(2020-09-06, 01:52 PM)pipefan413 Wrote: This is somewhat out of scope for this thread so I apologise if I should be asking elsewhere.

If I'm only interested in capturing video from LaserDiscs for no reason other than to sync audio more precisely, I am assuming that the capture device can be just about any old crap, theoretically (even some absolute howler like this). My main concern would be dropped/duplicated frames.

Does anybody have a rec for a cheap and nasty capture device that might be sufficient for capping video purely to aid audio sync? Or does it just not matter at all, realistically?

If you have a free PCI slot, there's a plethora of old cards you can get used for next to nothing. They should be good enough for a rough capture.

The most important thing is being able to capture YUY2 so that a clean IVTC can be done which will help immensely with frame syncing. If a video reference is all you need then it doesn't matter if the colour/contrast are off.

Obviously if capturing bit-perfect you'll need to run a parallel audio capture so you need a quick enough system to be able to capture without dropping frames/audio, you'll probably end up capturing the analogue audio alongside the digital which helps to line things up when audio syncing

I was able to capture lossless video (HuffYUV) and bit-perfect lossless audio (WAV) using a Core 2 Duo 6300 dual core 1.86GHz made in 2007, so I guess any half decent PC should be able to capture at the same quality; still, a PCI or PCIe card is highly reccomended, and there are really cheap ones around... but some homeworks are needed to find the right one!

(2020-09-06, 10:28 PM)zoidberg Wrote: The most important thing is being able to capture YUY2 so that a clean IVTC can be done which will help immensely with frame syncing. If a video reference is all you need then it doesn't matter if the colour/contrast are off.

Obviously if capturing bit-perfect you'll need to run a parallel audio capture so you need a quick enough system to be able to capture without dropping frames/audio, you'll probably end up capturing the analogue audio alongside the digital which helps to line things up when audio syncing

Yep, that's the plan. I have no idea about being able to cap YUY2 though, that's the sort of thing I'm wondering about what I use to capture. Do you know if these crappy £6 USB EasyCap things would manage that? At a glance, it seems like maybe they can: https://obsproject.com/forum/threads/eas...#post-2440

But yeah, I think I want to basically record the following in parallel:

1. Video over whatever crappy capture device I can manage (analogue) for basically no reason other than to sync the audio by providing a structural frame to hang it on
2. Digital audio from TOSLINK, probably via Reaper
3. Analogue audio from RCA, possibly via VirtualDub or similar (alongside the video)

I'm also planning on running every Dolby Stereo / Ultra Stereo track twice: once to capture the bit perfect track, then once more to capture it through a hardware Dolby decoder (I actually have two I want to try, one that's a consumer Pro Logic one before PLII landed, and another that's the actual studio Dolby SDU4 with XLR in/out). I might actually be best to just run the bit perfect caps back through after recording them, so that the RCA sound card output is sent to the RCA/XLR Lt & Rt inputs of the hardware decoder being used at the time and then the RCA out of the Yamaha is sent back to the RCA in of the sound card's daughter card (which is all shielded and gold plated etc.) or the XLR out of the Dolby is sent along XLR-TRS balanced cables to an audio interface, depending on which hardware I'm using to de-matrix. I reckon I might do this part at the highest practical sample rate depending on the capture device (e.g. 192 Hz) since it's in the analogue realm at this point. Then I'll align the 4-channel recordings to the original captures (and archive those as 24-bit 4.0 FLAC) and do the resync at 32-bit floating point 192 kHz before finally resampling to 48 kHz and applying auto-blanking dither to minimise degradation and noise. I'll then encode the final synced files to DTS-HD MA 4.0 and test. If I'm unconvinced that the encode is playing back correctly, I may try other things like 5.0 (duplicating the surround channel and dropping its gain accordingly) and maybe even something bizarre like 7.0 to see what my 7.1 AVR does with that (so that all the surrounds contain the same channel but with the gain dropped; theoretically shouldn't sound different from the 4.0 but depends what the AVR makes of it).

(2020-09-06, 11:48 PM)spoRv Wrote: I was able to capture lossless video (HuffYUV) and bit-perfect lossless audio (WAV) using a Core 2 Duo 6300 dual core 1.86GHz made in 2007, so I guess any half decent PC should be able to capture at the same quality; still, a PCI or PCIe card is highly reccomended, and there are really cheap ones around... but some homeworks are needed to find the right one!

And yeah, I'm running a high end AMD CPU on an ASUS ROG STRIX X470-F, which is a pretty capable setup, but it's already got quite a lot running on the PCIe lanes. On top of a big chunky butt dedicated GPU (which isn't quite top of the line but ain't no slouch either), I'm also running a 2 TB nVME SSD and am about to add a ZXR sound card as well, which takes up a fair bit of space. So I dunno how viable / wise it would be to cram something else into the limited PCIe area of the board.

If I can cap video with audio over an atrocious USB capture thingy that looks really bad but can still be accurately IVTCd, I'll be happy enough for now. It would perhaps be useful to do an actually good cap of the video at some point for preservation purposes but I'm not overly concerned about it just yet because I'm already spending more than I can reasonably afford to get the recording hardware and LD player (not to mention the actual LDs themselves). That said, if a USB capture device is going to screw up the IVTC or whatever, then it isn't worth the money saved, so maybe I'd be better with something else (BlackMagic Design Intensity Pro or similar)?

I'm excited! Need to secure an LD player now, have put in an offer but seller hasn't responded yet... also waiting to confirm payment for 2 very exciting LDs that were the whole reason I finally took the plunge and decided I'm going to give this capturing malarky a bash.

Even the very cheap low quality USB cap device I first had could capture YUY2 which is 4:2:2 chroma subsampling.

And yes even the most modest computer should be capable of capping lossless SD (LAGS for example) and a separate WAV file simultaneously as long as a separate fast HDD is used for storage (not the OS HDD). But don't capture uncompressed video as the files are huge!

If you capture the analogue audio using the capture device (ie recording an AVI with both video and audio) then you know for sure the audio is in sync and any bit-perfect audio captured alongside can be easily synced to the video.

@pipefan413

Why do two separate captures instead of just running the captured audio track through your sound card outputs into the device and record that? Then it will be in sync already.

Also, I think 192 kHz is probably overkill, depending on what you want to capture. I do use 192 kHz for my favorite vinyl records, but they at least theoretically are able to have that kind of high frequency content (not that it would be audible). VHS is, I believe, technologically limited, so at some point you just aren't getting any info anymore. I think Laserdisc will be much the same story.

P.S. Part of the reason I recommended old PCI cards, some like the BT878 chipset aren't sensitive to Macrovision from what I read, so you don't need to spend a lot of extra cash on a TBC if you want to record commercial VHS stuff and the likes. I believe all modern devices have Macrovision protection, from what I read anyway.

(2020-09-07, 12:32 AM)zoidberg Wrote: Even the very cheap low quality USB cap device I first had could capture YUY2 which is 4:2:2 chroma subsampling.

And yes even the most modest computer should be capable of capping lossless SD (LAGS for example) and a separate WAV file simultaneously as long as a separate fast HDD is used for storage (not the OS HDD). But don't capture uncompressed video as the files are huge!

If you capture the analogue audio using the capture device (ie recording an AVI with both video and audio) then you know for sure the audio is in sync and any bit-perfect audio captured alongside can be easily synced to the video.

Exactly my logic, yes!

I wouldn't bother with uncompressed video, certainly not for my current purposes.

Basically what I want is currently two main things:

1. NEAR DARK [ID6585HB] Ultra Stereo PCM, digital and analogue (curious to compare the dynamics and frequency response of both)

2. THE EXORCIST [10JL-1007] mono PCM, analogue only (already captured but without the video so it's harder to sync accurately; I'd be grabbing the video with audio simultaneously to confirm sync accuracy, since this is a crucial track to preserve properly imo)

And once those are done, bonus round...

3. STREETS OF FIRE [42871] Dolby Stereo PCM with video, again to confirm sync (since @HippieDalek already has this, might be easiest if I figure out a cheap-ass capture device and send info about workflow rather than me buying a separate copy of the LD or asking to arrange some kind of tracked shipping round trip, although I guess we're both in the UK at least)

4. HACHIKO MONOGATARI [SF050-1394] mono PCM, analogue only (the DVD and Blu-ray audio is pretty terrible and has at least one extremely noticeable glitch that sounds like a digital capture/conversion problem to me, so I'm hoping the LD won't have the issue)

(2020-09-07, 01:08 AM)TomArrow Wrote: Why do two separate captures instead of just running the captured audio track through your sound card outputs into the device and record that? Then it will be in sync already.

Because to record all of that at once I'd need to be recording 2 channels on the ZXR (RCA L + R) plus 4 simultaneous inputs through some other audio interface (4 x XLR-TRS for the Dolby SDU4 or 4 x RCA for the Yamaha) but I can't do that atm mostly because I don't have an audio interface with 4 inputs but also because the Yamaha outputs RCA and I don't really want to spend even more money getting RCA-TRS cables in addition to everything else at this point. In terms of sync, the audio interface is going to need to be USB, and that has latency, so I dunno if it can really be assumed to be in sync without slight adjustment for latency. I am considering grabbing a Behringer UMC404HD or similar at least for capturing the SDU4 XLR output (using XLR-TRS balanced cables that I've got already).

(2020-09-07, 01:08 AM)TomArrow Wrote: Also, I think 192 kHz is probably overkill, depending on what you want to capture. I do use 192 kHz for my favorite vinyl records, but they at least theoretically are able to have that kind of high frequency content (not that it would be audible). VHS is, I believe, technologically limited, so at some point you just aren't getting any info anymore. I think Laserdisc will be much the same story.

I'm sure you're right! I could cap it at 96 or 48 kHz instead, and indeed 48 kHz might make most sense considering that's going to be the final sample rate in any case. Somebody suggested that it might be worth capturing at a higher sample rate for analogue and then downsampling after, so I was considering that as a possibility. I still am, though I don't know if it would necessarily do much apart from increase file sizes a bit.

(2020-09-07, 01:20 AM)pipefan413 Wrote:

(2020-09-07, 01:08 AM)TomArrow Wrote: Why do two separate captures instead of just running the captured audio track through your sound card outputs into the device and record that? Then it will be in sync already.

Because to record all of that at once I'd need to be recording 2 channels on the ZXR (RCA L + R) plus 4 simultaneous inputs through some other audio interface (4 x XLR-TRS for the Dolby SDU4 or 4 x RCA for the Yamaha) but I can't do that atm mostly because I don't have an audio interface with 4 inputs but also because the Yamaha outputs RCA and I don't really want to spend even more money getting RCA-TRS cables in addition to everything else at this point. In terms of sync, the audio interface is going to need to be USB, and that has latency, so I dunno if it can really be assumed to be in sync without slight adjustment for latency. I am considering grabbing a Behringer UMC404HD or similar at least for capturing the SDU4 XLR output (using XLR-TRS balanced cables that I've got already).

No, I meant recording normally the first time. And then just running that recorded stuff through one of those devices afterwards. It will only use up an extra output, not an extra input. Latency is auto-corrected in DAWs like Cubase to my knowledge, so that wouldn't be an issue. In either case it would be a fixed delay and incredibly easy to adjust, whereas a whole second capture from an analogue source might very well have changes in speed over the entire duration leading to a non-constant desync.

(2020-09-07, 01:20 AM)pipefan413 Wrote:

(2020-09-07, 01:08 AM)TomArrow Wrote: Also, I think 192 kHz is probably overkill, depending on what you want to capture. I do use 192 kHz for my favorite vinyl records, but they at least theoretically are able to have that kind of high frequency content (not that it would be audible). VHS is, I believe, technologically limited, so at some point you just aren't getting any info anymore. I think Laserdisc will be much the same story.

I'm sure you're right! I could cap it at 96 or 48 kHz instead, and indeed 48 kHz might make most sense considering that's going to be the final sample rate in any case. Somebody suggested that it might be worth capturing at a higher sample rate for analogue and then downsampling after, so I was considering that as a possibility. I still am, though I don't know if it would necessarily do much apart from increase file sizes a bit.

Well it can't hurt much I suppose. Keep in mind that ADCs (analogue digital converters) commonly found in soundcards/interfaces tend to produce more noise at higher sample rates, even in the audible range. Strange but true. It tends to be around 5-10 dB I think between 48 kHz and 192 kHz. Honestly not a big deal with a good ADC since the noise level is very low to begin with and VHS/LD (at least the analogue track) will almost certainly have a higher noise floor than that anyway, but something to keep in mind. It might also worsen distortion characteristics, however I'm just guessing there and I might very well be wrong about that.

(2020-09-07, 01:32 AM)TomArrow Wrote: No, I meant recording normally the first time. And then just running that recorded stuff through one of those devices afterwards. It will only use up an extra output, not an extra input. Latency is auto-corrected in DAWs like Cubase to my knowledge, so that wouldn't be an issue. In either case it would be a fixed delay and incredibly easy to adjust, whereas a whole second capture from an analogue source might very well have changes in speed over the entire duration leading to a non-constant desync.

OK no you've lost me hahah. Might be because it's nearly 1am.

I am intending to record the digital output from the player over TOSLINK to sound card's daughter card first, which I'll be doing simultaneously with the video for sync purposes. Then, separately, I'd run that recorded (hopefully bit perfect) digital track out of the sound card via RCA, to the stereo inputs of either the Yamaha or Dolby hardware decoder, then back to either the input of the sound card (for the Yamaha, RCA) or the input of a USB audio interface (XLR-TRS, for the Dolby SDU4). I can't currently capture all 4 output channels simultaneously in either case, so I'd need to capture 2 at a time (probably L+R then C+S). Or as I put it in the original post...

(2020-09-06, 11:56 PM)pipefan413 Wrote: I might actually be best to just run the bit perfect caps back through after recording them, so that the RCA sound card output is sent to the RCA/XLR Lt & Rt inputs of the hardware decoder being used at the time and then the RCA out of the Yamaha is sent back to the RCA in of the sound card's daughter card (which is all shielded and gold plated etc.) or the XLR out of the Dolby is sent along XLR-TRS balanced cables to an audio interface, depending on which hardware I'm using to de-matrix.

What exactly are you suggesting I do instead? Or are you saying that I should do what I just said?

In terms of repeating captures from an analogue source causing some sync drift, well, this is something I'm concerned about and have already been thinking about a lot. That being said, the *source* is most likely going to be digital unless there's some significant reason that the analogue tracks end up being better (dynamically or whatever); it's just that to capture the 4 channels, I'm probably going to need to record 2 channels at a time.

Buuuut I think all of this is getting a little bit off topic for this particular thread. It might be best if we move over here if we continue this chat (which I'd like to, fwiw).