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unacceptable jagged edges

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jjjohnson
unacceptable jagged edges
on Nov 1, 2007 at 12:37:14 pm

Using Final Cut Studio with Sapphire plug-ins I created an undulating wave pattern with light rays keyed over super saturated ever changing color background. I used the TGA codec for some elements for which I needed to preserve an alpha channel. Then I layered several of these waves over a black background. Rendered them and output a QT using the DV/NTSC codec. Brought that into another sequence to apply a final mask and then output using Compressor in order to make a looping SD DVD.

Compressor added an unacceptable amount of jagged edges. I have tried different codecs at the QT stage but with the same result. I have used 2 pass VBR with a variety of bit rates with no different results.

Should I try BitVice? Add a glow around the entire piece? (although blurring the image didn't make a difference either)

I am at a loss.



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epontius
Re: unacceptable jagged edges
on Nov 1, 2007 at 2:16:25 pm

I'm no FCP expert, but perhaps you should try exporting to a lossless codec (animation, etc...) rather than the rather brutal DV codec and then import it into another sequence to apply your final mask and then export to your SD DVD.
Also check your field order at each stage and view the SD on an interlaced display (TV), jagged edges are often caused by field order mismatch or de-interlacing deficiencies in computer software DVD players.

Erik


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jjjohnson
Re: unacceptable jagged edges
on Nov 1, 2007 at 2:27:02 pm

I did try the animation codec when making the QTs but the error remained. It appears to occur in the compression step. The final is to be projected. I was using progressive 16 x 9 instead of interlaced at every stage of the process.



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Danny2007
Re: unacceptable jagged edges
on Nov 2, 2007 at 4:24:28 pm

Most probable reasons for jaggies are:

Lousy codec/heavy compression.
Bad deinterlacing
Bad or incorrect scaling.
Mixing up square and non-sqaure pixel formats (as you may have done)

What was the sequence in FCP set to? DV?


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jjjohnson
Re: unacceptable jagged edges
on Nov 2, 2007 at 5:14:44 pm

Final cut project was set to DV. The effect renders well and plays back as a quicktime fine to an NTSC monitor hooked up to a DVCam deck. It just gets really ugly when I use compressor. I have most recently have goosed the data rate up to 7.9 mbs average at 9.0 max. I am waiting for that compression to conclude that I can burn a disk to see if it works.



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Aharon Rabinowitz
Re: unacceptable jagged edges
on Nov 4, 2007 at 5:06:43 am

is your compressor changing the pixel aspect ratio? If so, that can really mess things up. If you are working at a non-square PAR, check your compression settings - often they default to square pixel resolutions such as 640x480 instead of 720x486.

Aharon Rabinowitz
Email: arabinowitz (AT) yahoo (DOT) com
All Bets Are Off Productions, Inc.
Creative Cow After Effect Podcast
Internet Killed the Video Star: A Guide to Creating Video for the Web


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jjjohnson
Re: unacceptable jagged edges
on Nov 12, 2007 at 8:51:12 pm

After retracing my steps and modifying some of the sequences used to make this effect I think the error may be that some of my elements had "none" selected for field dominance while later sequences had lower field.



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