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GoingGreen

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  1. There's this old clip where she fills it all the way once, then fills it most of the way a second time. Doesn't show the action and the quality isn't too great, but that's what your description reminded me of. Girl Pees in cup while driving.mp4
  2. Many of the earlier and higher end cards did have onboard hardware compression, but later on, TV cards increasingly moved over to software encoding since it made more sense to spend what would have been spent on a hardware encoder on a faster CPU instead. Most of the classic "cx88" cards were of that type. I decided to do a little research on how VHS worked and it turns out that it doesn't just record the composite signal to tape directly, but rather it separates the Y and C signals because the color subcarrier is at too high a frequency to reliably record on standard tape. So to play back a tape, the signal from the tape has to be split into the bands that contain the Y and C signals, decode them, and then recombine into a composite signal. S-video skips the recombine step for a little improvement in quality. https://en.wikipedia.org/wiki/Heterodyne#Analog_videotape_recording Someone really dedicated toward the task of archiving video from VHS could pick off the signal directly from the head amps and process them using a fairly cheap but powerful DSP board like the Red Pitaya, bypassing the 80s/90s decode electronics. It would be quite the challenge to program, however! There's quite a bit of applications for DSP in video archival, even in the purely digital realm. Cross correlation could be used to find duplicate content that's not identical files. Some advanced DSP could theoretically try to figure out if two different files of the same content has one derived from another (and thus inferior due to stacking of compression artifacts) or if they're both encoded from a common master that's no longer available, then possibly try to merge the two to get a better copy in the same way a MIMO radio receiver can get a better signal even if the source is not MIMO.
  3. For PAL/NTSC, those were readily available as PCI analog TV cards. The Linux wikis should have information what chips they use and from there find out how many bits the ADCs are. (And you do want to use Linux for that because good luck finding an analog TV card that works on Windows 10.) Analog TV is long dead so it shouldn't be too difficult to find one of those cards for next to nothing. Use the S-video input if possible, but composite is far more common on VHS decks. For uncompressed HD captures, the hardware is indeed more expensive, albeit still somewhat affordable for the consumer, some are available for about $100. But as far as I'm aware, there are no common consumer storage formats for analog HD video, just some experimental extensions to the VHS format that have never managed widespread use.
  4. As an engineer working with software-defined radio (SDR), doing the color space conversion in analog is no longer the optimum way to do it. Modern ADCs have come a long ways and even one that does 24MS/s at 16 bits - the WM8213 - costs less than $2 in bulk. Doing processing in analog is subject to noise and nonlinearity, plus fast opamps are not cheap. If you're just trying to extract the video off a VHS tape (the most common consumer analog video storage format), it's a moot point when VHS has less than 8 effective bits of signal quality. Capture uncompressed or lossless compressed because disk space is cheap enough to allow that and you don't want compression artifacts between the raw frames and whatever algorithms you try to apply to improve it. I think what has most promise in boosting video quality nowadays is deep learning. An example of that is DLSS, which is used to allow games to render at a lower resolution and then be scaled up in real time for display. An algorithm that does not need to run in real time and can look at future as well as past frames should be capable of even more impressive results.
  5. Not true, it's possible to die from drinking too much. https://en.wikipedia.org/wiki/Water_intoxication
  6. Q: What do you get if you cross a mechanical engineer with a stripper? A:
  7. Can you please make a zip file of the compilation?
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