JVC S-VHS settings for capture (again)

[lollo]

In one old post https://forum.videohelp.com/threads/399048-JVC-HR-S9600-comparisons#post2597201 I made a reference to a comparison between
the settings of my JVC HR-S9500MS, where I choose the "edit=off" because imho gives the best picture in my case.

However, I have to mention that with this setting there is some ghosting (frame blending?): it appears at scene change and will fade in 2 or 3 frames maximum.
In standard play conditions is not visible but stepping frame by frame is evident.

My suspect is that the NR circuits of the JVC "improving" the picture also generate some defect at scene change. (most of the circuits are inactive with edit=on, except DNR inside TBC)

Attached some pictures.


[Attachment 57967 - Click to enlarge]

edit=off

[Attachment 57971 - Click to enlarge]

edit=on

[Attachment 57972 - Click to enlarge]

another example where the defect is enhanced, on a bad quality program

[Attachment 57970 - Click to enlarge]

So I have to choose between a "better" video with this defect or a "worst" video without ghosting

Did somebody else experienced this behaviour playing with the JVC settings, or are you all capturing with edit=on?

[dellsam34]

"Edit" should always be ON, What it does is it turns off all image processing when copying video tapes to another deck back in the day, Capturing is no different from copying to another VCR, "Edit" is the equivalence in audio of recording from the line out of a HiFi audio deck vs from headphone out with bass and treble are changed via an equalizer.

LTBC/DNR should always be ON unless the distortion outweighs the benefit, B.E.S.T should always be ON, It analyses the tape formulation characteristics and adjusts current to the video heads coils accordingly for an optimum signal output.

Any processing done by the VCR when "edit" is off can easily be achieved by the proc amp during capturing without having to worry about image distortion, just make sure you use the histogram so you don't clip the levels.

[lordsmurf]

EDIT disables one of the main reasons to own this deck -- the quality NR. So unless the tape or projects needs EDIT, in general, the NORM/AUTO is suggested. The 9500 is a bit more rudimentary on the NR, as is the 7500, so that can be the issue here. So this exact tape may need EDIT, but certainly not all tapes.

The TBC+DNR is a married function, so some % of NR is also in the TBC circuits.

R3 off = add halos, other noises

SUPERIMPOSE / OVERLAY / ONSCREEN = off

CALIBRATION = usually off for most models, actually incurs jitter at times

[lollo]

Thanks dellsam34 for your reply,

I always use B.E.S.T. on because the tapes I capture have been recorded with the same machine using B.E.S.T. on.

About TBC/DNR is always on in all my captures. I never had the need to turn it off.

Any processing done by the VCR when "edit" is off can easily be achieved by the proc amp during capturing

I think that the proc amp is not able to perform the NR done by the JVC, that is what makes these machines so good.

I used edit=off (and D3R=on as well) because I found in my experiments that it gives the best image, and I wanted to archive a capture that is at its best without restoration.
For collection reason I wish to have a capture that is very similar to dvb-s broadcat. And, believe it or not, a restored version is "better" and "different" than the original program, even if it comes from a s-vhs (probably the low bitrate and the low resolution used in the 90's in Italy for dvb-s broadcast is the reason).

I also build a "restored" version of it using AviSynth filtering, to be archived as well (4TB HD are not expensive today)

I ignored that what makes the image better (imo) is also introducing some artefact. Now I have to choose or re-capture with edit=on to have all variants. Never ending capture tasks

[lollo]

EDIT disables one of the main reasons to own this deck -- the quality NR.

I was writing that as well in my reply to dellsam34, you arrived first

So this exact tape may need EDIT, but certainly not all tapes.

I suspect all my tapes have same behaviour, but it only stays for 2 or 3 frames, so I can leave it

[lollo]

By the way, searching the web I found somebody else with a similar experience with a 9600. I will study that post. Interesting!

http://www.digitalfaq.com/forum/video-capture/9215-jvc-s9600-tbc.html#post57713

[dellsam34]

I think that the proc amp is not able to perform the NR done by the JVC, that is what makes these machines so good.

I don't know what NR you guys are you talking about, The DNR is tight to the line TBC, There no other noise reduction other than that, at least for my model HR-S7600AM, Maybe JVC made different configurations for different models, Hence my VCR doesn't have "calibration" feature. Edit delivers the raw RF signal to the Y/C board as it is on tape with no processing other than DNR, You should never be capturing with EDIT off in my opinion.

[lollo]

I don't know what NR you guys are you talking about

From some old post, concerning 9500 and 9600:

JVC has multiple image filters in use:
- one set is tied to the TBC, primarily the temporal NR (off only if TBC is off)
- EDIT turns off another set of the filters, primarily the in-frame NR and Chroma NR

I know nothing about HR-S7600AM

[dellsam34]

JVC has multiple image filters in use:
- one set is tied to the TBC, primarily the temporal NR (off only if TBC is off)
- EDIT turns off another set of the filters, primarily the in-frame NR and Chroma NR

I know nothing about HR-S7600AM

Is there a tech bulletin showing this, In my VCR I can only remove the chroma noise with TBC/DNR ON, no other function will remove that nasty blue and red static.

[lollo]

Is there a tech bulletin showing this

I do not have such, I reported comments from other users.

I have only my experiments where I interleave the results of UtoY() and VtoY() for the different options.

Attached a sample (HuffYUV, can be seen frame-by-frame with VirtualDub)

[oln]

Is there a tech bulletin showing this, In my VCR I can only remove the chroma noise with TBC/DNR ON, no other function will remove that nasty blue and red static.

There is this tech thing describing new features in the HR-S9500 and other models in the 1998 lineup. (also attached a version in case that link goes away.) It doesn't mention EDIT specifically though.

There is noise reduction both in the main video IC (analog), though other than a comb filter I think it's only for Y. The TBC/DNR/SVHS board has additional chroma noise reduction, including 3D noise reduction which looks for changes between frames. I suspect that's what you are seeing the effect of here, I don't think a more simple analog filter would do inter-field noise reduction.

EDIT does at least turn off all or most of the analog NR in the main video IC. It does not turn off the digital NR when TBC is on from what I've seen, but it's possible it adjusts it.

The technical manual seems to indicate that there is some digital noise reduction going on even if the TBC is disabled. Though I've noted the same as you with it off, that it doesn't reduce chroma noise much if the TBC is off.

JVC shared the main video ic between SVHS and higher-end non-SVHS models, but only the SVHS ones have the digital boards (non-TBC ones have a "2D digital" board.) which include Chroma NR judging by the schematics. Additionally there are a handful of hi-fi models in later gens like the HR-DD868 that has an extra chroma NR board according to the manual for that one, though the base video IC does not seem to have it. Most manufacturers seem stopped including the Chroma NR part of VHS HQ in the early 90s other than on Super VHS and a few high-end standard VHS decks.

On the 9500E I have I prefer to enable EDIT as things otherwise get a overly soft but YMMV. The HR-J658EH I have is also a little on the soft end (but that lacks EDIT mode). JVC added the extra picture settings in the next years models (such as the 7600), even in the non-SVHS decks, which is pretty neat. The B.E.S.T / video calibration feature also seems to have some impact on sharpness and noise reduction setting but I have not found the older technical manual referenced in the attached one that describes how that feature works.

[dellsam34]

So that explains the reason for "EDIT" to exist in the high end models, It disables all analog processing that alter the original signal. Honestly, I would rather use a script than a baked in feature in the master file.

[lordsmurf]

By the way, searching the web I found somebody else with a similar experience with a 9600. I will study that post. Interesting!

You must remember behavior can vary model to model, and even unit to unit (due to age, errors, or production run). Each has slightly different properties. I've never really delved deep into cataloguing these, but I know many for NTSC. Some of PAL.

Maybe JVC made different configurations for different models

Correct.

, Hence my VCR doesn't have "calibration" feature.

Calibration isn't NR.

It disables all analog processing

Not all. Some % of NR is required for a VCR to function.

that alter the original signal.

This is misleading. The "original signal" is a chaotic mess. Processing is required to make it watchable. That's just how VHS works.

Honestly, I would rather use a script than a baked in feature in the master file.

Some errors cannot be fixed post-VCR, or post-analog (pre-capture). You cannot script away every problem.

The technical manual seems to indicate that there is some digital noise reduction going on even if the TBC is disabled.

Example: DOC

[lollo]

The TBC/DNR/SVHS board has additional chroma noise reduction, including 3D noise reduction which looks for changes between frames. I suspect that's what you are seeing the effect of here, I don't think a more simple analog filter would do inter-field noise reduction.

I agree, because I noticed this effect only at scene change (but could also be hidden somewhere else).
Another suspect I had is that there was some light ghosting in the original video that is enhanced by the JVC filtering, but looking at the same video digitally "captured" from a dvb-s dump I did not see it.

The B.E.S.T / video calibration feature also seems to have some impact on sharpness and noise reduction

Yes, I confirm. I thought it was only a "tracking helper" but it is not the case.

However, the only setting causing the "ghosting" is non edit mode. I tested all 8 possible combinations of B.E.S.T. on/off + edit on/off + D3R on/off (DTBC/NR is always on).
Attached the results.

B.E.S.T. on

[Attachment 57991 - Click to enlarge]

B.E.S.T. off

[Attachment 57992 - Click to enlarge]

You must remember behavior can vary model to model, and even unit to unit (due to age, errors, or production run). Each has slightly different properties.

Understood

[oln]

It disables all analog processing

Not all. Some % of NR is required for a VCR to function.

I haven't found any datasheets for the JVC chips, but in e.g this one for the TDA9725 (used in Panasonic NV-HD620, 630 and related models, though I don't think any of them actually let you put it into EDIT) shows the difference between the EDIT setting of the chip and normal mode:

[Attachment 57993 - Click to enlarge]
It won't disable all analog processing, e.g de-emphasis is kind of required otherwise the image would not look right at all. It seems to turn off or severely reduce YNR (chip does not feature CNR), and turn off sharpness adjustment.
This datasheet for the AN3501NFBP shows something similar. As far as I know the main idea is to reduce generational effects when dubbing tapes. E.g if dubbing you want to avoid sharpness adjustment ending up on the copy, and it then being sharpened again when playing back the dubbed tape.

The video ICs from Sanyo used in a lot of VCRs (e.g LA71750EM) don't mention any EDIT mode, so it may also be up to the VCR what an EDIT mode entails. On newer ICs like in these JVCs the chip settings are adjusted digitally over I2c or similar rather than by adjusting pin voltages, so the system control could be programmed to set things however it wants.

[dellsam34]

Not all. Some % of NR is required for a VCR to function.

Chroma and luma filtering, de-emphasis and other processes required to shape the RF signal are not what we are discussing here, We are talking about menu items that can be turned on and off by the user.

[lollo]

An addition to the discussion

I found somebody else (third case) in the forum who experienced the same behaviour https://forum.videohelp.com/threads/395451-Chroma-mess

I am starting to suspect that it can be a common characteristic of PAL JVC HR-S9500/HR-S9600 machines (temporal filtering)

I really do not wish to change my setting to edit=on (in my case the video is really better with edit=off), but in the post I linked the ghosting stays for 6 frames, which is too much imo, and I do not want bad surprises for the next captures. Decision taken

[KarMa]

I really do not wish to change my setting to edit=on (in my case the video is really better with edit=off), but in the post I linked the ghosting stays for 6 frames, which is too much imo, and I do not want bad surprises for the next captures. Decision taken

EDIT=OFF uses temporal denoising on the Chroma, which will cause color to be smeared across multiple frames, most obvious during scene changes.

I once took the advice here to have EDIT=OFF when I first got into this. That was a mistake and have been using EDIT=ON for the past +5 years.

Old test samples. https://drive.google.com/drive/folders/160NS3pfAW6v-pRl6fOCYmk9hjddPxuGS

[lollo]

Thanks for your contribution!

EDIT=OFF uses temporal denoising on the Chroma

That's why I wanted edit=off, because the overall video is better in my case. Unfortunately, at scene changes it produces this ghosting artefact.

Originally, I did not plan a restoration of all my captures, and then I wanted the best picture to be captured (edit=off).

It is true that at a standard play the defect is not visible in my case, so I can leave everything as it is, but starting from now I will adhere to the "edit=on and restoration= always" family

Just for curiosity, did you experienced the ghosting on NTSC JVC machines?

[KarMa]

Just for curiosity, did you experienced the ghosting on NTSC JVC machines?

Yes.

[Brad]

I found somebody else (third case) in the forum who experienced the same behaviour https://forum.videohelp.com/threads/395451-Chroma-mess

I am starting to suspect that it can be a common characteristic of PAL JVC HR-S9500/HR-S9600 machines (temporal filtering)

Quoting myself from that thread:

My analysis of (US NTSC) JVC S-VHS settings based on samples posted by someone else: http://www.digitalfaq.com/forum/video-capture/8455-comparing-jvc-vcr.html#post64723

Specific VCR there is JVC SR-VS30U. Other models may differ a bit.

There are no shot changes in the sample posted there, so I may have been a bit hasty to say that "there is no luma NR" for EDIT + TBC/NR.

The behaviour for PAL models is either identical or very close to it, as I recall. The user FLP347 has posted many samples in multiple threads comparing various settings and workflows for PAL VHS and 8mm.

This is just one of his big threads:
https://forum.videohelp.com/threads/376945-Conventional-analog-capture-workflow-vs-alt...ods-comparison

[lollo]

Thanks for your reply.

BTW, msgohan = Brad (Formerly vaporeon800)!!! Wow, I did not know. Thanks for all your contributions in VH and DF, then, highly appreciated!

[Brad]

No problem. I'm glad you've found some of my posts useful.

I'd change my username on DFAQ too if I could; ah well.

I've sent you a PM about a post in another thread.

[lollo]

An update to the topic, maybe useful for future readers.

Unfortunately the setting EDIT=on is not able to completely remove the "frame blending" at scene changes in all cases.

In this sample it works quite well, and the artefact is almost completely removed:


[Attachment 58842 - Click to enlarge]


[Attachment 58843 - Click to enlarge]

In this other sample the artefact is only reduced a little bit:


[Attachment 58844 - Click to enlarge]


[Attachment 58845 - Click to enlarge]

same sample, other time:


[Attachment 58846 - Click to enlarge]


[Attachment 58847 - Click to enlarge]

When I check the effect of luma noise reduction and the chroma noise reduction, I have the impression that the setting EDIT=on only disables (or reduces) the luma noise reduction, as shown in bottom part of the pictures with the 3 planes. The artefact is present on the U and V channels.

On the other hand, I am not sure that a display using avisynth GrayScale() command only shows the luma vithout chroma contamination (I have not avisynth plus installed to use ExtractY() command). If anybody can confirm the result of GrayScale() command it will be helpful.

In summary, EDIT=on almost removes the artefact in some cases, only reduces it in other cases. To remove or further reduce the "blending" contamination I think that also the Digital TBC/N.R should be disabled; this is not an option for me, beeing it the main reason for the JVC to produce a nice and (more important) stable image.

[dellsam34]

I wouldn't worry about the frame blending if it's a frame or two, Our brain retain that information anyway even if it is not there.

[lollo]

It is up to 4/5 frames sometimes. I rely on my brain to retain more because it's 50 years old, so I won't notice the defect