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Horizontally scrolling text fine on TV, horrible on Quicktime

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Aj Koch
Horizontally scrolling text fine on TV, horrible on Quicktime
on Dec 16, 2009 at 1:15:58 am

I have a client that brought a project with rapidly horizontally scrolling text to me, asking to fix the "jitter" she was having with playback on her television. I easily fixed it by rendering the text lower field dominant, but now she wants an approval quicktime, and on the quicktime, which apparently compresses progressively, is showing the text in it's ugly, ugly fields.

For a quick fix, I tried deinterlacing the text and exporting a quicktime, but it only minimally improved the look of the text.

Is there a way to get the text to look smooth in quicktime format? Specifically, photo-JPEG or H.264? Or do I need to explain that quicktimes just don't disply horizontally scrolling text very well?

Thanks in advance.

-Aj


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Daniel Low
Re: Horizontally scrolling text fine on TV, horrible on Quicktime
on Dec 16, 2009 at 6:47:17 am

[Aj Koch] "Or do I need to explain that quicktimes just don't disply horizontally scrolling text very well? "

No, you should tell the client that you don't know enough about Quicktime to help.

[Aj Koch] "I have a client that brought a project "

What kind of project?

[Aj Koch] "with rapidly horizontally scrolling text to me, asking to fix the "jitter" she was having with playback on her television"

What kind of television? (CRT or Flat Panel)

[Aj Koch] "and on the quicktime, which apparently compresses progressively"

Quicktime is a wrapper than can contain codecs that are both progressive and interlaced so whoever told you that was wrong.

[Aj Koch] "For a quick fix, I tried deinterlacing the text and exporting a quicktime, but it only minimally improved the look of the text.

Perhaps you didn't deinterlace it very well.

[Aj Koch] "Is there a way to get the text to look smooth in quicktime format?"

In the same way as you would with any other video format.



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Aj Koch
Re: Horizontally scrolling text fine on TV, horrible on Quicktime
on Dec 16, 2009 at 5:18:00 pm

[Daniel Low] "What kind of project?"

The horizontally scrolling text was built in After Effects, rendered as an animation Quicktime, then imported into Final Cut Pro for playback and layoff purposes.

[Daniel Low] "What kind of television? (CRT or Flat Panel)"

Both. Since the client had originally rendered the text with no field dominance in After Effects, and Final Cut plays back lower field first, both my Flat Panel AND CRT were showing field jitter.

[Daniel Low] "Quicktime is a wrapper than can contain codecs that are both progressive and interlaced so whoever told you that was wrong."

As I mentioned, the client would like the Quicktimes in photo-JPEG or H.264, which are codecs, according to the settings available to me, that do not allow for interlaced compression. Compressing the video in a codec that allows interlacing, like DV/DVCPRO, would result in too large a file size, so that is not an option. The purpose of this Quicktime is for approval.

[Daniel Low] "You should tell the client that you don't know enough about Quicktime to help."

Alternatively, I could ask about the subject on Creative Cow, and possibly learn something. That's why people ask. To learn.

[Daniel Low] "Perhaps you didn't deinterlace it very well."

Perhaps you could have offered suggestions to my problems instead of trolling. Perhaps that would have been a better use of your time, and mine.

[Daniel Low] "In the same way as you would with any other video format."

...Is there anyone out there with actual knowledge on the subject, that might be able to offer any real suggestions or help?


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Chris Blair
Re: Horizontally scrolling text fine on TV, horrible on Quicktime
on Dec 17, 2009 at 1:37:40 am

What pixel size/resolution is the "fixed" file? If I understand correctly, it sounds like someone created an animation and rendered it progressively without motion blur, which would create the horizontal jitter you describe on text that's quickly moving horizontally.

So a couple questions:

1. What exactly did you do to fix it? It doesn't seem that converting/transcoding the file with interlacing would improve it much since each field would just be half of the original progressive frame without the usual difference between the two fields that helps smooth motion (If that makes sense).

2. How are you exporting it...meaning to what pixel size and frame rate?

I've seen the issue you describe only when an animation is created progressively without motion blur, and in this case the jitter you describe is inherent in the original file. The BEST solution would be to rerender the original project progressive with motion blur, or interlaced without motion blur if render time is an issue.

If that's not an option, the next best would be to take your "fixed" version and reduce the pixel size/resolution upon export. So if the original is 1280x720, output your preview at something like 640x360, 512x288 or 480x270 and don't deinterlace the output. You might get a little bit of interlace artifacts but the motion shouldn't be jittery.

Give us some more info and we could probably help more.

Chris Blair
Magnetic Image, Inc.
Evansville, IN
http://www.videomi.com


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Chris Blair
Re: Horizontally scrolling text (progessive to interlaced tutorial)
on Dec 17, 2009 at 1:41:47 am

Here's a Cow tutorial on changing a progessive source to interlaced in After Effects...but...I'm still suspect that this would fix a fast horizontal move that doesn't have motion blur applied (the way a camera would add it if you were panning).

http://magazine.creativecow.net/article/interlacing-progressive-footage

Chris Blair
Magnetic Image, Inc.
Evansville, IN
http://www.videomi.com


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Haley Stibbard
Re: Horizontally scrolling text (progessive to interlaced tutorial)
on Sep 1, 2010 at 8:57:19 am

Hi

I am having this issue too, horizontal text crawling accross screen, rendered out upper fields in after effect, placed in upper field project sequence in final cut, looks great on broadcast monitor and plasma attached preview monitor and final cut window, as soon as I expor to h264 for tv station, text crawl has obvious feild issues. Im tearing my hair out and h264 export from final cut wont let you choose upper or lower fields when you export. I thought it was looking bad in the quicktime as it was being veiew on the monitor, but stations are still saying it will go to air this way, can anyone help?

cheers


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