Freezing, not smooth capturing with JVC TBC and DNR on

[Idan1822]

Hi all
I have this weird problem that I can't find out the reason for it.
I've got this JVC 7960 VCR with TBC + DNR features on.
Only *Sometimes* the video is not going smooth, like frames are freezing for some seconds.
It doesn't happen all the time, and even if I capture the same tape again, it won't appear.

I'm using Intel I7 3770 Machine with Windows 7, 16GB RAM - VirtualDub 1.10.4 with Avermedia C039 card along with S-Video output from the VCR with UtVideo YUV420 compression. (PAL)

Here's a video of the problem VS a standard VCR capture I took few years ago.

https://youtu.be/d0NLcWnkUnM?si=eXAD_GSYIEE7p0wT

I haven't tried much tests like disable the TBC or DNR fetures, nor using different codecs.
What should I look for?

[Sunk]

May I ask why 4:2:0? As far as I understand, 4:2:2 should be the right chroma subsampling for raw VHS capture.

[Idan1822]

I didn't even notice that
Probably a mistake.
I have now changed to 422.

Would that make such an issue?
I have captured almost 20 tapes at 420.
I have 70 more to go.
Should I capture those again in 422?

[Alwyn]

Also, if you're using VDub to capture, Lordsmurf recommends using version 1.9.11, from here:

https://www.digitalfaq.com/forum/video-conversion/1727-virtualdub-filters-pre.html

[Idan1822]

When I changed to 422
I cannot play the .avi file on VLC anymore.
It gives me "Codec not supported: VLC could not decode the format "UMY2" (No description for this codec)"

On Vdub it plays.
Can I open the files on vlc?

[lollo]

Only *Sometimes* the video is not going smooth, like frames are freezing for some seconds.

How is the video connecting the VCR directly to the TV?

[Idan1822]

Only *Sometimes* the video is not going smooth, like frames are freezing for some seconds.

How is the video connecting the VCR directly to the TV?

I did some tests.
When it is connected to the TV, there are no freezing or stuck BUT the video is a bit shaky with TBC/DNR on at those parts.
When I turn the TBC/DNR off, I don't have those kind of shakes.
When capturing-I have no shakes but those types of freezing/not smooth.

I have tried the Video Stabilizer on option (it turns off the TBC/DNR automatically) and the video is really not smooth for all over the tape. like VCD or some slow fps video.

What do you think?
Is it something with the TBC/DNR that fixes the "bad tape" or some kind of that?

[Bwaak]

Over-eager DOC (dropout compensator) replacing mildly damaged frames?

[lollo]

What do you think?

I think that the tape at some point is damaged and the TBC of the JVC is doing its best to provide a clean signal, without being able to do it 100%.

There is not much you can do, maybe try another VCR, such as a Panasonic if you have access to it.

The fact that while capturing the "freezing" may or may not happen it makes me think you may have troubles with your set-up. On the ohter hand, if there is a defect on the tape, only partially fixed by the TBC inside the VCR, your capture device can't do anything to improve the final result.

[Idan1822]

I have found out that my main problem is that the video is not smooth enough like my previous capturing 10 years ago.
I downloaded FPS counter and played both of the files

The old capture is giving me 50FPS (right) and the new one (left) gives me 25FPS.
Both of the files are at 25FPS in the codec info.

Why does the MPEG2 is looking quicker to my eyes and plays like on TV while the lossless is looking some kind of slower?

I have attached a video but I don't know if it's clear to see.

https://youtu.be/gv8-ZkXRYTU?si=gO_OMPQrIbHOzHcA

[Idan1822]

I tried to de-interlace using the filter on Vdub (Double frame rate, top field first)
Results are awesome BUT a 25min 10GB RAW AVI file comes out around 100GB after that.

Is that how it should be?

[Alwyn]

Nah, go into Video>Compression and reset your codec to HUFF or whatever you want to use. It has probably defaulted back to Uncompressed (top of the list).

Doubling the frame rate will double the size of the original lossless file, but of course exporting in say x264 will reduce that down to ~750mb for 25 minutes.

[Alwyn]

Re your above-post, use Mediainfo to analyse; check both videos are the same length (which they will be); the frame rate for the deinterlaced file will be 50.

I think I've noticed the same slight difference; I think the double frame rate messes with your senses when you're comparing them side by side; in most cases, it's definitely smoother and that confuses your eyes/brain.

[Idan1822]

Nah, go into Video>Compression and reset your codec to HUFF or whatever you want to use. It has probably defaulted back to Uncompressed (top of the list).

I always make sure it's on UtVideo YUV422 BT.601VCM before I capture.
It didn't go back to the default.

I try to use Hybrid program right now.
When using de-interlace with x264 - doesn't it make the file non-lossless anymore?

[Alwyn]

It didn't go back to the default.

OK, check the codec of the new file with Mediainfo. I just did a quick check on a UT video I have here: the deinterlaced version (double frame rate) is just under double the size.

When using de-interlace with x264 - doesn't it make the file non-lossless anymore?

X264 is a lossy format so yes, it will be non-lossless. However, I have read there is a setting that will make X264 near-lossless (I can't remember what it is); better ask on the Hybrid thread.

[Idan1822]

Got it sorted with hybrid after processing the file as UT Video and not X264.
Would that be the best option to keep the file lossless for archive?

[Alwyn]

Would that be the best option to keep the file lossless for archive?

Best is to keep your original capture as your archive. Then, in the future, if you become more proficient or keen, you can re-work your original.

[Marshalleq]

I don't know if anyone actually answered your question. But just some anecdotal observations from my growing experience - when I capture via ADVC-100/110 into a MAC I've had none of the issue you described, but when I capture via a Magewell analogue capture card into Windows, I sometimes get the issue you describe. My suspicion is that it is something to do with the operating system and hardware, though I have no hard evidence to base this on. But I do have decades of IT experience and one thing I no for a fact is that Windows is more likely to cause glitches such as this, NIX based OS's such as MacOS can still have issues, but they're more consistent, either they exhibit an issue constantly, or they don't. I'm sure I'll get flamed for that comment, but it's been my (professional) experience.

The machine I experienced this on (just today actually) is a threadripper 2950x, 32 thread CPU with 128GB RAM and a 4090 GPU plus a pro Magewell capture device and of course fast enterprise SSD's. Just to show you that hardware spec isn't the issue and even with this kind of insane spec, performance issues can occur. Perhaps there is something else on the PC that comes to life randomly, sucks up some disk, memory or CPU resources and causes these glitches? Typical contenders for that might be Antivirus software in the background or similar, or just simply windows being windows. But also, not an easy thing to fix for anyone. Take a look at CPU stats while recording, see if it bursts to 100% for example. Basically at this point you should be looking at logs and resource graphs to see what's going on. I hope that is helpful and I hope I don't offend anyone with my Windows comments.

[Alwyn]

But just some anecdotal observations from my growing experience - when I capture via ADVC-100/110 into a MAC I've had none of the issue you described, but when I capture via a Magewell analogue capture card into Windows,

Invalid comparison. DV into a Mac verses analogue into Windows can't be compared. I'll bet if you put DV into Windows (especially your machine) it would go as smooth as silk too.

[Marshalleq]

Invalid no, anecdotal yes.

[dellsam34]

It's a combination of VCR's TBC and capture software, I've had that happens to me with one JVC VCR and not with other VCR's with vdub, this is one of the reasons I don't use vdub for capturing and use a light weight app like MediaExpress. OP you can try AmarecTV, Also check your frame drop count. This couldn't have been a computer issue otherwise it will happen with every VCR.

[Idan1822]

It's a combination of VCR's TBC and capture software, I've had that happens to me with one JVC VCR and not with other VCR's with vdub, this is one of the reasons I don't use vdub for capturing and use a light weight app like MediaExpress. OP you can try AmarecTV, Also check your frame drop count. This couldn't have been a computer issue otherwise it will happen with every VCR.

I have tried AmarecTV now and I get the same results but on different parts on the tape-it's random.
In Vdub I doubled checked, and there were no frame drops.

I see no frame drops on Amarec either but I do see that when it happens, the Cap (25FPS) goes down to 13-16 like in this picture.

[dellsam34]

That's your problem right there, Frame rate should be constant 25fps for PAL, Find out why your capture card driver is lowering it, In a sense that's frame dropping, that's like dropping 21 frames a second.

[Idan1822]

Could be the VCR?
I'm using Avermedia ezmaker 7 c039 capture card.
Tried difrerent drivers and the same result.
I didn't mention but those are VHS-C tapes into adapter.
It happens in the same spot on some tapes and not random on the same tape.

[dellsam34]

Frame drop is not a VCR problem, it's capture device/driver. Try a different capture device.

[themaster1]

Let me guess, capping on the OS hdd directly and now wondering what's happening or a subpar hdd( less than 7200 rpm). Am i right or... am i right ?

[Idan1822]

I've tried capturing to SSD and both mechanical HDD with the same result.

[Idan1822]

Please help me to find a source to my problem.
I've done some more tests.

I'm using Amarec now.
I can see the fps is dropping from 25fps to 21fps (Cap) and 50fps (View) drops to 30-40fps and sometimes even more. that shows me the freezing in the video.
When I *Turn Off* the DNR/TBC of the same VCR! I get almost 25fps all the time (maybe few 24fps) including those parts of the tape.

I've uploaded sample video with and without TBC and the log files from Amarec.
I do not see VERY MUCH differences in the capture video quality either when it's ON or OFF.

Maybe the circuit inside the VCR is not working in good order?

[dellsam34]

The TBC in the VCR cannot fix frame issues, you may need something in between your VCR and capture device such a Panasonic DVD recorder as a passthrough, Alternatively, if this is a software issue try the right settings, there are Wikis for both AmarecTV and Vdub, read them.

[Idan1822]

But this is what I'm trying to say
When the TBC is ON- I get those FPS drops (no frame drops = 0)
When the TBC is OFF - I get NO fps drops (screen attached) - it stays like that - maybe a minor drop to 24.98 for a mil second but not below that like the TBC is on.

I have even tried 3 more standard vcrs with no tbc.
All 3 has exact 25fps.
When I turn ON the tbc on the jvc, fps drops at some points.