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Losing quality in Compressor

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Paul Raila
Losing quality in Compressor
on Apr 5, 2010 at 6:01:51 am

Hello,

I'm working on a Mac, version 10.6.3, editing in FCP version 7.0.2, using Compressor version 3.5.2.

I've been having this problem for a while now. I'm shooting with a Canon 5D MK II, converting footage to ProRes 422 HQ before I edit. No problems yet.

I export from FCP as a Quicktime movie (no compression), making the movie self-contained. Image still looks great at this point.

I import to Compressor and compress using the DVD Best Quality Settings - MPEG 2. The final output will be standard def. DVD.

Here is where the problem occurs, I think. I compress, and my footage looses quality. Smooth lines become jagged, smooth text becomes jagged too. How do I maintain the clarity I began with while exporting to a SD DVD file?

I have a project that's 75 minutes long, so the highest I can get the average bit rate is 6.7 or so.

What am I doing wrong? My footage looks beautiful before I compress. Can I do H.264 maybe, and import that into DVD Pro?

Thanks in advance....


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Brian Alexander
Re: Losing quality in Compressor
on Apr 5, 2010 at 8:36:09 pm

[Paul Raila] "I export from FCP as a Quicktime movie (no compression), making the movie self-contained. Image still looks great at this point. "

You could export a reference file, it would save you time by not creating a stand alone file.

[Paul Raila] "Here is where the problem occurs, I think. I compress, and my footage looses quality"

Your creating a downconverted standard def file. It is going to take a hit in quality, this is normal.

[Paul Raila] "How do I maintain the clarity I began with while exporting to a SD DVD file?"

What are you viewing this encoded DVD with? Are you looking at it on your computer and letting your computer scale it to full screen or are you looking at this on a DVD player connected to a CRT?

The way to view this file on your computer would be to view it at a 100% zoom or actual size with the deinterlacing filter turned off. This will look pretty small on your monitor if you're running at a high resolution but it will give you an accurate representation of what the quality really is.

[Paul Raila] "Can I do H.264 maybe, and import that into DVD Pro? "

I wouldn't do this. You would be essentially compressing (transcoding) the video twice, you won't get a good result like this. This would be the same as recording a video from HDCam SR to HDV to DVD. This analogy is not perfect but you get the point, generation loss each step.

I don't know the Mk II very well, what does it record natively, interlaced/progressive, 720 or 1080?


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Paul Raila
Re: Losing quality in Compressor
on Apr 5, 2010 at 11:22:14 pm

Hi Brian, thank you for responding.

The 5D shoots 1080p, Quicktime H.264 files, linear PCM.... I read somewhere else something about MPEG-4 files as well. Not sure about that.

Before I edit, I turn every file into ProRes 422 HQ.

I have a 75 minute project that I'm compressing into an MPEG-2, and everything becomes jagged. No smooth lines on text, or faces etc... It's not just that way through my DVD player. I view the MPEG-2 on my computer monitor and see the same jagged lines. They're really pronounced on text, when as a .mov file, the text, and subject matter, is silky smooth.

Thanks for your help!

p.s. The problem isn't the horizontal interlace lines. It's almost like I'm seeing pixels on peoples faces, text borders, any movement...


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