strange QTGMC deinterlace error

[Srivas]

Hi.

I cannot understand. I'm trying to do a simple thing, deinterlacing video with qtgmc but then the output shows that the places with movement are not properly processed (wavy movements). But there's nothing complicated and how does Qtgmc not understand it? But since I do frameserve from Vegas, maybe that's the problem. When I frameserve to Megui and add the script:

AVISource()
AssumeFPS(25,1)
ConvertToYV12(matrix="PC.709", interlaced=true)
QTGMC(preset="slow")

I get this problem. Original file is Upper Field First AVC 25fps. But, when I render inside Vegas by x264vfw, then it comes out properly. Both by Bobbing the frames. (Anyway, the same error is there without bobbing). So maybe it's some kind of frameserving error?

Here is a rendered and original clips

[jagabo]

The only thing I see wrong in the rendered file is the field order. The original is TFF. The field order is probably being lost in the frame server and AviSynth assumes BFF when it's not specified. Add AssumeTFF() to your script before QTGMC().

[Srivas]

That solved it. So simple. Thanks!

[jagabo]

Note: I changed my post after viewing your encoded sample.

[Srivas]

Yes, all clear now.

[_Al_]

Yes, Vegas frame serves Vegas project properties, not clip properties, so as for using dmfs, project properties and clip properties must match.

So if two clips with different parameters (ar, field order, frame rate, resolution) are loaded into Vegas, using frame server is always a compromise. One has to make executive decision what project properties will be - what is going to be served and knowingly let Vegas calculate certain clips into different parameters. That could be counterproductive in case of frame rate mismatch especially. So there could be situation where dmfs is problematic to use. For example to let Vegas resize interlace footage and even worse to change frame rate at the same time could damage video. One has to know what actually is Vegas doing (difference between frame resample and disable frame resample if changing frame rate).

[jagabo]

Before I saw the rendered image I thought "wavy" meant something like the image in this post:

https://forum.videohelp.com/threads/341461-Best-deinterlacing-in-Vegas-pro?p=2128746&vi...=1#post2128746

That is from improperly resizing interlaced video.

[Srivas]

That makes it clearer, although it seems to be a fact that Field order gets lost since I did have project properties set correctly, that is TFF.

I say "wavy" since I don't the terminology proper... That is why I added the clip to make it clear what I meant.