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MPEG-2 @ 50 MBps

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Matt Press
MPEG-2 @ 50 MBps
on Feb 10, 2009 at 4:10:14 pm

I have a client looking to encode a multiplexed MPEG-2 file @ 50MBps from DigiBeta. I have FCP and Cleaner XL at my disposal, and only Cleaner will allow me to go up to 50 MBps in MPEG-2 HD mode.

What would be the best workflow for this situation? This is the first time I have had a request for this. I understand ProCoder will do the job, but I'm not even sure why someone would be asking for this, especially since it is from an SD source.

Any help would be most appreciated.

-Matt


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Daniel Low
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 4:27:41 pm

They are more than likely asking for 50Mb/s I-Frame only MPEG-2 which is a typical broadcasters format. I'm pretty sure you can't do that in cleaner or compressor.

However Episode Pro from Telestream will do it.

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Matt Press
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 4:49:05 pm

That is exactly what they're looking for.

What kind of hard drive space would we need loading in 90 minute DigiBetas through Final Cut and then exporting to this format?

Thanks.

Matt



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Daniel Low
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 5:13:34 pm

I don't know.

How and at what rate are you capturing your digibeta?

Once you know that, either google or a calculator will tell you how much space you need.

This may also help:

http://www.digitalrebellion.com/footage_calc.htm



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Matt Press
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 5:51:45 pm

In FCP, I can export to "Blackmagic NTSC IMX MPEG (50 Mb/s)". Is this right?

The client is looking for:

Video:
MPEG2,
NTSC,
720x480 resolution
50 Mbit CBR,
i-frame only, no GOP,
16:9 content should be anamorph 720x480, no black bars or picture boxing,
we prefer 16:9 versions of the content!
Audio:
best Audio you got

Each film is 90 minutes. I would be getting the films on a hard drive rather than Digital Beta, so no capturing would be necessary.


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Daniel Low
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 6:37:13 pm

That might work, you should send a test file to the client to see if it's compatible, I'm not sure if they'll need the Blackmagic Codecs.

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Please post back saying what solved your problem. It could help others, and saying 'thanks' is free!


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Matt Press
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 7:00:40 pm

I exported a file using this method, and though Movie Inspector said the data rate is 50 MB/s, the Final Cut time line said the data rate was 6.3 MB/s, and one minute of footage is only 400 MB. Am I missing something?

-Matt


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Chris Blair
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 7:19:48 pm

I believe the MPEG2 50MBps spec refers to MegaBITS per second and not MebaBYTES per second. So if you add the audio into the data rate, that sounds right.

Uncompressed SD video averages about 21 MegaBYTES per second for 8 bit, and 27 or 28 for 10 bit regardless of the codec.



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


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Daniel Low
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 7:34:11 pm

Mb = Megabit
MB = MegaByte

1MB = 8Mb

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Please post back saying what solved your problem. It could help others, and saying 'thanks' is free!


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Daniel Low
Re: MPEG-2 @ 50 MBps
on Feb 10, 2009 at 7:45:52 pm

525 NTSC uncompressed;
8 bit @ 720 x 486 @ 29.97fps = 20 MB per/sec, or 70 GB per/hr.
10 bit @ 720 x 486 @ 29.97fps = 27 MB per/sec, or 94 GB per/hr.

625 PAL uncompressed;
8 bit @ 720 x 576 @ 25fps = 20 MB per/sec, or 70 GB per/hr.
10 bit @ 720 x 576 @ 25fps = 26 MB per/sec, or 93 GB per/hr.

IMX/MXF MPEG-2 I-Frame audio is typically Linear PCM at 48K, 1526Kbp/s for 2 channels

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Please post back saying what solved your problem. It could help others, and saying 'thanks' is free!


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Matt Press
Re: MPEG-2 @ 50 MBps
on Feb 11, 2009 at 3:47:05 pm

Makes total sense. Thanks.

-Matt



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Andy Mees
Re: MPEG-2 @ 50 MBps
on Feb 15, 2009 at 1:12:54 am

MXF4Mac's MXF Export may be worth a look for you Matt, it works a treat.
http://mxf4mac.com/mxf4qtexport


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