Attempting to remove ghosting (motion blur) after blend deinterlace

[antoniu200]

Hello!

I have a big stack of videos that have been deinterlaced with some kind of blending (not sure whether frame or field) and that method created some annoying ghosting. I don't have the original interlaced files, which is why I'd like to try and see what can be done in this case. The videos are ripped from DVD. Below is attached a part of one video.

I'd prefer if the method of repair was in Hybrid, tool made by Selur. If that's not possible, other solutions will do too.

Thanks in advance!

[manono]

I don't see anything wrong with it. It's progressive with no blending. Some motion blur but that's about it, I think.

The next time you upload a DVD sample, please don't repackage it as an MKV. Cut it using DGIndex and upload the resulting M2V.

[jagabo]

Actually, there is some very light blending. It's most obvious in a shot near the end of the clip:


[Attachment 57743 - Click to enlarge]

You can see it to the left of the thin black instrument dangling down near the right of the frame. I don't see any easy way of eliminating it. I tried subtracting a small portion of then next frame but it didn't help much:

next = loop(2,0,0)
Overlay(last, next, mode="subtract", opacity=0.05).ColorYUV(gain_y=12, cont_u=12, cont_v=12)

[antoniu200]

I don't see anything wrong with it. It's progressive with no blending. Some motion blur but that's about it, I think.

The next time you upload a DVD sample, please don't repackage it as an MKV. Cut it using DGIndex and upload the resulting M2V.

It is indeed progressive, but Hybrid sees it as interlaced, top field first, and the original video recording was interlaced. So, it's definitely been deinterlaced with some kind of blend algorithm.

As for MKV, what difference would it make if I packaged the video as M2V? I am very confortable with avidemux, but I'm not sure how that could export as M2V.

Actually, there is some very light blending. It's most obvious in a shot near the end of the clip:

You can see it to the left of the thin black instrument dangling down near the right of the frame. I don't see any easy way of eliminating it. I tried subtracting a small portion of then next frame but it didn't help much:

next = loop(2,0,0)
Overlay(last, next, mode="subtract", opacity=0.05).ColorYUV(gain_y=12, cont_u=12, cont_v=12)

The blending can also be seen on more intense scenes. The movement is extremely blurry and looks just like a very high latency monitor.
For this particular clip, when the camera moves up the car, you can see how where it should be a completely white bar, it's actually fondly joined of lines of black (at the 7 second timestamp).

I tried using SRestore from Hybrid and it helped reduce the artifact a bit. However, it made movement pretty choppy.

[davexnet]

The main reason m2v/mpg is preferred is that it's easier to use DGindex/Mpeg2source for use in Avisynth
I usually open these kinds of files in Avidemux and save them as mpeg program stream

[jagabo]

And it's not simply a ghost, it's a ghost of an edge enhancement. My guess is this was caused by an improper noise reduction or blur/sharpen that was performed while the video was interlaced (probably out-of-phase PAL).

[manono]

It is indeed progressive, but Hybrid sees it as interlaced, top field first...

It was encoded as interlaced while the content is progressive. That's common for PAL DVDs.

...and the original video recording was interlaced.

Since you don't have the source DVD, how would you know that? I disagree. Phase-shifted, maybe, but not interlaced.

So, it's definitely been deinterlaced with some kind of blend algorithm.

I disagree again. It was never blend deinterlaced.

As for MKV, what difference would it make if I packaged the video as M2V?

It saves unnecessary work for those willing to help.

... but I'm not sure how that could export as M2V.

Open a VOB in DGIndex, use the [ and ] buttons to isolate an appropriate section and then File->Save Project and Demux Video. That will produce the M2V.

[antoniu200]

Since you don't have the source DVD, how would you know that? I disagree. Phase-shifted, maybe, but not interlaced.

When did I say I didn't have the source DVD? What I attached here is a pure DVD rip.

I suppose this was interlaced since, where there should be frozen frames, there are frozen fields. I'll attach 2 sources from different studios that confirm this. Also, this show was recorded in an era where Hi8 was very popular and was actually a good choice, since the creators never wanted the show to be released outside of TV.

I disagree again. It was never blend deinterlaced.

Please state your arguments and then I agree with you.

It saves unnecessary work for those willing to help.

Actually, I exported as MPG from Avidemux, as per original request, and the end file was less than .1 of a MB smaller than the MKV. I'll attach it too.

I don't really understand your intervention. None of this was any help, unless you want to give me a solution to my problem or expand on the subject of why the frozen field doesn't indicate interlaced recording.

[manono]

When did I say I didn't have the source DVD?

DVD or not, you're claiming - with no evidence at all - that the DVD was made from some sort of "interlaced" source:

I don't have the original interlaced files...

Frozen frames? Frozen fields?

Please state your arguments and then I agree with you.

If you knew what blend deinterlacing looked like, you wouldn't make the claim. There are none of the double images, ghosted images typical of blend deinterlacers. As jagabo well knows, what he pointed out didn't come from a blend deinterlacer. He says perhaps from an overstrong temporal cleaner, but that's a far cry from blend deinterlacing.

I don't really understand your intervention.

Facts matter. You're asking for help and the first step is in understanding what you have and that what you're claiming simply isn't true. And second, I suggested it might be just motion blur (jagabo says different) with the implication that you can't do anything (or not much) about it. And I suggest again, forget about it and enjoy the TV series. A little bit of investigation tells me this is an outstanding series. Why haven't we gotten it in the US?

[jagabo]

I agree, the "ghosting" in the video is not from any kind of blend deinterlace or field blending from a frame rate conversion. Here's a split screen image of one frame on the left and the next frame on the right:


[Attachment 57782 - Click to enlarge]

The camera is panning up here so the blurred roof of the car in the foreground is moving down the frame. You can clearly see the light "ghost" on the right half lines up with the edge of the wide light band on the left. And there's at least two generations of ghosting. A few frames later when the camera stops panning there are no ghosts -- so this isn't some real detail of the car.


[Attachment 57783 - Click to enlarge]

This ghosting points at a temporal noise reduction filter with a threshold. One can get similar results with TTempSmooth() in AviSynth. Something along the lines of:

TTempSmooth(maxr=2, strength=3, lthresh=20, cthresh=20, lmdiff=10, cmdiff=10)

Off the top of my head I don't see any easy way to undo this. I might think about it some more later.