Help with deinterlacing/processing PAL VHS tapes

[Stigma]

Hey,

Its been a while since I did any video editing, so im hoping someone can point me in the right direction.

I am converting the familys old PAL VHS tapes for PC use, so we can finally retire the old VHS and have the video more accessible for those old family tapes.

I capture the video from the VHS player via an easycap device that dumps it into a raw lossless format for me.

My main problem is the interlacing. How do I go about best deinterlacing this stuff so it looks decent on a computer monitor? Way back when I encoded anime DVDs I remember I allways shyed away from the PAL versions because I could never get around the severe ghosting caused by field blending - and I didnt know any better way to deinterlace PAL. However, I also just recently converted a bunch of PAL DV tapes, and getting those to progressive was a breeze - in fact adobe premieres encoder did it for me automatically, so i'm thinking if one is possible the other should be too right? I guess adobe just can't handle them automatically because there is no metadata in these files about field orders and such.

Whats the best way to go about doing this? Once I have a progressive video I think I can handle the rest of my own. I do remember a little of how avisyth worked, and I also have adobe premiere CS5 availiable if its easier that way.

Thanks so much in advance for any help :)
-Stigma

[Nightshiver]

Post a sample and we'll tell you.

[Stigma]

Post a sample and we'll tell you.

Sure thing! Please tell me how I should make the sample though. What format should it be in, and how much do you need to analyze it? I assume a compressed format should be ok for analysis too, but I feel its better just to ask and not assume too much :)

I should mention that I did expermiment a little with using the bob filter thing included in the latest version of vdub. That actually seemed to work decently well. The only problem with that is that once in a while (in no particular pattern that I can detect, about every 15-40 frames or so) I get a frame that seems to go one step backwards. This is when doubling it up to 50 frames. If not doubling and discarding one field instead it comes out as one frame that is identical to the last. In both cases its a bit annoying as it presents as a sort of weird stutter when you watch it in motion. I will try to include atleast one such in any sample I make for you.

I'm also not sure if this is the ideal way to do it (ie. if im on the right track at all) as it does throw away a lot of video info if I understand properly.

-Stigma

[Ghitulescu]

All camcorders that are PAL are actually PAL, ie TFF. No need for fancy algorithms to find the correct sequence. Don't confound this with IVTC, which doesn't exist in PAL.

[Nightshiver]

If you captured the footage into a lossless avi, all you need to do is cut part of that avi for us to view, ie using VirtualDub and then selecting no compression from the video menu in Vdub. We always want original sources and not encoded ones, so your lossless capture is what we want, albeit we only want a small sample.

[Stigma]

Sorry for not providing a sample yet. I have identified a flaw in my capturing of video that probably explains atleast the "backwards" stuttering problem I described. I want to iron out that bug before I submit samples for further help. No point in providing you guys with data that is allready flaws because of a bad capture.

Il bump the thread and provide a sample later if I get this fixed.

-Stigma

[2Bdecided]

My main problem is the interlacing. How do I go about best deinterlacing this stuff so it looks decent on a computer monitor?You leave it interlaced and use a player that deinterlaces on the fly.

Or else you deinterlace it all this year, find a better deinterlacer next year, deinterlace it again then, etc etc. Keeping both interlaced and deinterlaced footage to enable this.

If you must deinterlace, try tempgaussmc_alpha3 for quality. There's a far quicker tempgaussmc in a recent thread.

Far more important is a decent VCR containing a TBC, and a decent capture device. Starting with a standard VCR and a cheap capture device sounds like a recipe for mediocrity. And dropped/repeating frames! ;)

Cheers,
David.

[Floatingshed]

I agree. Keep the files as interlaced, (they will look artificially filmic if you de-interlace) play with a player that does the work on the fly. I.E. VLC with de-interlacing set to linear...

[Stigma]

Perhaps I will just keep a copy of the interlaced originals around, but I want to atleast make some deinterlaced versions as well. Deinterlacing on the fly is fine if it was for my own use, but this stuff is mostly for my parents and other familys use so it has to be as simple as possible - ie. click to play. I can't assume they even know what interlacing is, much less to use a player than can deinterlace on the fly.

Speaking of which btw:
- Does windows media player deinterlace?
and
- If so - does it need some sort of proper metadata in the file to let it know its interlaced or does it detect that from the frames themselves as it plays?

-Stigma

[Ghitulescu]

"Click to play" for non-technical people is to copy them directly to a DVD-recorder. You keep them interlaced, thus compatible at its most, everyone has one of these devices and BD players play them as well. Not to mention the computers. Any decent DVD-recorder should do better than cheap capture cards, if no pre/post-processing is needed.

If these are precious family memories, then you can go either for a good/better VCR + TBC + processing aids (chroma, noise etc.) or leave this job to a specialized lab.

[2Bdecided]

DVDs are simplest. Even PC DVD players deinterlace automatically on-the-fly by default. Unless you've disabled it. Though some are a a bit rubbish.

If your target is "click to play" PC playback not from DVD, then you need deinterlaced video. Probably square pixel. Probabably 25fps rather than 50fps (which means it won't look as good as the originals). And you need to figure out what codec, bitrate, resolution and media to use. This will all be a compromise and no way should this be your only copy of these precious family videos.

Good luck!

Cheers,
David.