a rule for a reason, and going past was possible. Terms like whiter-than-white from pushing the video signal from a test pattern past 100ire on a scope could cause issues with the combined RF modulated audio/video signals. The most flagrant offender was white text. If you were competent at your job, you never used 8-bit 255,255,255 for white. That was out of bounds for NTSC, so 235,235,235 was typical instead for white.

The next filter would be the infamous "broadcast safe" filter that would clamp the video signal to video was not higher than 100ire. Allowing for chroma clamping separate from video clamping would be a bonus. Hell, just give the basic functions of a TBC to the users. They don't need to understand what they are doing to the signal so much as just a few knobs to get creative!

The horrible sound of high frequency CRT screaming meant that I couldn’t go into many electronics areas or stores until the nineties.

Unbearable high frequency noise does tend to fix itself given a few decades or so.

They were referring the fact that CRTs went the way of the dodo, and flat panels replaced them. This high frequency noise was a unique feature of the CRT.

> until the nineties.

CRTs lasted well into the 2000’s. I think the reference is to the fact that one loses the ability to hear CRT whine as one gets older, since the upper frequency limit of human hearing declines with age.

No, it’s more an illustration that I was forgetting when the transition occurred. In reality it was probably 2002 or 2004 before the pain stopped.

glad i was on the same page with you, and not like everyone else making assumptions about your hearing ability!! =)

I suspect contravariant was making a joke that as you get older, your ability to hear high frequencies gets worse. After "a few decades or so" you likely won't be able to hear the flyback transformer squealing at 15 625 Hz any more.

At the end of my day at one of the post houses I was at around this time, I had to ensure all of the monitors were off. I could do it in the dark just by listening for this noise and know if any where on or not. Some of the reference monitors were never turned off though, and I had to ensure they had the correct signal routed to them to avoid burn-in.

I had an Atari ST in the living room and sometimes I would forget to turn the monitor off when I went to bed... but I was always reminded by the high pitch noise I could hear all the way in my bedroom.

Audio buzz emulation has been done already with a Gameboy emulator and from what I could recall when trying it, it was pretty dead-on. I wished I could remember which one it was but indeed, it's a rarity that emulators emulate some of the more esoteric, some might say 'unwanted', faults of the system.

You are probably thinking of SameBoy :)

Also, while the representation of the pixel grid is fairly accurate, it's missing the chromatic aberration from the fact that they were individual electron emitters of red, green, and blue phosphor dots. Pushing the red channel 0.05f and the blue channel -0.05f on the x axis should do the trick.

There's a fun technique in After Effects to separate the image by channels, and then apply an effect turning the image into grids of small circles. Nudge the red a couple of pixels left, the blue a couple of pixels right, and then the green a couple of pixels up. When these are merged back, you get that very look you've described.

Yeah, we can do it in the shader by taking the UV texcoord, sampling the texture rgb, then using a collector, add the r, g, b values to the collector with the offsets in uv's to return the pixel color. It's extremely easy to do in HLSL/GLSL/WGSL/SPIRV/Metal. It can even be controlled using a vector map for the offsets so you can tune it and vignette the chromatic aberration around the edges of the screen. Giving it that truly retro CRT arcade feel. The more the spherical projection, the more aberration.

https://lettier.github.io/3d-game-shaders-for-beginners/chro...

The first time I spoke with a 3D graphics type person that started to talk to me a video engineer type person about UV this UV that, I could not grok their use of the chroma channels needing coordinate position. Just another example of how terms get new definitions depending on the field using them. To this day, my default for UV is chroma related, not projection related, so I sometimes have to re-read something in the right context.

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