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unwanted compression artifacts

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Keith Betts
unwanted compression artifacts
on May 19, 2014 at 1:14:13 pm

I shoot dance recitals where the school has placed lines of tape on the stage floor for dancer placement. Great for them and bad for me! Although it doesn't appear in raw footage or exported ProRes Master file but in my compressed file the lines fluctuate and wave and are a utter distraction to me. Tried different compression settings to but to no avail. Anyone ever come across a similar situation? Don't think school will remove the lines on the floor so I have to change my compression settings to compensate or learn to accept the wavy lines. Any suggestions greatly appreciated.


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Ivan Myles
Re: unwanted compression artifacts
on May 20, 2014 at 1:55:06 pm

[Keith Betts] "Although it doesn't appear in raw footage or exported ProRes Master file but in my compressed file the lines fluctuate and wave and are a utter distraction to me. Tried different compression settings to but to no avail."

Please provide more detailed information: codec, screen capture of best export settings, screen capture or clip of the issue, how the video is being viewed.


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Keith Betts
Re: unwanted compression artifacts
on May 20, 2014 at 11:22:04 pm

What I'm currently doing is comparing the DVD compression preset for Compressor 4.1.1 versus the DVD preset for Sorenson Squeeze 9.0.3.11 for the same video file I referenced in my initial post. It appears that while Squeeze took an extremely long amount of time to do a 2 pass compression it has eliminated the unwanted artifacts resulting from the taped markings on the stage floor. Any experience or recommendations for encoding/compression software? While the price differential is huge between the two apps if the Squeeze preset eliminates those artifacts I certainly won't have any buyer's remorse. Now I have yet to build/master a DVD from this compressed file with my authoring app of choice, Adobe Encore; but I'm certainly hopeful the extra cost for Sorenson Squeeze was worth it!


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Keith Betts
Re: unwanted compression artifacts
on May 21, 2014 at 6:43:48 pm

Here's a link to a 1 minute clip that displays this unwanted effect:
http://reels.creativecow.net/film/taped-lines-causing-problems-with-mastere...

Think I've narrowed the problem down to Adobe Encore as the culprit. Could be my selection of Field Order. But I have tried several different variations of Field Order and get the same unwanted effect. Driving me crazy. Never encountered anything like this in all of my years compressing video.

Original file was ProRes Master with current settings from FCPX. Purchased Sorenson Squeeze hoping it would do a better job of compression compared to Compressor. It appears this may be true but my final product is a standard def DVD that encounters this wavy lines issue.

Any recommendations?


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Chris Borjis
Re: unwanted compression artifacts
on May 30, 2014 at 4:37:41 pm

Adobe media encoder is quite capable of good encoding, but
I never use the default settings. I make custom tweaked
ones for DVD and Blu-Ray encoding...never had a client complain about
image quality.



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Keith Betts
Re: unwanted compression artifacts
on May 30, 2014 at 6:04:58 pm

What's your app of choice for authoring or burning DVD's? Don't think my problem lies with the compression phase of my workflow but in the authoring stage. The taped lines on the stage floor that are causing me problems won't be removed. They're necessary for dancer alignment. I'm trying to figure out why these lines fluctuate and wave during playback of my std def DVD. Any ideas? Once again they don't appear with my raw footage or my compressed file.


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Chris Borjis
Re: unwanted compression artifacts
on Jun 3, 2014 at 5:10:35 pm

It's likely not the authoring, unless you have it set to re-compress the content
or if it's out of spec and forcing a re-compress.

But I use DVD Studio Pro for Authoring.

if you view the mpeg2 files in mpeg stream clip you might be seeing those lines.

Sometimes those sorts of issues are just not going to look great on DVD format.
For example, if you had DV footage with any pure red in it, because of the
lack of color sampling you will see cross hatched alias artifacts when
compressing to mpeg2 for DVD. Nothing would be able to solve that.



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Keith Betts
Re: unwanted compression artifacts
on Jun 3, 2014 at 7:43:12 pm

I think some of the problem lies in simply viewing a standard definition DVD on a HD video monitor which is where many consumers/households are. Most have 1 or more HD TV's yet have not adopted BluRay to their home entertainment system. That's why I must deliver my final product as a std def DVD and not BluRay. If I recall correctly, the fluctuating and waving lines do not appear with my BluRay version of the same event.

How can I be assured my Adobe Encore authoring program is not re-compressing my video files?


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Chris Borjis
Re: unwanted compression artifacts
on Jun 4, 2014 at 4:21:24 pm

[Keith Betts] "How can I be assured my Adobe Encore authoring program is not re-compressing my video files?"

when you start the disc build process, it will immediately begin building
it instead of the long process of encoding. You can also set it somewhere
not to encode.

one other option to try that I have done with difficult material is
to export the video in a lossless format in SD, then run it through
media encoder for DVD.

Sometimes the resizing is better when not done in the DVD encoding stage.

I even went so far with one film to run it through my kona 3g to downconvert
it in hardware as it just would not look good being resized in compressor
or media encoder.



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Brian Cheng
Re: unwanted compression artifacts
on Jun 11, 2014 at 3:32:53 am

I think your video is interlaced


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Keith Betts
Re: unwanted compression artifacts
on Jun 11, 2014 at 3:50:25 am

It was shot progressive at 1280 x 720 60p. Exported as an Apple Pro Res 422 Master file from Apple FCPX. It was then compressed with Compressor 4.1 into an MPEG -2 video file and imported as a Timeline in Adobe Encore for standard DVD authoring. Is it possible that Encore interlaced my progressive file during the authoring & build process? Any ideas to prevent that in Encore? I'll be following the same workflow for a long form event in a few weeks.


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Brian Cheng
Re: unwanted compression artifacts
on Jun 11, 2014 at 3:56:05 am

I'm not an expert or anything, sorry. But your video does looked like it's interlaced or something similar.
Maybe your frame rate is too high, and when image quality isn't good, it looks bad because the frames are going so fast.

Movie Director
Stop Motion Animator (Canon 100D, 24FPS)
Palie Studios


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