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Old 20th March 2015, 07:45   #1979  |  Link
LouieChuckyMerry
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Quote:
Originally Posted by hello_hello View Post
Something else to try for really noisy sources. Aside from increasing the denoising a little, I sometimes use a faster speed preset. The logic being if not all the noise is removed, QTGMC tends to "stabilise" the noise that remains and static noise doesn't look natural. Using a faster speed preset can sometimes help it to look more natural as it doesn't "stabilise" as much.

QTGMC(InputType=1, Preset="Medium", EzDenoise=2)

And if the noise removal results in colour banding try adding gradfun3() to the end of the script. You'll need the Dither package for that.
http://forum.doom9.org/showthread.ph...59#post1386559
I've added this to my presets and will check it out ASAP, thanks.


Quote:
Originally Posted by hello_hello View Post
I do use SMDegrain myself, but mostly only on "clean" video. By "clean" I mean where the picture is nice and stable but where there might be excessive grain. When the underlying picture isn't "stable" or there's compression artefacts then I'd mostly use QTGMC in progressive mode instead.
I think that SMDegrain is brilliant, finding that "SMDegrain(Lsb=True,Chroma=True,Plane=0)" works wonders and raising the thSAD from the default (400) to 600 or 800 for extremely grainy (usually older movies shot on film) sources. I'm really curious to try your above script and compare because QTGMC seems to run about 50% faster on my rig. What do you mean by "stable" in reference to the picture?


Quote:
Originally Posted by hello_hello View Post
NTSC "video" is 29.970fps (either interlaced or progressive). If something's purely 29.970fps interlaced, then deinterlacing to 29.970fps progressive (or 59.940fps progressive is usually better) would be the way to do it.
"Film" converted to NTSC is originally 23.976fps converted to 29.970fps using telecine. Technically, applying inverse telecine (IVTC) probably isn't de-interlacing as such, but it usually falls under the "de-interlacing" category in most encoder GUIs. IVTC restores the original progressive frames (at 23.976fps).
http://en.wikipedia.org/wiki/Three-two_pull_down

I assume when MeGUI analysed the video it decided it was a hybrid. Partly "video" (29.970fps), but mostly "film" (originally 23.976fps).
The "film" parts would have IVTC applied and the "video" parts are de-interlaced and converted from 29.970fps to 23.976fps by dropping frames and using frame blending. The latter isn't necessarily ideal but you get a constant 23.976fps.
When I suggested IVTC earlier I just selected "Film" in MeGUI's de-interlacing section manually, and copied what was added to the script. That'd assume the entire thing was "film" (originally 23.976fps). Chances are it is entirely "film", in which case the result would be the same.

Anyway, while you can de-interlace "film" it's usually better to apply IVTC to restore the original progressive frames rather than apply de-interlacing, which doesn't. A 3/2 pattern of clean/dirty frames (where there's constant motion) indicates IVTC should be applied. Deinterlacing telecined "film" results in a type of frame blending which doesn't look nice. For your sample, where most frames are repeated, you might get away with de-interlacing but I still think it'd be better to reverse the telecine process to output progressive 23.976fps instead.
Hopefully all that makes sense.....
I only had to read this, slowly, a half dozen times to have an understanding ;-) . Seriously, thanks for the explanation, I really appreciate it.
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