25i -> 50p De-interlacing

[zilog jones]

Are there any AviSynth filters that do this nicely, like some of the ones in DScaler? The only ones I've come across, like DGBob and TDeint, halve the vertical resolution - the ones on DScaler don't do this somehow.

[scharfis_brain]

the deinterlacers of dscaler are halving the resolution, too!

But it is not THAT obvious like when you look your tdeint-ed or dgbobbed frames with non-realtime.

[HardyG6]

DGBob halving the resolution? What exactly do you mean?
As far as I noticed, it interpolates the missing lines and so keeps full resolution (Video format, of course the video quality is still half height or a bit better. But missing infomation is missing information.)

Here is the script I use for creating non-interlaced 50fps videos, using my digital TV recordings as the source:

LoadPlugin ("c:\programme\avisynth 2.5\plugins\dgbob.dll")
LoadPlugin("c:\programme\avisynth 2.5\plugins\MPEGDecoder.dll")

MPEGSource("d:\test.mpg")
#AVISource("d:\test.avi")
#DirectShowSource("d:\test.mpg",fps=25) ## (causes trouble - doubles video speed)

DGBob(order=1,mode=1,thresh=12,ap=false)
Lanczos4Resize(720,576)

[Mug Funky]

tdeint matches everything that can be matched - it'll keep as much resolution as you can reasonably expect such a deinterlacer to keep.

the best way to improve vertical resolution from here is by motion-compensation, but that's not perfect yet (it's pretty damn close...).

[zilog jones]

On closer inspection, when I use "Video (Greedy High/Low Motion)" in DScaler, it most certainly give 50fps video with 576 lines, but on fast moving parts it seems to do field bobbing or weaving or something. Here's a very bad example (courtesy of a 6m composite cable... not good!):

http://www.skynet.ie/~zilog/pics/dscaler.jpg

If you look at the text you'll notice there's definate 1-pixel-high lines, but with the moving stuff it looks a bit weird. Things like DGBob and TDeint would bob the entire screen, making that text barely legible, not to mention the flickering of typical bob deinterlacers, which is not apparent with some of the ones on DScaler. Is this motion compensation? And is there anything similar available for AviSynth?

There's also "Video Deinterlace (2-frame and Weave)" which seem to only deinterlace moving parts.

There's some explanation of how these work in the help file of DScaler. A lot of them seem to use combinations of deinterlacing methods.

[scharfis_brain]

did you ever played back a tdeint-ed or dgbobbed

video in realtime?

the flicker won't be THAT noticeable, like when stepping frame by frame through the video.

dscalers filters to flicker, too.
no doubt on that.
but it isn't visible that much due to realtime playback.

btw: you sample pic shows heavy metric misbehaviours of the choosen deinterlacer (threshold is too high)

[zilog jones]

I didn't change any of the settings, and as I said it's a very bad example as it was the only interlaced video with any movement I could find (and coincidentally it's the worst-looking channel on cable!). And I still fail to see any flickering at all on stationary parts of the picture on the 2-frame and greedy de-interlacers. I know the flickering isn't as noticable with bob de-interlacers when playing, but they're still there.