Troubleshooting AVISource open failure / couldn't open file
 

This error message will come up if you don't have exactly the proper path or filename for the .VDR file, so first things first, make absolutely sure you've got that part right.

When you're creating the signpost file in VirtualDub, it asks about two different filenames. The first is just a name unique to the frameserving engine itself. It defaults to be the same as the source file, something like "050729190042.mpg". You can actually put in whatever you want there as long as it's a unique name compared with anything else also being frame served on the system. Heck, you could call that part "testing.123" and it would work.

The second filename is the important one where it asks for the actual .VDR file being saved. And that's the part that matters for the AVISynth script. So if you put in "C:\test.vdr" then your AVISynth script should be:

AVISource("c:\test.vdr").AssumeTFF().SeparateFields()

Once you've started the frame server, nowhere in the little VirtualDub frameserving window do you see the actual VDR filename itself, but it's really listening for any reference being made to that .VDR file and spouting out the appropriate AVI type information, fooling the other app into thinking it's a real AVI file sitting on the disk. (Hope that all makes sense!)

If you're absolutely, absolutely sure that you've got the right path and filename then there's some strange things happening with your AVISource filter. You can alternatively try changing "AVISource" to "AVIFileSource". But I think it actually uses the same call with either one. Using "OpenDMLSource" or "DirectShowSource" should not actually work for stuff being frame served from VirtualDub, but you can try it. Those work just fine with other AVI files, but not VDR stuff.

Another option is to see if you've got the newest stable version of AVISynth, which at the moment is available on SourceForge here:

http://sourceforge.net/project/showf...ckage_id=72557

Hope this helps. Let me know if you still have issues!

-Lorin

thanks for your reply, i will try it again

Lorin,

I'm talking about a motorized mount. Please find the details in the link below. Thanks for your interest.

http://www.dvinfo.net/conf/showthread.php?t=48563

Lorin, what you've posted is really useful, the 1080i to 720p page caught my attention. What I'm wondering is do you know of a way in vDub to rescale from 1080i to 576i/480i, ie standard def, retaining the normal field signature of the original interlace footage?

What I'm thinking is for editing HDV footage offline at DV quality which would mean we can use our existing DV cardesand monitors for offline editing before going to online. However the process I've worked out to so far only works for non-interlaced footage (with the Z1Us that means CF25 which I know is not really progressive but can be treated as if it was by VirtualDub.)

Filter to get to 4:2:2 NTSC or PAL
 

You can use this AVISynth script now, but it compromises the vertical resolution slightly. Still works pretty well:

x=AviSource("C:\frameServe.vdr").AssumeTFF().SeparateFields()
Interleave(x.SelectEven().BicubicResize(960,480).Crop(120,1,-120,0),x.SelectOdd().BicubicResize(960,480).Crop(120,0,-120,-1))
BicubicResize(720,240).ComplementParity().Weave()

This is to be used with an MPG opened with VirtualDubMod and then frame served.

A better option is a payware VirtualDub filter I'm working on now for that exact purpose. The goal is to retain all the resolution possible while also maintaining perfect interlacing. The result is better than DV because the color space ends up at around 4:2:2.

Beta will be available soon that adds a small logo in the lower right, and the payware version will go for $20. It's very straightforward because you can just open the MPG and drop this filter in, getting 4:2:2 standard def in one of these three formats:

* cropped
* letterboxed
* anamorphic

Any DV filter or tool can be used from there in the workflow.

I'll keep ya posted.

-Lorin

Thanks Lorin, Keep us posted on the plug-in, I'll be looking out for the PAL version.

Filters - Resize - Check interlaced box.

I've tried this but it always seems to mung the fields up, it doesn't seem very reliable and when it does seem to do it there is an unnacceptable jitter on screen.

What would be really great is if someone could come up with an internal bob deinterlace filter for vDub and a weave re-interlacer.

Lorin, would there be the possibility of some sort of academic license for your filter?

Definitely does. The bob effect is why I had started down this road. The AVISynth script I provided will work in that it doesn't botch the fields, creating that bob effect. But (as the VirtualDub and other resize filters do) it compromises on vertical resolution. Hence the reason for this filter, intended for those people out there like myself who are perfectionists when it comes to video conversion. Since the destination (SD) has comparatively much fewer pixels, every pixel counts and must be properly calculated.


I hope that $20 is affordable, but am willing to extend a $10 version for those buying 10 or more, hoping that would benefit those using it in a classroom setting. Those bulk licenses, while transferrable, would have to remain property of one organization and not resold individually.

Those purchasing the filter would be entitled to any future enhancements of that core functionality. I have on the radar for instance an enhancement to convert 1080i to 720p. Not feasible inside of VirtualDub itself due to the filter architecture there, but it could be set up as a standalone frameserver product or in other environments such as Avid and Premiere. But that is coming down the road.

My apologies to Chris if this goes overboard in terms of marketing a product in a newsgroup post. I'm hoping that by posting the AVISynth script solution that there is still merit in keeping this content!

-Lorin

Give this a shot and let us know if it works for you.

Video - Filters - ViewFields - Resize - UnViewFields

For Viewfields and UnViewFields
http://www.geocities.com/siwalters_uk/fnews.html

And when you check "Interlaced" on resize, which resize filter are you using?

Kyle,

It's wierd, but checking the interlace box seems to work now. I don't understand it, DV clips that yesterday had misaligned fields, today are playing perfectly well. I can only assume that the matrox cards are somehow automatically interpreting the fields in random ways (which is worrying but no fault of VirtualDub)

I gave it another go and was going to try using swap fields and such (which hadn't worked before), but now, a basic bicubic =-100 resize does the trick, with no noticable bob effect, though I should make it clear I'm watching on the university's rather impecunious set up, (ie cheap combo TVs instead of broadcast monitors for viewing PAL output) but what I did pick up was a noticable softening. I saw the same softening when I resized CF25 material, a frame resize was sharper (rather too sharp in fact with noticable aliasing) than an interlaced scale, though in both cases you'd end up with a progressive image.

I have to say I get very nervous when problems fix themselves, I never know when they'll decide to get unfixed again.

I'll try the view/unview fields filter and see what difference that makes, certainly it looks good from the test I've done on my office desktop.

Thanks Kyle.

Glad it works for you now.

Bicubic and Bilinear will give a softer picture. Try a comparison between those and Lanczos3. You should find Lanczos to be much sharper. See if that gives the effect you are looking for.