Laserdisc composite deinterlacing upscaling and comb filter?

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Fudoh
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Re: Laserdisc composite deinterlacing upscaling and comb fil

Post by Fudoh »

Notch filter on right side clearly is better.
I don't disagree based on your snapshots, but it sounds like a harsh generalisation. Especially when I see an image comparable to your right column on my setup.

As you said yourself, on the signal's way to the display (or panel) it has to run through a luma/chroma seperation process at some point. And the discussion on how and where this is done best, isn't exactly new. Enough people tried to find their optimal setups for ages.

It's also pretty common knowledge that not all CFs work well with LD content. Hell, even Pioneer totally messed up some of the CFs in their players. And this doesn't neccessarily only apply to low-end machines. The X9's CF for example is completely unusable.

My results using a Pioneer DVR as a CF are really good. And the player quality isn't this important. I currently have a S9 and a X9, but I had cheaper players before and they all looked fantastic when run through the Pio DVR.
Generally the best comb filters are probably 2D Faroudja, Extron, Crystallio, etc.
But with laserdisc it's going to require a different C.F. besides the standard type.
Which Extron do you have in mind? The Faroudja isn't great. The CII is good, but it binds you to the processors video processing (deinterlacing, scaling) after all.
Thought I saw some D.I.Y. schematics for cvbs notch filters.
I think unless you can point to an available end user product which performs a better job than the CII's or the Pio DVR's CFs, then it's a bold statement to say "Stay away fromb comb filters with laserdisc!" Maybe we can agree on a "beware of using the wrong CFs with laserdisc" instead?
Last edited by Fudoh on Fri Sep 21, 2018 12:35 am, edited 1 time in total.
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orange808
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Re: Laserdisc composite deinterlacing upscaling and comb fil

Post by orange808 »

The Kramer FC-10 comb filter isn't a great comb filter.

I think your first clue would be how easy and cheap the FC-10 is. You can't even give one away. If you offered it to me free of charge (you paid shipping), I would still decline.

In my own personal opinion, the FC-10 is one of the wrong comb filters.
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Fudoh
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Re: Laserdisc composite deinterlacing upscaling and comb fil

Post by Fudoh »

In my own personal opinion, the FC-10 is one of the wrong comb filters.
but maybe it's not per se the CF's fault. I never used the Kramer one, but when you look at those snapshots, then the Kramer obviously adds a lot of bad edge enhancement. But don't think that's really tied to the luma/chroma seperation process - it's more likely just a bad design of the unit.
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Steamflogger Boss
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Re: Laserdisc composite deinterlacing upscaling and comb fil

Post by Steamflogger Boss »

orange808 wrote:I think your first clue would be how easy and cheap the FC-10 is. You can't even give one away. If you offered it to me free of charge (you paid shipping), I would still decline.
Exactly. These cheap comb filters aren't really good for anything now and there is a reason they are cheap. I've tried a few different ones to very middling results. Most things old things that are very high quality are well known as such now, and typically cost accordingly.

So if the whole point from this poster was just that the now $5 Kramer comb filter isn't good I would agree with that but it is hardly newsworthy to begin with.
holering
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Re: Laserdisc composite deinterlacing upscaling and comb fil

Post by holering »

Here's the comparison shots with the Panasonic DMR_ES10 + PVR150 (cvbs using 5-line 2D combing (no notch filter) and +50% color saturation. CVBS and SVIDEO: agc+chroma agc off, spatial-temporal filters off and hm12 to ffvhuff to png.):

Svideo left | cvbs right
Image
Notice there isn't really any corrupt luminance or halos on the cvbs side. Chroma might be offset +1 to the right on cvbs (and possibly svideo)

This's the same Mermaid LD through the DMR-ES10 with the same PVR150 and settings as above. The LD was filtered through each picture setting (soft, fine and normal) which supposedly is the comb-filter settings (I forgot the cinema setting but it has the same problem).

Soft left | normal right
Image
Same corrupt frequency as the Kramer FC-10D


Same thing with Mermaid LD again (with same settings), but this time comparing the DMR-ES10 "FINE" setting with a JVC SVHS HR-S7300U.
JVC SVHS HR-S7300U with same PVR-150 and svideo settings left | Fine right
Image
Even though this's one of the most basic SVHS decks, the resulting image still suffers corrupt luminance, and the "FINE" setting from the DMR-ES10 still has the same problem.


Here's another example from a different user with RF with cable service
Image
Lots of halos. This time with Broadcast air service.

Another similar example but this one actually seems to improve with the comb filter from pvr-250 vs pvr-150 falling to notch filter from comb errors. This might be, because it's a digital service?
pvr-250 top | pvr-150 bottom
Image
Bottom certainly looks worse but perhaps this is due to the different frequency from the source...?

Just want to add I might start a new thread about the PVR-150 with linux. I have settings in scripts for changing the hardware to useful settings (notch filter mode for LD and gaming, no agc or chroma agc, 5-line combing, and examples for dumping to FFVhuff real-time). The results with notch filter are way better with RF sources like NES, Genesis and Dreamcast. What's interesting is you can buy the USB version for $12.00 used; specifically the WinTV PVR USB2 (very similar to other USB Wintv devices except this says PVR in the name with USB2 and it's round). With the USB version having the cx2584x chip, you could probably attach a minimal virtual machine (net-based debian, gentoo, custom D.S.L. etc) for dumping video while using Windows for other tasks.
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