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I have a feature film exported at PRO RES - How can I convert it to H264?

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Alex Petrovitch
I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 12:59:59 am

Hey forum,

I have a feature film exported at PRO RES. I need a H264 version. I tried exporting from FCP7 to H264, I chose "BEST" quality for compression, and it's 69GB. (Every other time I've exported features, I used "good" at they are always under 10GB)
I could just reexport from FCP7, trying "good", but I was wondering if I could take a PRO RES HQ version and convert to H264, instead of reexporting from FCP7?

I usually use MPEG to transcode from H264 to PRO RES to edit Canon EOS Material, which makes the files much bigger. (As expected) But I tried converting PRO RES to H264 using MPEG, and the file size stayed the same. Huh?

Thoughts?

Alex Petrovitch
http://www.markwoodfilms.com
2013 iMAC 3.4 Quad Core i7, 32GB RAM, 3TB Fusion
FCP7/CS6/AVID
Canon 7D&5Dmk3
Panasonic HVX200


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Craig Seeman
Re: I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 1:47:47 am

file size = data rate x duration.
With minor variation it's that simple.



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Alex Petrovitch
Re: I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 1:51:09 am

Hmmmm....
Maybe I wasn't clear. I was looking for a workflow to convert an exported PRO RES file to H264, w/o having to re export from FCP7, not definitions of things. Sorry if I wasn't clear!

If anyone in the forum has a suggestion, it'd be much appreciated!!!
Best,
Alex

Alex Petrovitch
http://www.markwoodfilms.com
2013 iMAC 3.4 Quad Core i7, 32GB RAM, 3TB Fusion
FCP7/CS6/AVID
Canon 7D&5Dmk3
Panasonic HVX200


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Craig Seeman
Re: I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 1:54:51 am

You seemed to be concerned about file size.
Just adjust the data rate when exporting from FCP7.

If you want to use the ProRes version without using FCP7 just use Quicktime Pro or Compressor.


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Alex Petrovitch
Re: I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 1:59:33 am

Thank you Craig. I was just wondering if there was a workflow now that I have it already out of FCP7 using MPEG. Reason being, the export of a H264 file for a 90 minute feature takes over 8 hours on my current system and I thought/think transcoding would be faster than starting again.

However, if I can't, I will calculate the necessary data rate/size etc equation that you suggested. I'm guessing I don't want to go below 5000kbps to maintain a nice sharp HD image.

Alex Petrovitch
http://www.markwoodfilms.com
2013 iMAC 3.4 Quad Core i7, 32GB RAM, 3TB Fusion
FCP7/CS6/AVID
Canon 7D&5Dmk3
Panasonic HVX200


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Craig Seeman
Re: I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 2:09:07 am

[Alex Petrovitch] "I was just wondering if there was a workflow now that I have it already out of FCP7 using MPEG."

MPEG as in MPEGStreamClip? Sure that would work as well.

[Alex Petrovitch] "the export of a H264 file for a 90 minute feature takes over 8 hours on my current system and I thought/think transcoding would be faster than starting again"

Compressor with QMaster might be a little faster but then again it might depend on your system and the number of cores.

[Alex Petrovitch] "I'm guessing I don't want to go below 5000kbps to maintain a nice sharp HD image."

It can depend on content (complexity, fast motion) but 720p can range from 2000kbps to 5000kbps. You can push it a bit higher for 1080p.

An interesting thing to do is go to YouTube, find a video that plays and 1080, play and right click and select video info and it'll tell you what data rate they're using. Not that you need to match it but it does give you a base to compare the data rate you might choose.



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Jeff Greenberg
Re: I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 11:04:52 am

[Alex Petrovitch] "I have a feature film exported at PRO RES. I need a H264 version. I tried exporting from FCP7 to H264, I chose "BEST" quality for compression, and it's 69GB. (Every other time I've exported features, I used "good" at they are always under 10GB)"

The QuickTime export from FCP done like this 'auto picks' a data rate - which is why this was so large. Generally, I don't like the "Good" or "Best" because these are arbitrary settings - I've never done the research to figure out what it picks - but it's never 'great' at a small size. It's usually HUGE and looks okay.

[Alex Petrovitch] " I could just reexport from FCP7, trying "good", but I was wondering if I could take a PRO RES HQ version and convert to H264, instead of reexporting from FCP7?"

I suggest to most people to do exactly this to make a 'master' copy of their work (in ProRes.) You can now take this file and encode it (again) to h.264 or whatever your needs are. The ProRes quality is considered to be mezzanine worthy - great for later reuse like this. Minimal damage. Toss this at MPEG Streamclip, Compressor or your given compression tool of choice.

[Alex Petrovitch] " I usually use MPEG to transcode from H264 to PRO RES to edit Canon EOS Material, which makes the files much bigger. (As expected) But I tried converting PRO RES to H264 using MPEG, and the file size stayed the same. Huh?"

Footage that comes off your Canon camera is about 50 mb/s. ProRes 422 is about 140mb/s. Your files should balloon up about 3x in size. BUT if you convert from ProRes to h.264 using the method you started with (The Best or Good setting) who knows what you'll get? The data rates are arbitrary. This is why the files were so large - because the 'Good' or 'Best" arbitrarily picked a data rate near ProRes's standard data rate.

Best,

Jeff I. Greenberg
Author/Master Instructor/Speaker/Consulting
My contact info and more
New! Come see me speak @ NAB/Post Production World!


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Alex Petrovitch
Re: I have a feature film exported at PRO RES - How can I convert it to H264?
on Mar 27, 2013 at 5:37:53 pm

Jeff,

Thank you for the in depth response. I'm almost there. The PRO RES export that I have is the "current settings", so there is no compression. It's full res, 422 HQ. So I will compress from that copy using MPEG Streamclip, to avoid what you described using FCP7's ambiguous "good" / "great" settings with regard to data rate.

Now. In MPEG Streamclip, what data rate do you suggest? I did a demo this morning of a small 2 minute file, set it to 5000kbps, and the data info showed 6.30 Mbit/s. That is well below the 50mb/sec which you illuminated that Canon EOS cameras record at. 50mbs, would be 50000 kbps, right? That seems like I'd have an uber big file. What data rate do you suggest? The 5000kbps looked high quality, but do you think that is too low.

Second, last question, and this is simple. In MPEG streamclip, when you opt to "limit data rate", there is a drop down menu. There are 4 choices. KB/sec, MB/sec, kbps, mbps. I was thinking that KB/sec meant kilobites/sec. But I also thought that was kbps??? When I threw in the 85 min file, the estimated size at 5000Kbps was 3.6 GB, but the estimated file size for 5000KB/sec was 25GB. Thoughts?

thank you again for all of your specific advice and knowledge.

Alex Petrovitch
http://www.markwoodfilms.com
2013 iMAC 3.4 Quad Core i7, 32GB RAM, 3TB Fusion
FCP7/CS6/AVID
Canon 7D&5Dmk3
Panasonic HVX200


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