Jagged Edges/Aliasing Render Issues Downconverting from HD to SD in FCPX

Question

Level 1

0 points

Jagged Edges/Aliasing Render Issues Downconverting from HD to SD in FCPX

Hi Guys - I've finally made the jump from FCP7 to FCPX and have had a pleasant experience so far until now. I do a lot of HD to SD down-conversions after my editing is complete. As you can see from the screenshots below, I'm seeing aliasing issues on my rendered footage.

FCP7 (perfect) : http://i.imgur.com/mJo9F7d.jpg

FCPX (aliasing) : http://i.imgur.com/kbO8Pqa.jpg

On FCP7 I would simply go to the Sequence settings and change the Field Dominance setting to NONE and continue with exporting the HD timeline to Compressor and using the 90 min DVD setting and my rendered footage would look great!

I cannot seem to find a way to do this in FCPX. I know you can set the clips' Field Dominance "Override" setting to None Set, Upper Field, Lower Field and Progressive. I've tried all 4 options and none seem to fix the issue. Even when I open Compressor and view the exported timeline from FCPX, it states that it is Upper Level eventhough I've changed the clips to the other 3 settings.

Any ideas how to fix this? Am I missing something? Is there something similiar to FCP7's way?

Thanks.

Final Cut Pro X

Posted on Mar 4, 2013 11:37 PM

Reply

Answer 1

Mar 5, 2013 12:01 AM in response to mosdefff

Hi

No not using FinalCut Pro X - only FinalCut Pro 6 and iMovie HD6

BUT I've seen what Your photos looks like and I interpret this as - an Interlace issue.

If You aim to do a Standard Video-DVD - then You need

• interlaced SD-Video

else You lose in quality - from poor to even Bad. Feeding iDVD or DVD Studio Pro or other DVD authoring program HD and progressive material - USUALLY doesn't improve but decrease the quality on the final DVD.

Interlaced Video can start drawing line 1 then 3 then 5 = Starts with odd numbers - Next frame is Even numbered lines.

If This is set to go Even first - the result is disastrous and looks pretty much like Your Photos

I got this when reversing a Clip to go Backwards - and by changing the setting of it - All was well.

Hopefully that is the same for You.

Yours Bengt W

Reply

Answer 2

Mar 5, 2013 12:10 AM in response to mosdefff

As Bengt has told you, it is not aliasing but simply normal interlacing which has nothing to do with downconverting.

It's there in the original hi-def and is perfectly normal.

If you burn your video to DVD and play it on a TV you will not see it.

It only appears when viewed on a computer screen, so I assume you are watching it on your Mac.

How are you sharing (exporting) your finished projects?

Reply

Answer 3

mosdefff Author

Level 1

0 points

Mar 5, 2013 12:22 AM in response to Ian R. Brown

Thanks for the feedback however I can use the same footage in an HD timeline in FCP7 and the rendered footage looks fine (as shown in the picture which is how I got the screenshot).

I did burn the rendered file to DVD and watched it on my TV and it looks exactly the same as on my monitor.

Another problem is that my titles are all jagged/aliasing as well, whereas if I render the same timeline out including the titles in FCP7, all looks fine on monitor and DVD-TV.

In FCP7, all I had to do was set the Dominance Field to NONE and this issue was eleviated.

Reply

Answer 4

mosdefff Author

Level 1

0 points

Mar 5, 2013 12:27 AM in response to mosdefff

There is no way to force the timeline in FCPX to NONE for Field Dominance? As said in my first post, no matter which field I use for my clips in the timeline, Compressor keeps saying its upper field.

Reply

Answer 5

Mar 5, 2013 12:43 AM in response to mosdefff

The reason you didn't see the interlacing lines in FCP 7 is because it was set to hide them.

You can do the same in FCP X by clicking the little icon (arrowed) and deselecting "Show Both Fields".

There is no way you should be seeing the interlacing lines on a TV unless you are freezing the picture.

Viewed normally they should be invisible as they are in every TV programme.

Exactly how are you exporting?

Reply

Answer 6

mosdefff Author

Level 1

0 points

Mar 5, 2013 12:54 AM in response to Ian R. Brown

In FCP 7:

- Drag my HD clips in an HD timeline and then go to Sequence Settings and change Field Dominance to NONE.

- File>Share>Choose my custom bitrate settings from Compressor

I had picked up this tip from Creative Cow's site after noticing the aliasing 2 years ago when I started receiving HD footage and clients wanted their videos on DVD. This trick fixed the aliasing and decreased my render/transcoding times by half.

I can post a picture of the aliasing on my TV if you like and I'm not pausing the video.

Also I don't see any aliasing in FCPX, only on the rendered file. And I have "Show both fields" off.

Reply

Answer 7

Mar 5, 2013 1:40 AM in response to mosdefff

Exactly how are you exporting in FCP X ?

Reply

Answer 8

mosdefff Author

Level 1

0 points

Mar 5, 2013 1:52 AM in response to Ian R. Brown

Same way:

File>Share>Choose my custom bitrate settings from Compressor

I have even done: File>Send to Compressor, chose my bitrate settings and Compressor still outputs the rendered aliasing file.

Reply

Answer 9

Mar 5, 2013 1:59 AM in response to mosdefff

What are the Compressor settings/presets you are using?

What is the original video format . . . and don't say "HD"? 😉

Incidentally the problem shown in your screenshot is not aliasing and has nothing to do with aliasing.

Aliasing produces a zig zag line.

These are classic interlacing lines.

Reply

Answer 10

mosdefff Author

Level 1

0 points

Mar 5, 2013 2:38 AM in response to Ian R. Brown

Compressor settings: SD-DVD MPEG-2 NTSC 29.97 16:9 Bottom First 8Mbps one-pass CBR

Original Video: 1080i HD 1920x1080 29.97i Apple ProRes 422

My titles are definitely aliasing as is my video. I can see it on the edges of people's faces. Perhaps the screenshot I sent did not portray it accurately enough. I can upload a video if you like to show you. Their faces, edges of clothes, chairs are all jagged (zig-zagged).

Update:

Perhaps it looks like it is aliasing because the video is moving. I posted another screenshot below. If you say its interlacing, I believe you. You are the expert.

http://i.imgur.com/HgYNfQf.jpg

Reply