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Old 4th February 2022, 20:22   #1  |  Link
andiandi
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merange and camcorder footage

Hi,

I want to rip some VHS recorded with a camcorder, but I noticed that it require a lot of bitrate for this kind of footage.

Given that the videos aren't grainy at all (but rather very smooth), I assume that it's because of camera shake (due to handheld shooting). If that's the case, I wondered if increasing merange value could help (even for an SD source) ?

Thank you.

Last edited by andiandi; 4th February 2022 at 20:33.
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Old 8th February 2022, 02:16   #2  |  Link
benwaggoner
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Camera shake itself isn't too bad, but if the shutter speed was low, motion blur can further complicate things. --me-range won't help that. --preset placebo may be a good starting point (still faster than realtime for standard def sources on a reasonably modern CPU).

Can you share your settings? Maybe a sample?

VHS tapes can be both smooth as in low detail but still noisy. What a horrible format. Circa 1996 I charged an extra $20/minute for encoding from VHS sources. That was mainly to get people motivated to go find their Beta SP masters.

VHS also typically requires horizontal cropping, at least 8 pixels left and right (so 704x out of a 720x capture).
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Old 9th February 2022, 20:30   #3  |  Link
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Quote:
Originally Posted by benwaggoner View Post
Camera shake itself isn't too bad, but if the shutter speed was low, motion blur can further complicate things. --me-range won't help that. --preset placebo may be a good starting point (still faster than realtime for standard def sources on a reasonably modern CPU).

Can you share your settings? Maybe a sample?

VHS tapes can be both smooth as in low detail but still noisy. What a horrible format. Circa 1996 I charged an extra $20/minute for encoding from VHS sources. That was mainly to get people motivated to go find their Beta SP masters.

VHS also typically requires horizontal cropping, at least 8 pixels left and right (so 704x out of a 720x capture).
Here are my settings :

cabac=1 / ref=4 / deblock=1:-1:-1 / analyse=0x3:0x133 / me=umh / subme=9 / psy=1 / psy_rd=1.00:0.15 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-3 / threads=6 / lookahead_threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=4 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=crf / mbtree=1 / crf=20.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00


A short sample :

https://mega.nz/file/4rolHKJC#y3DjM4...7onHpbsYzhl8BI

archive pw : pop5213
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Old 9th February 2022, 21:22   #4  |  Link
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The sample is blocky PAL MPEG-2 6,8Mbps to begin with...
Is that your source ? Recapturing with a better device seems appropriate here, almost all details are lost already.
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Old 9th February 2022, 22:51   #5  |  Link
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Was this originally captured with Hi-8 or similar, played to some VHS recorder and then converted somehow to MPEG-2/DVD ?

Tricky, I would go back to the best preserved source and try to play that back to some TV capture card and go from there. I have footage of me when I was sub- 10 years old that was originally on 8mm and it took the -> VHS -> TV-Capture route and that looks better than your sample.

The problem is capture cards where you can connect a VHS player or Hi-8 camcorder were kinda discontinued with the introduction of HDMI. If you still have such 'ancient' devices available, good luck... otherwise it is what is is, keep the MPEG-2 capture? Tell us your options here

I would like to note that just because 'right now' there is no satisfactory solution for you it does not mean that in the 'future' better options for capture, processing, filtering or encoding will not be available. So if your goal is to preserve the content: do the best analog AND digital storage of the content you can and wait. Not happy with the results you can get now? Wait 10 years and look into it again.


And no, encoder settings won't safe you here.
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Old 9th February 2022, 23:47   #6  |  Link
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Wow. Yeah, is not going to be easy to fix.

First, you want to use a deblocking MPEG-2 decoder, because you've got a whole lot of macroblock edges apparent.

I'd start by cropping 22 left, 24 right, 4 top, 12 bottom to get to active image area. I bet someone has a AVISynth or FFmpeg filter that can fix horizontal blanking interval problems in a digital source. That would get some stability back to the image.

I'd also use a really good motion-adaptive deinterlacer to convert 25i to 50p to preserve the interlaced temporal information, because there's just not much spatial info there.

Big picture, this is NOT an encoding problem, but a source problem, and taking it from terrible to "I can see mediocre from here" is going to take a deep dive into advanced preprocessing. There's no tweaking in x264 that can make it look better than the frames that go into x264, which will be horrible with the source as is.


I am enormously grateful I don't need to deal with sources like that any more!
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Old 10th February 2022, 17:43   #7  |  Link
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Originally Posted by Emulgator View Post
The sample is blocky PAL MPEG-2 6,8Mbps to begin with...
Is that your source ? Recapturing with a better device seems appropriate here, almost all details are lost already.
Yes and no. This source was ripped about 15-16 years ago with a DVD recorder from an older VHS (itself copied from a VHS-C) .
I'm using this source for tests and to "lay the groundwork". I still have the original VHS-C (from which the VHS was copied decades ago) but I don't know yet if it's better preserved (I have to clean my VCR first before testing).

But I wonder, when you mention the fact that's it's in MPEG-2 6,8Mbps do you mean the quality and/or codec isn't good enough for a VHS source ? I don't know much about MPEG-2, but I always thought it was "DVD Quality" and so more than enough for SD sources in general.

This is fundamental because I bought this capture device which records in MPEG-2 : https://www.amazon.co.uk/Capture-Ver.../dp/B00TFNP4BS

Initially, I wanted to buy this one (which records in H264) : https://www.elgato.com/en/video-capture, but it's said to record at 1400Mbps which seems insufficient.

Last edited by andiandi; 10th February 2022 at 19:43.
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Old 10th February 2022, 18:02   #8  |  Link
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Originally Posted by rwill View Post
Was this originally captured with Hi-8 or similar, played to some VHS recorder and then converted somehow to MPEG-2/DVD ?

Tricky, I would go back to the best preserved source and try to play that back to some TV capture card and go from there. I have footage of me when I was sub- 10 years old that was originally on 8mm and it took the -> VHS -> TV-Capture route and that looks better than your sample.

The problem is capture cards where you can connect a VHS player or Hi-8 camcorder were kinda discontinued with the introduction of HDMI. If you still have such 'ancient' devices available, good luck... otherwise it is what is is, keep the MPEG-2 capture? Tell us your options here
Basically, yes : It was captured on VHS-C through a camcorder -> VHS-C to VHS with VCR -> VHS to DVD with DVD recorder.
I still got the original VHS-C but considering how old they're, I just hope they're better preserved than this DVD source.

Are the capture devices I linked above good enough or is there better methods that I don't know ?
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Old 10th February 2022, 18:12   #9  |  Link
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Originally Posted by benwaggoner View Post
Wow. Yeah, is not going to be easy to fix.

First, you want to use a deblocking MPEG-2 decoder, because you've got a whole lot of macroblock edges apparent.

I'd start by cropping 22 left, 24 right, 4 top, 12 bottom to get to active image area. I bet someone has a AVISynth or FFmpeg filter that can fix horizontal blanking interval problems in a digital source. That would get some stability back to the image.

I'd also use a really good motion-adaptive deinterlacer to convert 25i to 50p to preserve the interlaced temporal information, because there's just not much spatial info there.

Big picture, this is NOT an encoding problem, but a source problem, and taking it from terrible to "I can see mediocre from here" is going to take a deep dive into advanced preprocessing. There's no tweaking in x264 that can make it look better than the frames that go into x264, which will be horrible with the source as is.


I am enormously grateful I don't need to deal with sources like that any more!

Alright, are these macroblock edges caused by MPEG-2 codec or is this an issue with this specific source ? I prefer to use the best codecs and devices so that I won't have to rip these tapes again when they'll be even older.

Filters could be a good option even though I hope the original sources don't have these issues (if you have some example of filters so that i can test them).

Last edited by andiandi; 10th February 2022 at 18:21.
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Old 10th February 2022, 20:58   #10  |  Link
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Originally Posted by andiandi View Post
Basically, yes : It was captured on VHS-C through a camcorder -> VHS-C to VHS with VCR -> VHS to DVD with DVD recorder.
I still got the original VHS-C but considering how old they're, I just hope they're better preserved than this DVD source.

Are the capture devices I linked above good enough or is there better methods that I don't know ?
The problem with the capture devices you linked is that they are doing compression internaly so they can send the data over USB ready to be decoded/written to disk. The Analog -> Digital conversion they do is most likely really bad too. They do their job like some butcher in a large meat factory.

The Mpeg2 capture device you linked probably has not much going for it except "Gold Contacts for the highest quality".
The H.264 device from elgato with its 1.4Mbit max rate may be slightly better or worse, I dont know. The PCI-E HDMI cards on the elgato.com website look good on paper though as they target pro streamers.

What I had in mind is capturing uncompressed and using that. Back then one did that with some TV-Tuner card recording uncompressed to harddisc. Now these are no longer produced as everything is digital with HDMI.

There is a VHS to digital tutorial in german (Google Translation might help) here:
https://gleitz.info/forum/index.php?...en-und-andere/

They took the "VHS -> DVD Recorder ( for SCART TO HDMI ) -> HDCP Remover -> Blackmagic Intensity Capture card" route.

I lack expertise if a high quality SCART -> HDMI converter can replace their DVD Recorder approach.

Retro Gamers have problems with connecting old SCART consoles to HDMI in high quality for example, here some recommend SCART -> HDMI adapters above ~60USD as a minimum, higher is better. I think the analog to digital conversion is the break point in such a setup, so please if you go that route dont buy some crappy 10$ adapter. Here higher cost might mean better builtin components or algorithms for upscaling etc.

I have not followed the video capture stuff ( for live processing ) since 10 years but back then I used Blackmagic too, they were really good cards to grab unprocessed frames.

This is leaving my area of expertise, please - someone else chime in.
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Old 11th February 2022, 01:14   #11  |  Link
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I can suggest to revive the camcorder or make the VHS-C adapter cassette ready (test both for not munching tape)
and go from that VHS-C into a Blackmagic Intensity Shuttle (~200USD)
capturing CVBS from yellow cinch or S-Video 4-pin Mini-DIN into uncompressed 10bit YUV.
Needs Win7-Win10, a dedicated USB 3.0 port on MB, and I suggest a SSD to capture upon.
Notebook owners beware:
Some USB3.0 Expresscard adapters negotiate only 10% of USB3.0 bandwidth, the shuttle wants to see 40% or bust.

That might be the best capture for the buck you can get since 2018..2022 and then you may go the avisynth route of restoration:
QTGMC to 50p?, crop?, stabilize?, resize to 1280x720x50p?, chroma correction?, denoise?, sharpen? regrain? edit?
and then feed that preprocessed footage to the encoder.
The result should be worth the effort now, and encoding with x264 to blu-ray compatible
should leave you with something ready for blu-ray, or muxing into .mkv, playable on the majority of devices.

If the 200USD are to much for that single task:
A lot of DV Handycams are dead cheap now (I used a Sony PC-100 for this), have an inbuilt TBC and some useful fixed preprocessing.
These can work as passthrough ADC from CVBS into DV-AVI via Firewire 400, (older WinXP and some Win7 notebooks still have this connector).
Canopus ADVC-50-100-300 do the same, but had been more expensive because of a dedicated NEC chip which offers some pre-processing settings (gain, Y/C, Denoise 2D/3D, shadow detail, light detail etc)

DV-AVI@25Mbps is still ok for VHS sources.
I had tiny blockborder artifacts visible only on one particular en-/decoding chain:
Sony Encoder -> WinXP MS quartz.dll decoder and found this only while pixel-peeping the differenced stream.
Back then quartz.dll was guilty, had been silently updated, and since Win7 decoded properly.

Those USB-sticky-realtime-chepo-hardware MPEG-2 encoders are the bottom of the barrel,
and I concur with rwill's comparison to a butcher...
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Last edited by Emulgator; 11th February 2022 at 01:26.
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Old 11th February 2022, 19:11   #12  |  Link
andiandi
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Quote:
Originally Posted by rwill View Post
The problem with the capture devices you linked is that they are doing compression internaly so they can send the data over USB ready to be decoded/written to disk. The Analog -> Digital conversion they do is most likely really bad too. They do their job like some butcher in a large meat factory.

Alright, is this the same issue for all of these capture devices, even best brands like this one for example ? (I assume it is, but that it's probably slighlty better - like the Elgato) :

https://www.amazon.com/Hauppauge-610...s%2C216&sr=8-6

Quote:
Originally Posted by rwill View Post
What I had in mind is capturing uncompressed and using that. Back then one did that with some TV-Tuner card recording uncompressed to harddisc. Now these are no longer produced as everything is digital with HDMI.

It makes me think of some PCI capture cards that I was looking for, like these :

https://www.hauppauge.com/pages/prod...pactvcb-e.html

https://www.avermedia.com/profession...c725b/overview

It seems good on paper, what do you think ?

Last edited by andiandi; 11th February 2022 at 19:18.
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Old 11th February 2022, 19:13   #13  |  Link
andiandi
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Originally Posted by Emulgator View Post
I can suggest to revive the camcorder or make the VHS-C adapter cassette ready (test both for not munching tape)
and go from that VHS-C into a Blackmagic Intensity Shuttle (~200USD)
capturing CVBS from yellow cinch or S-Video 4-pin Mini-DIN into uncompressed 10bit YUV.
Needs Win7-Win10, a dedicated USB 3.0 port on MB, and I suggest a SSD to capture upon.
Notebook owners beware:
Some USB3.0 Expresscard adapters negotiate only 10% of USB3.0 bandwidth, the shuttle wants to see 40% or bust.

That might be the best capture for the buck you can get since 2018..2022 and then you may go the avisynth route of restoration:
QTGMC to 50p?, crop?, stabilize?, resize to 1280x720x50p?, chroma correction?, denoise?, sharpen? regrain? edit?
and then feed that preprocessed footage to the encoder.
The result should be worth the effort now, and encoding with x264 to blu-ray compatible
should leave you with something ready for blu-ray, or muxing into .mkv, playable on the majority of devices.

If the 200USD are to much for that single task:
A lot of DV Handycams are dead cheap now (I used a Sony PC-100 for this), have an inbuilt TBC and some useful fixed preprocessing.
These can work as passthrough ADC from CVBS into DV-AVI via Firewire 400, (older WinXP and some Win7 notebooks still have this connector).
Canopus ADVC-50-100-300 do the same, but had been more expensive because of a dedicated NEC chip which offers some pre-processing settings (gain, Y/C, Denoise 2D/3D, shadow detail, light detail etc)

DV-AVI@25Mbps is still ok for VHS sources.
I had tiny blockborder artifacts visible only on one particular en-/decoding chain:
Sony Encoder -> WinXP MS quartz.dll decoder and found this only while pixel-peeping the differenced stream.
Back then quartz.dll was guilty, had been silently updated, and since Win7 decoded properly.

Those USB-sticky-realtime-chepo-hardware MPEG-2 encoders are the bottom of the barrel,
and I concur with rwill's comparison to a butcher...
Ok, so the best solutions would be :

- 1. Blackmagic Intensity Shuttle
- 2. Maybe PCI capture cards that I linked above (on paper at least)
- 3. DV Handycams
- 4. DVD Recorders ? (I assume that they're way better than USB capture devices when it comes to Analog to Digital conversion but lacks lossless encoding)
- 5. USB capture devices

About deinterlacing : In one of my tests, I converted the video to lossles (UT-Video) to test filesize and because it could help me with editing (easier to cut), but the file was lacking interlacing informations and so when I re-encoded it, the deinterlacing was broken (the video was laggy even with Bob and double framerate). So I wonder if when capturing in lossless, we should take care of setting options for interlacing beforehand ?
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Old 11th February 2022, 22:11   #14  |  Link
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All USB grabbers are more or less crap.

The capture cards you linked are what I had in mind, I used similar ~20 years ago but they are more or less consumer level. Blackmagic Design cards should be higher up so maybe you will have more success with them.

I looked through some threads on video boards regarding VHS to digital (most seem to be in german, i wonder why) and those that had it nailed down went on and on about something called "Band Jitter". There was also the statement that one should NOT go from the VHS player directly into a Blackmagic card or other, cheaper, capture card.
It appears when playing back from VHS slight jitter in playback speed, or with such jitter when it was recorded, will lead to horizontal picture de-synchronization. The problem was tackled by using certain Panasonic DVD recorders for conversion from the VCR output signal to HDMI for stabilization.

It was also noted that using a "Canopus Edius NX" capture card directly connected to a VCR is fine too as it handles that jitter thing. Looks like capture cards that are available to mere mortals such us dont handle "Band jitter".

The DVD recorder you used to record your sample probably did stabilization too so its hard to say what happens when you connect your VHS playback device directly to a newly aquired capture device.

Someone posted a sample capture, one with the Canopus card and one from some USB Grabber on youtube:

https://www.youtube.com/watch?v=fBOG0SuFtrw
https://www.youtube.com/watch?v=qdIaIKRpXq4

So if you get that horizontal wobble from the first video when capturing you have to work on that "Band Jitter" thing.
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Old 13th February 2022, 22:12   #15  |  Link
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All USB grabbers are more or less crap.

The capture cards you linked are what I had in mind, I used similar ~20 years ago but they are more or less consumer level. Blackmagic Design cards should be higher up so maybe you will have more success with them.

I looked through some threads on video boards regarding VHS to digital (most seem to be in german, i wonder why) and those that had it nailed down went on and on about something called "Band Jitter". There was also the statement that one should NOT go from the VHS player directly into a Blackmagic card or other, cheaper, capture card.
It appears when playing back from VHS slight jitter in playback speed, or with such jitter when it was recorded, will lead to horizontal picture de-synchronization. The problem was tackled by using certain Panasonic DVD recorders for conversion from the VCR output signal to HDMI for stabilization.

It was also noted that using a "Canopus Edius NX" capture card directly connected to a VCR is fine too as it handles that jitter thing. Looks like capture cards that are available to mere mortals such us dont handle "Band jitter".

The DVD recorder you used to record your sample probably did stabilization too so its hard to say what happens when you connect your VHS playback device directly to a newly aquired capture device.

Someone posted a sample capture, one with the Canopus card and one from some USB Grabber on youtube:

https://www.youtube.com/watch?v=fBOG0SuFtrw
https://www.youtube.com/watch?v=qdIaIKRpXq4

So if you get that horizontal wobble from the first video when capturing you have to work on that "Band Jitter" thing.
Ok, apparently to prevent this, a TBC (Time Base Corrector) is required, but it's very expensive, or some DVD recorders or even some capture cards as you mentionned, could do the job. And if I understood correctly, the stabilisation of these DVD recorders and capture cards is just slightly imitating what a real TBC would do.
Anyway, capturing VHS tapes is way less easy than I thought (even budget-wise), otherwise there's still the DV solution mentionned by Emulgator.

Thanks a lot for your help. To think I was about to use these crappy USB devices !
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Old 15th February 2022, 23:46   #16  |  Link
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Once it comes to TBC (and poor recordings will ask for that):
The cheapo DV-Cam passthrough solution I mentioned has a very good TBC built in and should get you 80..90% quality.
Coming from the usual 2nd generation VHS you won't miss a thing, source chroma is already all over the place before it sees 4:2:0 DV-AVI 8-bit, and there is AviSynth to get that back in place.

To get the maximum out of all VHS / S-VHS / Video8 / Hi8 sources (maybe 95%) you want to capture into 4:2:2 uncompressed 10bit.
Unfortunately the situation becomes more hairy because most affordable capture devices are rather poorly equipped when it comes to TBC.

From here on for VHS/S-VHS it is recommended to get a S-VHS VCR with a good built-in TBC.
Some JVC decks are reported to get the best out of a VHS, that alone triples the costs. (I haven't tested)
I can speak about Panasonic NV-HS950 (1 field worth of TBC, best detail, costs 5-fold.)
Panasonic AG-7750 (3 big PCBs full of TBC, safest bet, but expensive, costs 10-fold)

The Blackmagic Intensity Shuttle has only 1 line worth of TBC,
that was not enough to cope with old, skewed, 3rd generation recordings here.
A Brighteye BE-75 has a deeper TBC, but is again quite expensive.
So Ben's rates are well reasonable...
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Last edited by Emulgator; 16th February 2022 at 00:01.
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Old 16th February 2022, 20:10   #17  |  Link
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Yes, I have to replace my VCR anyway because the one I got doesn't have TBC and S-Video.
In any case, there are few options for a reasonable budget.

In short, from what I saw there's either the DV Cam solution you suggested, or VCR with built TBC + DataVideo DVK as frame-TBC (generally more affordable compared to other external frame-TBC).

Apart from that, there's the option of using a DVD recorder with TBC-Like as passthrough but given that it's closer from a Line-TBC than a Frame-TBC, it would require a Frame-TBC it the chain on one hand, and it'd probably need to deactivate the TBC of the VCR since it's a Line-TBC as well (at the end, this solution is probably more expensive that it seems). Same with Canopus capture card, which is apparently Line-TBC-like as well (otherwise it would have been worth to prevent ANALOG <-> DIGITAL conversion happening twice or more like it does in passthrough, even though losses in quality should be slight anyway).

It'd be nice if there was "Software TBC" if it's feasible.

Last edited by andiandi; 16th February 2022 at 21:37.
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Old 17th February 2022, 07:34   #18  |  Link
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It'd be nice if there was "Software TBC" if it's feasible.
I have no experience with analog video but I remember reading from a group that is archiving/recovering old floppy disks.

They capture the analog signal from a floppy drive head at high frequency and reconstruct from there, bypassing the older technology in the floppy drives and doing some software based interpretation of the sampled signal, which finally leads to a more or less best effort disk image for corrupted or degraded sectors.

Its an interesting read:
https://scarybeastsecurity.blogspot....ed-floppy.html

The data size required for VHS would probably be truly huge but if someone is looking for a "fun" project..
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Old 18th February 2022, 05:13   #19  |  Link
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Ok, apparently to prevent this, a TBC (Time Base Corrector) is required, but it's very expensive, or some DVD recorders or even some capture cards as you mentionned, could do the job. And if I understood correctly, the stabilisation of these DVD recorders and capture cards is just slightly imitating what a real TBC would do.
Anyway, capturing VHS tapes is way less easy than I thought (even budget-wise), otherwise there's still the DV solution mentionned by Emulgator.
Yeah, it is a hassle. I still have an industrial-grade Panasonic S-VHS deck in cold storage, just in case. That can do S-video out, which can be better than the comb filters in a cheap USB capture card. A good lossless capture card for composite and s-video cost a good $5000 30 years ago, and maybe $150 15 years ago. It seems they should still exist in some form.

Also, USB speed isn't the real issue here. Fully uncompressed standard def video is still less than USB 2.0's bandwidth. The problem is the compressor being used. No cheap hardware encoder is much good. And certainly MPEG-2 is going to give a lot more artifacts than H.264 or ProRes or whatever.

Ah, how times have changed. Uncompressed SD was the holy grail when I was coming up. And now I've been playing with 8Kp120 HDR for a couple of years. That's, uh, 1536x more pixels/sec.
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Old 15th February 2023, 09:34   #20  |  Link
PatchWorKs
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Quote:
Originally Posted by rwill View Post
I have no experience with analog video but I remember reading from a group that is archiving/recovering old floppy disks.

They capture the analog signal from a floppy drive head at high frequency and reconstruct from there, bypassing the older technology in the floppy drives and doing some software based interpretation of the sampled signal, which finally leads to a more or less best effort disk image for corrupted or degraded sectors.

Its an interesting read:
https://scarybeastsecurity.blogspot....ed-floppy.html

The data size required for VHS would probably be truly huge but if someone is looking for a "fun" project..
Well, seems basically the same VHS decode approach:

https://github.com/oyvindln/vhs-decode

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