Best Software Options for Deinterlacing

Hi,

Is Teranex the gold standard for deinterlacing?

Is there any software that can produce comparable results?

Since all my video content is in file form, is it possible to output from one computer (interlaced) to a Teranex and capture (deinterlaced) into another computer?

Thank you.

Teranex maybe was gold standard for deinterlacing, not so sure now. I assume it's still good, but buying box (and doing whole realtime chained work) just to do bit of deinterlacing is bit overkill for me, specially when you have files.
From more expensive ones- Tachyon is good as well as Alchemist. Episode is decent. Adobe is soft. I think Compressor is also ok.
You can use ffmpeg which has many options for deinterlacing, which are also ok, but best results can be achieved with avisynth\vapoursynth. It can easily match Tachyon or Alchemist.

Do you need to go to single fps, so eg 50i to 25p or double 50i to 50p?

I have script which does very nice 50i to 25p (or other fps). What is good about it is fact that in case of mixed footage it won't touch progressive parts (well with 99% accuracy). You can pm me, but I don't share it for free (it's cheap though).

as well as Alchemist

Alchemist is excellent for progressive to progressive or interlaced to interlaced framerate conversions, and also interlaced to progressive conversions where it can lock to cadences and remove them, but the deinterlacing performance for pure video material is unfortunately far behind the Teranex or software solutions. Teranex keeps most of the vertical resolution when doing same framerate conversions (29.97i to 29.97p for example) without aliased edges or flickering lines most of the time, Alchemist often has flickering lines and reduced vertical resolution on this kind of conversions.

Thank you Andrew, and Marcus for your time and thoughts.

Does Avisynth maintain vertical resolution? Avi/Vapoursynth sounds like a possible solution but there's just one problem. I'm not a programmer. The sites are very intimidating. Is there a step by step guide to using the program to perform the deinterlace? Also am I right that there are a range of scripts for deinterlacing? Why is this? Has anyone tried running either software on a Mac, is doing this buggy? Should I be focussing on Avi or Vapour if all I want to do if learn to deinterlace? Is there a sort of 'idiots guide' to doing this?

as well as Alchemist

Alchemist is excellent for progressive to progressive or interlaced to interlaced framerate conversions, and also interlaced to progressive conversions where it can lock to cadences and remove them, but the deinterlacing performance for pure video material is unfortunately far behind the Teranex or software solutions. Teranex keeps most of the vertical resolution when doing same framerate conversions (29.97i to 29.97p for example) without aliased edges or flickering lines most of the time, Alchemist often has flickering lines and reduced vertical resolution on this kind of conversions.

Are you talking about Alchemist hardware box or software (xFile)?
xFile does decent deinterlacing, although sometimes it leaves bit of combing. Hardware box has "compromises" as it has to process in realtime.
Interlaced to interlaced conversion also always uses deinterlacing, as actual frame interpolation is always done on progressive frames.

Thank you Andrew, and Marcus for your time and thoughts.

Does Avisynth maintain vertical resolution? Avi/Vapoursynth sounds like a possible solution but there's just one problem. I'm not a programmer. The sites are very intimidating. Is there a step by step guide to using the program to perform the deinterlace? Also am I right that there are a range of scripts for deinterlacing? Why is this? Has anyone tried running either software on a Mac, is doing this buggy? Should I be focussing on Avi or Vapour if all I want to do if learn to deinterlace? Is there a sort of 'idiots guide' to doing this?

Vapoursynth is fine on Mac.
There is no real guide- it's all your experience+ others scripts and forum help.
There are many different filters for deinteralcing- from simple/fast to very complex and slow. Best ones can easily compete with best pro/hardware deinterlacing out there.

I'm actually working now on project with almost 2000 files (80 000 minutes) which need to be deinterlaced (they vary: from 100% progressive through hybrid to 100% interlaced). My script passes progressive frames untouched, which also speeds up whole process.

Alchemist hardware, but I've also seen samples from the software version, the deinterlacing of video based material was always inferior to Teranex deinterlacing (applies only to same framerate deinterlacing).

The best workflow for me in terms of quality is to do the deinterlacing with Teranex and the framerate conversion of the progressive output with Alchemist.

I have not done any direct test with Teranex.
Well- going to single fps is easier, going to double fps (eg 50i to 50p) is way more demanding and this is what is needed for any fps conversion.
I'm using middle quality script (non-motion adaptive one due to processing time), but even this provides good quality.

Thanks for the responses, and thanks for the examples Andrew, they do look good. I'll mostly be going from traditional standard definition interlaced (25i?) to 25p. The script you're using that simply ignores anything that's already progressive does sound good. What does that script do with progressive segmented frames? Thanks for the script offer, might take you up on it. I'll take a look at Vapour and see if I can get my head around it first.

PsF is purely SDI thing. It's just progressive data in file based world when properly captured.
The only possible issue is chroma positioning, but this should be handled by capture card.

If you process by "series" (similar nature content) you can get very decent result with vs.
I'm trying to get average script for 2000 files of very different nature, but this proves to be bit tricky.

I've just noticed you said "mainly SD". In this case put everything through QTGMC which will give you crazy good results and for SD speed will be acceptable (assuming 6cores+ machine).

[Rohit Gupta]

Hi,

Is Teranex the gold standard for deinterlacing?

Is there any software that can produce comparable results?

Since all my video content is in file form, is it possible to output from one computer (interlaced) to a Teranex and capture (deinterlaced) into another computer?

Thank you.

Have you tried the de-interlacer in Resolve? In Clip Attributes, there is a "Enable Deinterlacing" checkbox.

Deinterlacing itself is ok in Resolve (with High Quality selected) with slight combing artefacts left (and issues on diagonals for static parts of the frame), but problem is that if you have some hybrid clips progressive parts will be badly affected.
When you try to normalise files this is not good. What you want is a solution where you can put all files through without worry about hybrid nature.
Resolve also only offers deinterlacing to single fps ( I assume is not a problem in this case). Speed is good though.

Here is main problem with Resolve deinterlacing.

Original 50i recording:


Resolve:


QTGMC:


Resolve destroys diagonals on static parts of the frame- not sure why (looks like a bug related to whole field processing engine) if it's motion adaptive deinterlacer which quite well recovers missing fields details.
QTGMC is a beauty and has endless possibilities (and relatively slow speed ).

Andrew,

What are your thoughts about RevisionFx FieldsKit?

In your example, in which you compare Resolve's Deinterlace, where in the frame should I be looking to see the most pronounced difference? Do you have an example that perhaps has more motion in which the interlaced artefacts are more highly pronounced?

Resolve result is unusable- look at bench edge (make sure you clicked on images and looking at 1:1 pixels preview). Best to load them to Photoshop/NLE and swap between at 1:1 preview.

RevisionFx FieldsKit should be good, but this is crazy slow if I remember well. It will be also most likely used in app which works in RGB which is somehow undesired in this case and can be source of possible color issues.

I see it now. It's a remarkable difference.

Yep, you can blindly put your files through QTGMC filter with medium preset and you will be more than happy

[Rohit Gupta]

Deinterlacing itself is ok in Resolve (with High Quality selected) with slight combing artefacts left (and issues on diagonals for static parts of the frame), but problem is that if you have some hybrid clips progressive parts will be badly affected.
When you try to normalise files this is not good. What you want is a solution where you can put all files through without worry about hybrid nature.
Resolve also only offers deinterlacing to single fps ( I assume is not a problem in this case). Speed is good though.

Is your project setup to do field processing? Can you keep that off to test this? Are you able to PM me a link to the original clip, and the de-interlace result you like, and we will check it out.

It's off (you actually can't deinterlace when it's on).

I will upload files.

Hi Rohit,

Can you please also address the problem of jagged diagonals when deinterlacing using Resolve? Is there a solution within Resolve, and is this problem also experienced when deinterlacing using the Teranex?

Deinterlacing itself is ok in Resolve (with High Quality selected) with slight combing artefacts left (and issues on diagonals for static parts of the frame), but problem is that if you have some hybrid clips progressive parts will be badly affected.
When you try to normalise files this is not good. What you want is a solution where you can put all files through without worry about hybrid nature.
Resolve also only offers deinterlacing to single fps ( I assume is not a problem in this case). Speed is good though.

I'm wondering what you mean by " Hybrid Clips"? AFAIK clip format will be either progressive OR interlaced but not a combination of both.

Have you not seen clips which have double nature scenes?
There are plenty of them, everywhere. Some scenes are shot progressive, some interlaced, so you end up with hybrid file nature. Actual flag is useless in such a case. In most cases files are flagged interlaced, but it means not much.
I have 80K minutes of broadcast masters and all fo them are flagged as interlaced, but in reality 50% are pure 100% progressive content, which don't need any processing. There are some where 95% is progressive, but 5% scenes are interlaced (or opposite). There are also cases where for example whole actual content is progressive, but rolling credits are interlaced for better roll. All of this creates massive issues when you're trying to prepare such a files for web etc. where they have to be progressive. In this case you need good tool which either has ability to detect progressive parts and simply pass them through or one which only slightly affects progressive parts. Both of those things are supported in eg. vapoursynth where actual deinterlacing (filling missing field details) itself is also very good.

Resolve destroys diagonals on static parts of the frame- not sure why (looks like a bug related to whole field processing engine) if it's motion adaptive deinterlacer which quite well recovers missing fields details.
QTGMC is a beauty and has endless possibilities (and relatively slow speed ).

Have you tried the High Quality deinterlacing switch? It's in the Image Scaling tab of Project Settings.

The high quality mode doesn't always work better, but most of the time. It's worth a try.

When I compared our Teranex to Davinci's deinterlace at High Quality, I didn't find much difference. Maybe they use the same algorithm?

The thing with interlaced footage is that some footage deinterlace much better than some other. I think it might have to do with the camera's amount of sharpen and amount of deatil in the scene. Lots of older Betacam had lots and lots of sharpening going on.

Yes, it was High Quality mode.
QTGMC has no problems with any source and its 100 parameters allow you to tweak anything (or you just use one of few presets).

Yes, it was High Quality mode.
QTGMC has no problems with any source and its 100 parameters allow you to tweak anything (or you just use one of few presets).

That's interesting. I might give QTGMC a new test. Can you share your usual settings or is the default pretty good?

Thanks

Just stick with presets and you will be happy. For SD you can use Medium or Slow, for HD use Fast.
Go to doom9 forum if you need more help or avisynth/vapoursynth scripts.