How to fix an interlaced TV show that has been broadcasted de-interlaced?

[Jak14140]

Hi!

I am new to this forum so hopefully you guys can help me out with my problem.

I am from the UK, and I like to record one of my favourite TV shows called “Classic EastEnders”.

Unfortunately, for 3 years, the channel broadcasting the show made a huge ****-up. The show itself was and is Interlaced, but the channel, for some unknown reason, broadcasted it in Progressive. And so the result of this was the picture quality being messed up - with terrible motion blur (from where it has been de-interlaced.)

Eventually (3 years later!) the channel finally fixed the issue and are now broadcasting the show interlaced, so it looks normal again. But now I am left with tons of episodes that have motion blur/judder from where they had been incorrectly broadcasted in Progressive.

My question is what can I do to fix these messed up episodes? Is there a way to somehow convert the Progressive back to Interlaced? Surely there must be something I can do.

Any help and solution would be much appreciated.

[poisondeathray]

If the "terrible motion blur" was from blend deinterlacing, there is probably not much you can do to improve it.

If you post a sample, someone will have a look and provide some suggestions

[Jak14140]

https://forum.videohelp.com/attachment.php?attachmentid=85321&stc=1&d=1738791829

Here is an episode.

[Jak14140]

https://forum.videohelp.com/attachment.php?attachmentid=85321&stc=1&d=1738791829

[jagabo]

I don't see any blur from deinterlacing there. What blur there is appears to be true motion blur.

Motion blur:

[Attachment 85322 - Click to enlarge]

Blend deinterlace would look more like:

[Attachment 85323 - Click to enlarge]

[Jak14140]

It’s definitely deinterlaced. You can tell by the non-smooth motion.

[poisondeathray]

It’s definitely deinterlaced. You can tell by the non-smooth motion.

Yes deinterlaced, but not blend deinterlaced. The amount of blurring is within normal limits

If the non smooth motion is your primary complaint, you could interpolate frames to 50p using RIFE or similar. This synthesizes the "in-between" frames, giving you the "soap opera" look. Many TV's can do this on the fly. If you wanted to, you can re-interlace that, or leave it at 50p. The negatives are sometimes you get artifacts, and higher quality interpolation is slow in terms of processing speed

[davexnet]

A part of the problem seems to be that the file is marked interlaced.
When played back in mpc-hc, it pays back at 50 fps with every frame doubled (EDIT this was due to a setting in mpc-hc)

Using Avisynth/DGindex and treating it as progressive,
you can easily recover the 25 fps and perhaps clean it a little.

Or you can just use Restream to mark it as progressive

Second attempt:

[Jak14140]

Hi,

I downloaded the file but was the picture meant to be squished?

Is there definitely a noticeable difference with what you did to it?

[poisondeathray]

Here is a small section with motion cut from the larger sample, processed with rife

The motion is smoother, but notice the artifacts around the semi transparent channel logo, especially around 3 seconds when passing the railing.

There might be some better models to use for static semi transparent channel logos; or you could remove the channel logo before processing .

[Jak14140]

It’s definitely deinterlaced. You can tell by the non-smooth motion.

Yes deinterlaced, but not blend deinterlaced. The amount of blurring is within normal limits

If the non smooth motion is your primary complaint, you could interpolate frames to 50p using RIFE or similar. This synthesizes the "in-between" frames, giving you the "soap opera" look. Many TV's can do this on the fly. If you wanted to, you can re-interlace that, or leave it at 50p. The negatives are sometimes you get artifacts, and higher quality interpolation is slow in terms of processing speed

How do you re-interlace it?

[davexnet]

Hi,

I downloaded the file but was the picture meant to be squished?

Is there definitely a noticeable difference with what you did to it?

Probably depends on the player. At least it's marked as progressive resulting in (potentially) cleaner play back.

[Sharc]

How do you re-interlace it?

In Avisynth:

Separatefields()
SelectEvery(4,0,3)
weave()

[poisondeathray]

How do you re-interlace it?

Yes , re-interlace with avisynth as sharc posted above. You could do it with other programs such as ffmpeg with -vf tinterlace

You don't "gain" anything from reinterlacing a 50p content file . Reinterlacing from 50p means you throw away 1/2 the scan lines to create a "25i" version

e.g.
logo removal , rife 50p version, and a corresponding 25i re-interlaced version

[Jak14140]

Hi,

Sorry for the delay in replying.

I have never used AVISynth or anything like that before. I have it installed, but have no idea how to actually use it. Can you talk me through it?

So you're saying the solution to my problem is to first mark it as Progressive, then interpolate frames to 50p using AVISynth, then re-interlace it? I'm still a bit confused.

[jagabo]

Might as well start with the docs:

https://avisynthplus.readthedocs.io/en/latest/avisynthdoc/getting_started.html

I usually use VirtualDub2 to view/edit scripts but many people like to use avspmod.

[Jak14140]

I just tried to do the test clips using the instructions from the link you sent me, but when I open the avs test file in Windows Media Player, it comes up with a different video than what it says it should be.

The video I get is a black screen with "The script's return value was not a video clip, (Is the undefined value)." in red letters.

[jagabo]

Post the script you're trying to open. Did you try the simple "version" script in the guide? What did it show? I didn't think WMP can display AVS scripts.

[jagabo]

Also try using Avisynth Info Tool to verify your AviSynth installation.
https://www.videohelp.com/software/Avisynth-Info-Tool

[Jak14140]

I’ve been doing some thinking, and am wondering if whether the easier solution to the motion problem is to simply buy a new TV?
The thing is, my current TV is a standard 50Hz Panasonic TX-L19XM6B, which is quite old and isn’t even a smart tv. It also has no motion interpolation settings.

Would a TV with a higher refresh rate (i.e 100Hz), do the job of ‘fixing’ the de-interlacing and make it look normal again? Or would the answer be to stick with a 50Hz TV but be sure to get one that has motion/frame interpolation settings, on the assumption that that will do the trick?

[jagabo]

Would a TV with a higher refresh rate (i.e 100Hz), do the job of ‘fixing’ the de-interlacing and make it look normal again?

No.

Or would the answer be to stick with a 50Hz TV but be sure to get one that has motion/frame interpolation settings, on the assumption that that will do the trick?

Yes. As noted, it often leads to weird artifacts. But at least those artifacts aren't permanently baked into the video itself.

[Jak14140]

But if course the potential issue of getting a new bigger TV is that the bigger the screen the worse the overall picture is going to look, right?
My current TV is a 19 inch, so I preferably wouldn’t want to go any higher than 24 or 30, because I’m just worried that by getting a larger TV it’ll end up making these shows look even worse.

Is there even such thing as a 24 or 30 inch screen TV that does frame interpolation?

[jagabo]

I don't know if there any TVs that small with motion interpolation. The other possible solution is to just sit farther away from a big screen.