S-Video input video artifacts

[eXtremeDevil]

Hi, I'm trying to capture a VHS. I have an August VGB100 Video Capture device:

https://www.amazon.co.uk/august-capt.../dp/B008F0SARC

It has two inputs, composite and S-Video. I understand S-Video offers a higher quality, so I'm trying to use that one to capture. However, compared to composite input, I see some weird artifacts on the video:

Composite:


S-Video:


Sorry about frames not being the same, but I couldn't pause the VHS. But I see the effect is clearly visible. The composite signal may have lower quality, but at least it seems somewhat clean.

I have tried with different S-Video cables and also with another capture device, a Hauppauge USB-Live 2, and the results are the same.

However, I have also tried the same cables and the same capture devices with a Sony Hi8 HandyCam and the effect is less visible with the August device, and nonexistent with the Hauppauge device.

So now I suspect of two things: the VHS player itself, or the SCART to S-Video/Composite device I use, something like this:


Where do you think the problem could be? Am I in the right direction? What is the origin of this effect?

Thanks in advance!

[Sharc]

Your VHS player seems not to support S-Video but Composite only (or the S-Video is not wired to the SCART plug). What model is your player?
If it would support S-Video it would have an S-Video port in addition to the SCART - and you wouldn't need the SCART adapter. Your adapter cannot convert a Composite signal to S-Video. The S-video signal (Y/C wires) must be provided by the player like your Hi8 camera apparently does.

[eXtremeDevil]

Originally Posted by Sharc

Your VHS player seems not to support S-Video but Composite only (or the S-Video is not wired to the SCART plug). What model is your player?
If it would support S-Video it would have an S-Video port in addition to the SCART - and you wouldn't need the SCART adapter. Your adapter cannot convert a Composite signal to S-Video. The S-video signal (Y/C wires) must be provided by the player like your Hi8 camera apparently does.

If the S-Video is not wired to the SCART plug, how am I getting an image? Could you please explain me something? I thought any SCART output could be converted to any Composite and/or S-Video input, but are you saying not all SCART output ports are the same, internally?

I have actually search for VHS players with native S-Video ports in second hand shops here in my city, but all the players I found had only SCART ports, nothing more. Are the ones with S-Video rarer?

[Sharc]

Originally Posted by eXtremeDevil

If the S-Video is not wired to the SCART plug, how am I getting an image? Could you please explain me something?

Signal crosstalk between wires and/or within the adaptor plug for example.

I thought any SCART output could be converted to any Composite and/or S-Video input, but are you saying not all SCART output ports are the same, internally?

No. For S-Video you need a player which supports it. Typically an S-VHS recorder/player (preferably with TBC) rather than just a VHS recorder/player.
Only S-VHS recorders/players will provide S-Video which is wired to specific pins on the SCART plug (Europe) and/or have a separate S-Video connector.
Again: What is your player model (brand, type)? Does it have a menu setting for "S-Video"? Check the manual.

I have actually search for VHS players with native S-Video ports in second hand shops here in my city, but all the players I found had only SCART ports, nothing more. Are the ones with S-Video rarer?

Yes, S-VHS recorders/players are of higher quality, successors of VHS, more expensive, and equipment in good condition is the longer the more difficult to find. In Europe the S-Video (if the player supports it at all) is usually also wired to the SCART plug on dedicated pins.
Maybe take a look here:
https://vcrshop.com/category/vcr/
Look for 'S-VHS' or 'SUPER-VHS' devices. But first read the manual of your equipment to see if it is S-VHS compliant or VHS only. Check the menu settings.

Edit:
If you have to live with Composite use a capture device with a good luma/chroma separating filter. I don't know the August VGB100. The USB-Live 2 is also no masterpiece in this respect. The I-O Data GV-USB2 performs better in this respect.

[eXtremeDevil]

Originally Posted by Sharc

No. For S-Video you need a player which supports it. Typically an S-VHS recorder/player rather than just a VHS recorder/player.
Only S-VHS recorders/players will provide S-Video which is wired to specific pins on the SCART plug (Europe) and/or have a separate S-Video connector.
Again: What is your player model (brand, type)? Does it have a menu setting for "S-Video" at all?

Understood!

Sorry, I forgot to mention the model. It seems to be a Phillips VR 550. I don't have the remote right now, so I cannot access the menu, but after your explanations, I doubt it has S-Video capability.

Originally Posted by Sharc

Yes, as S-VHS recorders/players are of higher quality, successors of VHS, more expensive, and equipment in good condition is the longer the more difficult to find. In Europe the S-Video (if the plyer supports it) is usually also wired to the SCART plug.
Maybe take a look here:
https://vcrshop.com/category/vcr/

Understood, my father bought this VCR back in the day, but I doubt it was a higher quality one. I guess I'll stick with composite, it is not worth the cost of buying a higher model for what I want to digitalize.

Originally Posted by Sharc

Signal crosstalk between wires and/or within the adaptor plug.

I'm not sure I get this. If my VCR does not have S-Video capability, how can I see the image? Is it something like "some pins are missing so you see something, but with artifacts, because of the specific S-Video pins not being present?

BTW, another question not related to this topic (sorry): Where does the wobble effect come from? I mean the typical, not a hard one that makes the video impossible to watch. I tried to find info but I had no success. Is it the VCR motor, or is it the tape? Just curious about this.


Thanks in advance!

[Sharc]

The Philips VR500 is VHS only. No S-video capability.

The wobbling comes from time base errors (old tapes, poor/worn equipment ...).
It can be suppressed by using a TBC (TimeBaseCorrector) function as provided internally by high end S-VHS players, or by using extra external equipment. A low cost variant for stabilizing the picture would be to use a (recommended) DVD-recorder in passthrough mode, means in an arrangement like your player -> DVD recorder in passthrough with Composite IN -> S-video OUT -> capture device S-video IN.

[eXtremeDevil]

Cool, thanks for all the information!

[Sharc]

You get these artifacts when you inject a Composite signal into the S-video port (Y wire) of your capture device. Apparently your VHS player (plus adapter) simply loop the Composite signal to the Y wire of the S-video connector or the Y pin of the SCART connector
https://mega.nz/file/WJkE2STR#6GNZYO...9WmH8gvtyOl3rA

[eXtremeDevil]

Thanks for making the time to investigate the details!

[RetsimLegin]

Passthrough is happening all the time. You feed it your source signal and, alongside anything else you might be doing to it (recording it, for example) in the Pioneer, it outputs that signal at its output ports. Intended so you can monitor what you are doing.

Have you consided recording it first onto the Pioneer itself? And then extracting it by burning to a writable (I'd use a good RW so I can reuse it) disc and extract that onto your computer for any further work?

[eXtremeDevil]

Originally Posted by RetsimLegin

Passthrough is happening all the time.

Of course, I get it now, but I thought it was a special mode where the DVR would carry the signal almost "as is". What you say is true, but if I press the display button on the DVR for example, the carried VHS signal will also have the on screen info, the DVR OSD, so it is not purely the VHS signal just carried. That's why I thought it was a special passthrough mode.

Originally Posted by RetsimLegin

Have you consided recording it first onto the Pioneer itself? And then extracting it by burning to a writable (I'd use a good RW so I can reuse it) disc and extract that onto your computer for any further work?

I have consider it, but when recording, the quality is reduced and the video somewhat encoded. I want the pure source signal to encode it myself.

[RetsimLegin]

Originally Posted by eXtremeDevil

I have consider it, but when recording, the quality is reduced and the video somewhat encoded. I want the pure source signal to encode it myself.

I'm pretty certain that there are recording "quality" settings you can adjust to get the best out of it. The highest quality setting should not produce any visible artefacts. It's important, of course, to match the TV standard as well (although from recollection, if you do that wrong it won't record anything.) My own past experiences in doing exactly this suggest to me there is no negative impact on viewing such a recording vs. watching the tape directly.

When you later burn it to a disc, you do so in "high speed" mode which does not change the video at all. Not even slightly. And when you extract it to your computer - ditto.

So you have on your PC the first (digital) generation of what you recorded. Just as you would, in fact, if you captured it onto the computer.

If I were to conjecture an advantage - computers are often and frequently busy doing other things you don't see. There is always the possibility that it does something over which you have no control while you are capturing but which interrupts it such that you get a glitch in your capture. (e.g. something else accesses your hard drive). Whereas a dedicated recorder has one sole purpose, is designed and optimised to do just that one thing. And it leaves you free to do something else (on your PC if you like) while that tape is playing....

[Sharc]

Originally Posted by RetsimLegin

Have you consided recording it first onto the Pioneer itself? And then extracting it by burning to a writable (I'd use a good RW so I can reuse it) disc and extract that onto your computer for any further work?

Legacy DVD recorders encode the video on the fly as mpeg2 with all its compromises. While being a simple process and giving for some users an acceptable quality, it is clearly inferior compared to making a lossless capture, post process it (denoising, deinterlacing, color and levels adjustments etc.) and then encode it offline using an advanced encoder like x264 / AVC or x265 HEVC. Of course the more elaborate procedure has its pitfalls one has to be aware of and know how to cope with for producing decent results.

Post processing mpeg2 recorded stuff requires re-encoding which once more is a quality hit. An option would be to use take the digitized signal from the HDMI output (if available) of the recorder.

[RetsimLegin]

Originally Posted by Sharc

Legacy DVD recorders encode the video on the fly as mpeg2 with all its compromises.

Quite true. But
a) a high (max) bitrate (= high "quality") minimises these to what I'd consider practically indistinguishable from lossless
b) and in any case the source here is (S-)VHS which is intrinsically a massive compromise. You can't make a silk purse, as they say.

And there is no such thing as lossless capture. The very fact of sampling an analog signal, regardless of where it's done, is liable to cause something. Now, how good is that capture card/dongle?

[Sharc]

Originally Posted by RetsimLegin

Quite true. But
a) a high (max) bitrate (= high "quality") minimises these to what I'd consider practically indistinguishable from lossless
b) and in any case the source here is (S-)VHS which is intrinsically a massive compromise. You can't make a silk purse, as they say.

And there is no such thing as lossless capture. The very fact of sampling an analog signal, regardless of where it's done, is liable to cause something. Now, how good is that capture card/dongle?

All this has been discussed to death. If one is happy with what can get from his (noisy) tapes recorded as mpeg2 (blocky) DVDs so be it.
I agree though that it's a simple and (widely) fool-proof process for obtaining mediocre satisfactory results. To each his own

[lollo2]

Originally Posted by RetsimLegin

a) a high (max) bitrate (= high "quality") minimises these to what I'd consider practically indistinguishable from lossless

Never. Here a comparison, using the best quality DVD Recorder https://www.digitalfaq.com/forum/vid...-device-3.html
For other recorders, the gap is higher.

Originally Posted by RetsimLegin

b) and in any case the source here is (S-)VHS which is intrinsically a massive compromise. You can't make a silk purse, as they say.

Not at all. S-VHS (and VHS) looks nice if captured properly. Have a look here (and consider that YouTube degrades the video) https://forum.videohelp.com/threads/...eo#post2654664

Originally Posted by RetsimLegin

And there is no such thing as lossless capture. The very fact of sampling an analog signal, regardless of where it's done, is liable to cause something. Now, how good is that capture card/dongle?

You are confusing A/D conversion and codec. The first has small impact if done by proper hardware, i.e. looking a well digitized signal on a modern player is not worse than whatching the analog output signal from the VCR on a legacy CRT. The codec (lossless versus crap MPEG2 at standard bitrate or versus DV) plays a significant role, especially if further restoration is planned.

[eXtremeDevil]

Originally Posted by Sharc

Legacy DVD recorders encode the video on the fly as mpeg2 with all its compromises. While being a simple process and giving for some users an acceptable quality, it is clearly inferior compared to making a lossless capture, post process it (denoising, deinterlacing, color and levels adjustments etc.) and then encode it offline using an advanced encoder like x264 / AVC or x265 HEVC. Of course the more elaborate procedure has its pitfalls one has to be aware of and know how to cope with for producing decent results.

Post processing mpeg2 recorded stuff requires re-encoding which once more is a quality hit. An option would be to use take the digitized signal from the HDMI output (if available) of the recorder.

This. In any case, RetsimLegin, I'm planning on watching the capture later to see if there was any errors, so I can try again.

You guys thinks DVR HDMI out would have better quality than S-Video out, given the analog source and how is taken from the VHS, a SCART/composite cable?

[Sharc]

Originally Posted by eXtremeDevil

You guys thinks DVR HDMI out would have better quality than S-Video out, ....

Not really, but it saves an D/A and A/D conversion step.
For more info read and translate from here:
https://gleitz.info/forum/index.php?...en-und-andere/

[eXtremeDevil]

Originally Posted by Sharc

Not really, but it saves an D/A and A/D conversion step.
For more info read and translate from here:
https://gleitz.info/forum/index.php?...en-und-andere/

I'll have to translate that and read it, thanks

EDIT

After a quick look, given that I don't have a S-VHS player, or any particular high quality cables, and since I would have to buy at least to new devices, a HDMI capture device and a HDMI splitter, and I don't want to spend much on it, I guess it won't be worth the quality difference.

[eXtremeDevil]

Very well explained!