Combing in Deinterlaced Video

[unluckyfridays]

I wanted to make an encode of this DVD I have so I used makemkv to make the segments on the DVD into mkv files. There seems to be one file that behaves differently than the rest. I see combing on the video and alot of it on very high motion scenes, it's weird because the other segments on the DVD dont have combing like this I will provide the mkv file makmkv made from the source DVD which I own. I wanted to deinterlace it plus encode to x256 for plex streaming but the combing is really severe even on the deinterlaced encode. I tried using xmediarecode and hybrid. The combing is mostly visible during transitions and high motion scenes. Also it doesnt happen on every scene just every so often. I was wondering if the material is telecined but I'm not sure how to tell, tried counting the frames but I feel like I'm doing that wrong.

original source file [from DVD] = http://drive.google.com/file/d/1wsjlrg4yy3BNUt0aeonyv_9z9wZPs05j/view?usp=sharing

Here are some pictures to show the combing I'm describing

[Attachment 65835 - Click to enlarge]

[rrats]

Some idiot resized video before autoring the DVD

[jagabo]

It was also hard telecined from 25p before the resizing. You could blur the two fields together and decimate back to 25p. That will nearly eliminate the combing (those frames will look like double exposures though) but you will lose some vertical resolution.

Mpeg2Source("title_t02.d2v", Info=3) 
TFM(pp=0)
BilinearResize(width, height/2).Spline36Resize(width,height)
TDecimate(mode=2, rate=25.0) # or TDecimate(Cycle=6, CycleR=1) to get 24.975 fps

It would also be possible to only blur the frames with residual combing after TFM. But that may be more jarring as some parts of the video would switch back and forth between sharp and blurry ever few frames.

[unluckyfridays]

this looks really well thank you so much, I was looking for this kind of input because I had a feeling it was telecined just didnt know how to go about from there.

[jagabo]

I worked out a way to blur only the frames with screwed up interlacing:

Mpeg2Source("title_t02.d2v", Info=3) 

decombed = TFM(pp=0)
blurred = decombed.BilinearResize(width, height/2).Spline36Resize(width,height)
testclip = decombed.Sharpen(0.0, 1.0) # enhance any residual combing

ConditionalFilter(testclip, blurred.Subtitle("B"), decombed, "IsCombedTIVTC(6)")

TDecimate(mode=2, rate=25.0) # or TDecimate(Cycle=6, CycleR=1)

Some frames are needlessly blurred because they have compression artifacts that look like combing to IsCombedTIVTC(). Some frames have very mild residual combing and get through without being blurred. You can increase the threshold value to get fewer false positives (ie, fewer blurred frames) but then more frames with mild combing will get through. Conversely, you can lower the threshold value and get more false positives and fewer combed frames. Pick a value that suits you. The Subtitle("B") is there to make it easier to see when the blurred frames are substituted. Remove it before your final encoding.

[unluckyfridays]

fascinating that you were able to fix it up this much, I actually just got avisynth all setup and tried out the script you posted before this new one.

[unluckyfridays]

I worked out a way to blur only the frames with screwed up interlacing:

Mpeg2Source("title_t02.d2v", Info=3) 

decombed = TFM(pp=0)
blurred = decombed.BilinearResize(width, height/2).Spline36Resize(width,height)
testclip = decombed.Sharpen(0.0, 1.0) # enhance any residual combing

ConditionalFilter(testclip, blurred.Subtitle("B"), decombed, "IsCombedTIVTC(6)")

TDecimate(mode=2, rate=25.0) # or TDecimate(Cycle=6, CycleR=1)

Some frames are needlessly blurred because they have compression artifacts that look like combing to IsCombedTIVTC(). Some frames have very mild residual combing and get through without being blurred. You can increase the threshold value to get fewer false positives (ie, fewer blurred frames) but then more frames with mild combing will get through. Conversely, you can lower the threshold value and get more false positives and fewer combed frames. Pick a value that suits you. The Subtitle("B") is there to make it easier to see when the blurred frames are substituted. Remove it before your final encoding.

Are you using any other filters because your output looks much more clear than mine, mine is a bit more blurred.

yours

[Attachment 65848 - Click to enlarge]

mine

[Attachment 65849 - Click to enlarge]

[unluckyfridays]

Disregard that last post, didn't see the sharpen on the script itself, thank you so much jagabo! this thread can now be closed, problem solved on my end.

[jagabo]

Note that the Sharpen(0.0, 1.0) isn't sharpening the picture you see. It's sharpening the picture that's used to determine if there is any combing in the frame. The vertical sharpening enhances the combing making it easier for IsCombedIVTC() to detect it. If combing is detected the blurred frame is used, if not, the unblurred frame is used.

[unluckyfridays]

Note that the Sharpen(0.0, 1.0) isn't sharpening the picture you see. It's sharpening the picture that's used to determine if there is any combing in the frame. The vertical sharpening enhances the combing making it easier for IsCombedIVTC() to detect it. If combing is detected the blurred frame is used, if not, the unblurred frame is used.

Yes in the case of that script it is, I just meant in the first video you shared it seemed more clear vs my blurry one. If you run the sharpen plugin by it self it should clear up the image a bit, correct? Only for the 1st script. The second one is kinda jarring like you said due to the blurry and non blurry frames.

[unluckyfridays]

Note that the Sharpen(0.0, 1.0) isn't sharpening the picture you see. It's sharpening the picture that's used to determine if there is any combing in the frame. The vertical sharpening enhances the combing making it easier for IsCombedIVTC() to detect it. If combing is detected the blurred frame is used, if not, the unblurred frame is used.

In the 1st script you posted did you use any other filters than the one you shared? because I used that script but your output looks much more clear than mine, notice in the pic I sent you can make out the background objects easier the lines on them. On mine they look smeared and blurry.

[jagabo]

Note that the Sharpen(0.0, 1.0) isn't sharpening the picture you see. It's sharpening the picture that's used to determine if there is any combing in the frame. The vertical sharpening enhances the combing making it easier for IsCombedIVTC() to detect it. If combing is detected the blurred frame is used, if not, the unblurred frame is used.

In the 1st script you posted did you use any other filters than the one you shared? because I used that script but your output looks much more clear than mine, notice in the pic I sent you can make out the background objects easier the lines on them. On mine they look smeared and blurry.

I'm pretty sure the picture in post #7 is from my second script (post #5). Note that the video sample I uploaded has the same name as the sample in my first reply (post #3). Both samples were made from their respective scripts.