deinterlacing question at DVinfo.net

Alain Aguilar · May 8th, 2004, 07:14 PM

I just created a file in Premiere using the Microsoft DV compression. I imported this file into After Effects. Now can I run deinterlacing after the file has been compressed?, let's say from AF, or should I've done this with the original footage from Premiere?.
I'll appreciate any suggestions

Casey Visco · May 9th, 2004, 11:58 AM

Doesnt matter at this point, it was interlaced in the camera to begin with, so de-interlacing it in Premiere will not gain you anything. I don't think either program has a decent de-interlacer, but i'd bet After Effects might do a *slightly* better job.

Alain Aguilar · May 9th, 2004, 12:05 PM

One of the reasons I broght this up is because during one of my renderings I was able to see a slight horisontal line right in the middle of the footage. It was really thin, I have made more versions of the same footage file using Magic Bullet and I think the thin line went away. But I was just wondering if deinterlacing is something that I should do all the time.

John Britt · May 9th, 2004, 05:23 PM

Actually, After Effects will allow you to deinterlace in a way slightly more sophisticated than just a "one-click" deinterlace function.

What I do in After Effects (a method you can find many mentions of here at dvinfo and elsewhere) is this:

*Import *two* copies of the video file.

*Right-click on the first copy and select Interpret Footage --> Main

*Under "Fields and Pulldown," at the "Separate Fields" drop-down, choose "Upper Field First." And check the "Motion Detect" box. Click OK

*Do the same for the second copy of the file, except at the "Separate Fields" drop-down, choose "Lower Field First."

*Drop the first copy into your composition. Then drop the second one in below it.

*Lower the top copy's opacity to 50%

In my opinion, this gives a better deinterlacing than something like Premiere's "one-click" solution.

That said, if you already own Magic Bullet, why not just stick with that -- aren't MB's deinterlacing capabilties really good to begin with?

As for when should you deinterlace -- I'd say if you need a non-interlaced final product, then you should deinterlace before you start adding graphics and other footage that comes from non-interlaced sources. For example, if you want to use After Effects to composite your original DV footage with images made in Photoshop, or if you want to add titles (especially ones that move), then I would deinterlace before adding those elements.

Alain Aguilar · May 9th, 2004, 09:28 PM

Thanks for that info. I actually followed that DVinfo technique, I also tried Magic Bullet. Does MB performs the deinterlacing automatically after you apply the film look presets?. I think the horizonatl line appeared because I did something wrong at first. Well is no longer there and I'm happy with what magic bullet does. I'll post my short pretty soon, I hope you guys check it out.

Al

May 8th, 2004, 07:14 PM	#1
Alain Aguilar Regular Crew Join Date: Sep 2003 Location: North Bergen Posts: 170	deinterlacing question I just created a file in Premiere using the Microsoft DV compression. I imported this file into After Effects. Now can I run deinterlacing after the file has been compressed?, let's say from AF, or should I've done this with the original footage from Premiere?. I'll appreciate any suggestions __________________ Alain

May 9th, 2004, 11:58 AM	#2
Casey Visco Major Player Join Date: Nov 2001 Location: Boston, MA Posts: 280	Doesnt matter at this point, it was interlaced in the camera to begin with, so de-interlacing it in Premiere will not gain you anything. I don't think either program has a decent de-interlacer, but i'd bet After Effects might do a slightly better job. __________________ Casey Visco Glidecam Industries, Inc.

May 9th, 2004, 12:05 PM	#3
Alain Aguilar Regular Crew Join Date: Sep 2003 Location: North Bergen Posts: 170	One of the reasons I broght this up is because during one of my renderings I was able to see a slight horisontal line right in the middle of the footage. It was really thin, I have made more versions of the same footage file using Magic Bullet and I think the thin line went away. But I was just wondering if deinterlacing is something that I should do all the time. __________________ Alain

May 9th, 2004, 09:28 PM	#5
Alain Aguilar Regular Crew Join Date: Sep 2003 Location: North Bergen Posts: 170	Thanks for that info. I actually followed that DVinfo technique, I also tried Magic Bullet. Does MB performs the deinterlacing automatically after you apply the film look presets?. I think the horizonatl line appeared because I did something wrong at first. Well is no longer there and I'm happy with what magic bullet does. I'll post my short pretty soon, I hope you guys check it out. Al __________________ Alain

May 9th, 2004, 05:23 PM	#4
John Britt Major Player Join Date: Sep 2003 Location: Atlanta, GA Posts: 621	Actually, After Effects will allow you to deinterlace in a way slightly more sophisticated than just a "one-click" deinterlace function. What I do in After Effects (a method you can find many mentions of here at dvinfo and elsewhere) is this: Import two* copies of the video file. Right-click on the first copy and select Interpret Footage --> Main Under "Fields and Pulldown," at the "Separate Fields" drop-down, choose "Upper Field First." And check the "Motion Detect" box. Click OK Do the same for the second copy of the file, except at the "Separate Fields" drop-down, choose "Lower Field First." Drop the first copy into your composition. Then drop the second one in below it. *Lower the top copy's opacity to 50% In my opinion, this gives a better deinterlacing than something like Premiere's "one-click" solution. That said, if you already own Magic Bullet, why not just stick with that -- aren't MB's deinterlacing capabilties really good to begin with? As for when should you deinterlace -- I'd say if you need a non-interlaced final product, then you should deinterlace before you start adding graphics and other footage that comes from non-interlaced sources. For example, if you want to use After Effects to composite your original DV footage with images made in Photoshop, or if you want to add titles (especially ones that move), then I would deinterlace before adding those elements.