Deinterlacing Made Simple: What's the Best Way to Deinterlace Content?

[PlayStation 2]

While deinterlacing isn't a complex issue in of itself, you may be asking yourself "what's the best way to deinterlace this video I have?"

And I'm here to answer that question, at least locally.

 

To put it bluntly, there is no real end-all be-all solution varying on what you're trying to deinterlace, so let's go over some options here.

For demonstration purposes, I will be using this video to demonstrate various deinterlacing methods and how they function.

 

No Deinterlacing and How it Looks:

 

No deinterlacing just shows the two fields with no processing to disguise how the fields are shown as a final frame.

 

Here's how it generally appears, no matter the frame rate.



This isn't what you want for interlaced content.

 

 

Blend Deinterlacing and How it Looks:

 

Blending can work fine for certain things, but this isn't what you want for content that may properly deinterlace to 60fps.

 

We'll come back to this later.

Mean deinterlacing is just a slightly cleaner version of blending, really.

 

 

Bob Deinterlacing and How it Looks:

 

What bob deinterlacing is displaying each field as a separate frame, and then, if applicable, allow the display to deinterlace that. While this was very useful especially in early PlayStation 2 games, it comes off as looking very unusual for content that wasn't made with that in mind. Here it displays at 720x240 for each frame instead of 720x480.

 

 

 

Yadif Deinterlacing and How it Looks:

 

Yadif blends the two fields in a way where motion artifacts are much less noticeable than using something like blend deinterlacing.

Yadif 2x functions the same way but allows content to be properly deinterlaced at 60fps.

However, this comes at the cost of potentially visible artifacts like in these image.



Look at SpongeBob's eyelids in this picture for an example.



Note Mr. Krab's eyestalks and sleeves.

 

 

Yadif sounds like it'd work well. And for many cases, it does. However, if you don't want to deal with external filters and the content you're displaying doesn't benefit from a higher frame rate, it might be better to look into blending or mean deinterlacing.

 

Here's Yadif deinterlacing on The Wild Thornberrys Movie.

And here's blend deinterlacing on the same film, with the same clip.

Quite noticeably, no frame rate difference but the artifacts from Yadif that could arise are gone.

 

Here's a still from a higher contrast scene, using both methods.

Yadif:



Blend:


 

 

 

Final summary:

To shorten the whole thing into a couple of sentences, Yadif deinterlacing works well for content that was made for smoothness in mind. Home movies with a tape-based camcorder are a big one where Yadif would benefit greatly.

When it comes to films, however, Yadif is simply kinda pointless, and may introduce unwanted artifacts due to how the frame combining works, so in that context you'll likely be better off using a blending method.

 

I'm always willing to answer questions you have, at least regarding the thread.

Edited July 25, 2017 by Dan Castellaneta
Fixed some redundancy in the Yadif section.

[Gravnetic]

This is a really solid video with an After Effects file for de-interlacing and fixing old video blocking issues - http://www.videocopilot.net/tutorials/deinterlace_in_ae/