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Martin Scorsese should sponsor https://github.com/oyvindln/vhs-decode https://github.com/oyvindln/vhs-decode :-) It's the ultimate in VHS preservation. I'm s

Martin Scorsese should sponsor https://github.com/oyvindln/vhs-decode https://github.com/oyvindln/vhs-decode :-) It's the ultimate in VHS preservation. I'm sure the Venn diagram between HN and Hollywood could make this happen!

kouru225 3y ago
I’m sorry what is this? Is this a software capture card? I’m so confused.
- pdabbadabba 3y ago
  It appears to be software designed to use an SDR or (and?) a DTV capture card to capture the output of a VCR playing a VHS at the RF level, and then transcode and store it. Pretty cool, if I'm understanding it correctly!
  - Solvency 3y ago
    How lossy is transcoding at the RF level of an already lossy medium?
    - actionfromafar 3y ago
      It's much better than any other existing technology to capture VHS. It bypasses all analog processing of the signal by the VHS player and captures the video signal directly from the tape head. All further processing is then done in software. If any improvements in software processing is made, the "raw" capture can then be reprocessed with better results.
      - bitwize 3y ago
        So it's like a Kryoflux for VHS tapes? That is cool.
        actionfromafar 3y ago
        Ha, adding that to my parlance! It's exactly like Kryoflux for VHS tapes. An example - S-VHS tapes can not be played back in regular VHS players. They can't handle the format. But with vhs-decode, it doesn't matter. A regular cheap VHS player can "rip" an S-VHS tape. And decode the HiFi FM-stereo signal, too.
        rainbowzootsuit 3y ago
        Or Domesday Duplicator for LaserDisc Preservation.
        gofixurcode 3y ago
        It’s actually a fork of that project!
      - iisan7 3y ago
        Best at capture/preservation, but only theoretically best at playback someday. Currently the best software processing algorithms are imo not on par with video playback quality from the best hardware of the era, especially for damaged tapes. It's hard, although certainly not impossible, to imagine that changing. I'm 100% glad it exists though.
        actionfromafar 3y ago
        You could always take the best hardware of the era, and capture from that. If you were talking about decks. I'm not sure about playback - the output from vhs-decode looks pretty darn good to me, but I'm not an expert at all in composite video gear.
        iisan7 3y ago
        Right, my language was sloppy but I meant two things-- the quality will still be dependent on the hardware chain, and I should expect that a 'bit perfect' capture of a VHS tape will usually be inferior to one captured from a vintage pro deck. And then regarding processing, I'm not a professional, but I've done several successful restorations using virtualdub and avisynth, and on some degraded tapes I couldn't do nearly as well as whatever magic was going on in the vhs to dvd section of the JVC SR-MV50.
        xattt 3y ago
        Even the best VHS decks from the 80s/90s, which would have been used in production environments and thus “well worn”, would have wear-related quality issues.
        actionfromafar 3y ago
        But that’s the beauty of vhs-decode. The transport mechanism needs to be stable and the head clean. The rest of the player doesn’t matter.
        xattt 3y ago
      - kmoser 3y ago
        Yes, but still don't throw away the original tapes, because if a better (read: more accurate/sensitive) tape head ever becomes available, you'll want to use it to upgrade your capture device and then re-scan the original tapes with even better fidelity.
- pkkm 3y ago
  It's a fully software-based VHS decoder. It takes the raw signal from a VHS tape, captured with a high speed sampling device, and reconstructs the video on your computer. In theory, this approach should allow higher quality digitization than any physical VHS player - it cuts the analog decoding electronics out of the loop, and it allows you to capture once, then tweak the algorithm and decode many times without disturbing the tape. You could even preserve the raw captures in case better decoding algorithms come out in the future.
deleted 3y ago
[deleted]
pkkm 3y ago
I think the biggest obstacle right now is not the software, but the hardware. The software works, but requires either buying a $300-$500 set of three circuit boards, or finding a specific PCIe capture card and potentially modifying it. If someone made a nicer version of the Domesday Duplicator - single board in a case, $100 to $200 - I think that would make the project a lot more accessible. Even better would be if someone started selling modified VHS players, having replaced their normal electronics with a capture device and a USB3 port. After all, many people don't have a soldering iron or a desktop computer.
- actionfromafar 3y ago
  If we are talking about serious archiving of lots of tapes, $500 for a capture device is nothing. The labor costs of keeping the actual tape deck(s) in good order is probably going to dwarf. But I have actually toyed with the idea of setting up complete workstations modified player, and a slightly better software UX. Don't know how to reach the market willing to pay for such things, though. For tinkering at home, the specific PCIe capture device is actually quite easy to find, it seems it's still produced for some reason.

kouru225 3y ago

I’m sorry what is this? Is this a software capture card? I’m so confused.

pdabbadabba 3y ago
It appears to be software designed to use an SDR or (and?) a DTV capture card to capture the output of a VCR playing a VHS at the RF level, and then transcode and store it. Pretty cool, if I'm understanding it correctly!
- Solvency 3y ago
  How lossy is transcoding at the RF level of an already lossy medium?
  - actionfromafar 3y ago
    It's much better than any other existing technology to capture VHS. It bypasses all analog processing of the signal by the VHS player and captures the video signal directly from the tape head. All further processing is then done in software. If any improvements in software processing is made, the "raw" capture can then be reprocessed with better results.
    - bitwize 3y ago
      So it's like a Kryoflux for VHS tapes? That is cool.
      - actionfromafar 3y ago
        Ha, adding that to my parlance! It's exactly like Kryoflux for VHS tapes. An example - S-VHS tapes can not be played back in regular VHS players. They can't handle the format. But with vhs-decode, it doesn't matter. A regular cheap VHS player can "rip" an S-VHS tape. And decode the HiFi FM-stereo signal, too.
      - rainbowzootsuit 3y ago
        Or Domesday Duplicator for LaserDisc Preservation.
        gofixurcode 3y ago
        It’s actually a fork of that project!
    - iisan7 3y ago
      Best at capture/preservation, but only theoretically best at playback someday. Currently the best software processing algorithms are imo not on par with video playback quality from the best hardware of the era, especially for damaged tapes. It's hard, although certainly not impossible, to imagine that changing. I'm 100% glad it exists though.
      - actionfromafar 3y ago
        You could always take the best hardware of the era, and capture from that. If you were talking about decks. I'm not sure about playback - the output from vhs-decode looks pretty darn good to me, but I'm not an expert at all in composite video gear.
        iisan7 3y ago
        Right, my language was sloppy but I meant two things-- the quality will still be dependent on the hardware chain, and I should expect that a 'bit perfect' capture of a VHS tape will usually be inferior to one captured from a vintage pro deck. And then regarding processing, I'm not a professional, but I've done several successful restorations using virtualdub and avisynth, and on some degraded tapes I couldn't do nearly as well as whatever magic was going on in the vhs to dvd section of the JVC SR-MV50.
        xattt 3y ago
        Even the best VHS decks from the 80s/90s, which would have been used in production environments and thus “well worn”, would have wear-related quality issues.
        actionfromafar 3y ago
        But that’s the beauty of vhs-decode. The transport mechanism needs to be stable and the head clean. The rest of the player doesn’t matter.
        xattt 3y ago
    - kmoser 3y ago
      Yes, but still don't throw away the original tapes, because if a better (read: more accurate/sensitive) tape head ever becomes available, you'll want to use it to upgrade your capture device and then re-scan the original tapes with even better fidelity.
pkkm 3y ago
It's a fully software-based VHS decoder. It takes the raw signal from a VHS tape, captured with a high speed sampling device, and reconstructs the video on your computer. In theory, this approach should allow higher quality digitization than any physical VHS player - it cuts the analog decoding electronics out of the loop, and it allows you to capture once, then tweak the algorithm and decode many times without disturbing the tape. You could even preserve the raw captures in case better decoding algorithms come out in the future.

deleted 3y ago

[deleted]

pkkm 3y ago

I think the biggest obstacle right now is not the software, but the hardware. The software works, but requires either buying a $300-$500 set of three circuit boards, or finding a specific PCIe capture card and potentially modifying it. If someone made a nicer version of the Domesday Duplicator - single board in a case, $100 to $200 - I think that would make the project a lot more accessible. Even better would be if someone started selling modified VHS players, having replaced their normal electronics with a capture device and a USB3 port. After all, many people don't have a soldering iron or a desktop computer.

actionfromafar 3y ago
If we are talking about serious archiving of lots of tapes, $500 for a capture device is nothing. The labor costs of keeping the actual tape deck(s) in good order is probably going to dwarf. But I have actually toyed with the idea of setting up complete workstations modified player, and a slightly better software UX. Don't know how to reach the market willing to pay for such things, though. For tinkering at home, the specific PCIe capture device is actually quite easy to find, it seems it's still produced for some reason.