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Strobe Media
03-01-2010, 01:23 PM
ok I have a problem, first of all, I'm editing on a PC in PP CS4 with the 7D

I downloaded that Avid thing to get the preset of NDxHD. Only thing is, when I export from Mpeg Streamclip as .avi, and bring it into premiere, it doesn't recognize any video! I followed all the steps, but it just shows that it's an audio file.

So i tried exporting as .mov with the same preset and steps, but when i render my work field, it makes the clips all dark!

any help?!

ydgmdlu
03-03-2010, 01:05 PM
When you say "dark," do you mean darker or completely black?

There might be a gamma profile issue at work here.

FixMix
03-08-2010, 12:34 PM
Any news on this issue? I am going to buy a 7D and work on a PC basis right now. I'm still not sure what I am going to encounter workflow-wise?

Can anyone give me a heads-up?

PerroneFord
03-08-2010, 12:43 PM
This is not an issue properly done. I've done it hundreds of times.

First order of business, DNxHD doesn't go in an AVI container. It's an MOV container, as it's a quicktime codec.

Second, the encoder gives you a radio button to select whether or not the source file is REC709/REC601 or RGB. You choose the appropriate selection and everything goes smoothly.

ROCKMORE
03-08-2010, 03:54 PM
This is not an issue properly done. I've done it hundreds of times.

First order of business, DNxHD doesn't go in an AVI container. It's an MOV container, as it's a quicktime codec.

Second, the encoder gives you a radio button to select whether or not the source file is REC709/REC601 or RGB. You choose the appropriate selection and everything goes smoothly.

Hey Perrone, I finally got a T2 today and have been reading your workflow systems for a while. I can't seem to find your earlier threads. Do you have a link to one of them so you don't have to go over it a millionth time. I set us an i7 PC with CS4.

Thanks.

PerroneFord
03-08-2010, 05:44 PM
Hey Perrone, I finally got a T2 today and have been reading your workflow systems for a while. I can't seem to find your earlier threads. Do you have a link to one of them so you don't have to go over it a millionth time. I set us an i7 PC with CS4.

Thanks.

You'd think I would have saved it on a disk somewhere! And my workflows change depending on need. Occasionally, I do just drop the thing in the timeline. But usually I convert to DNxHD with Mpeg Streamclip, and bring that in on the timeline.

If you can afford it, buy Cineform's NeoScene. It will generally make your life much easier.

ROCKMORE
03-09-2010, 10:20 PM
You'd think I would have saved it on a disk somewhere! And my workflows change depending on need. Occasionally, I do just drop the thing in the timeline. But usually I convert to DNxHD with Mpeg Streamclip, and bring that in on the timeline.

If you can afford it, buy Cineform's NeoScene. It will generally make your life much easier.


I looked on Google and there it was. 10 pages, reads like Gone With The Wind.

http://www.dvxuser.com/V6/showthread.php?t=195394

I'll check back when working. I download the DNxHD zipped file last month but the Mpeg Streamclip link I found on Google seems to be from 2008, is there a newer link?

I really only care about the highest quality. I will suffer along with anything I have to, if it has better end result.

For the record. It's a 550D and I'm in Pal territory with CS4, (Premiere, AE, Photoshop) and a new i7 PC. The export will output to Pal 25fps, BlueRay asap. Just finished an EX3 project on the i7 and it went smooth as silk.

Thanks

PerroneFord
03-10-2010, 04:48 AM
Yes, that's the right Mpeg Streamclip version. I guess it's a somewhat abandoned product.

If you are after best quality, then forget Mpeg StreamClip and just transcode to Lagarith. It's lossless. DNxHD is excellent, but it's not lossless. Neither is Cineform.

ROCKMORE
03-10-2010, 08:08 AM
Yes, that's the right Mpeg Streamclip version. I guess it's a somewhat abandoned product.

If you are after best quality, then forget Mpeg StreamClip and just transcode to Lagarith. It's lossless. DNxHD is excellent, but it's not lossless. Neither is Cineform.

I just shot some tests and imported them to CS4. It plays smooth enough to screen and select rough takes, better than I expected. I exported the trimmed clips to an uncompressed Quicktime file at 12 GB per min. This works pretty fast and I don't have to transcode all the footage, just what I select. Then I can save the select project to refer back to if I need a longer clip later.
Is there any advantage to Lagarith over Uncompressed quicktime?

PerroneFord
03-12-2010, 11:57 AM
Is there any advantage to Lagarith over Uncompressed quicktime?

Takes less disk space. That's about it.

ROCKMORE
03-18-2010, 05:10 PM
Takes less disk space. That's about it.

Perrone, how big are these DNxHD transcoded files once they have been converted. The Uncompressed Quickitme is 12 GB per minute / 10 bit is 8GB per minute / 8 bit is 6 GB per minute. How much space does it consume?

PerroneFord
03-18-2010, 05:23 PM
DNxHD is not a fixed target. There are at least a dozen different bit rates that are available. The least of which is about 36Mbps, or 8MBps. That one takes about 16GB/Hr... the same as my EX1. The top rate is 220Mbps, which is about 1.65GB per minute. So about 8:1 over Uncompressed 10bit.

ROCKMORE
03-19-2010, 08:41 PM
DNxHD is not a fixed target. There are at least a dozen different bit rates that are available. The least of which is about 36Mbps, or 8MBps. That one takes about 16GB/Hr... the same as my EX1. The top rate is 220Mbps, which is about 1.65GB per minute. So about 8:1 over Uncompressed 10bit.

What would you think the quality difference between the DNxHD conversions and full uncompressed Quicktime at 12 GB/minute?
Not from a general view on an HD Monitor, but from close examination from the pixel peepers here on this site.
The quality from the DNxHD probably looks about the same most of the time, but for short projects such as 30sec commercials it may be better to go uncompressed. Even though it involves huge files, it is still a smooth solid work flow.
At least it's worth doing a test comparing the 2 methods just to know where we stand.

PerroneFord
03-19-2010, 08:58 PM
What would you think the quality difference between the DNxHD conversions and full uncompressed Quicktime at 12 GB/minute?
Not from a general view on an HD Monitor, but from close examination from the pixel peepers here on this site.

Avatar, Transformers, Ironman, etc., were cut in DNxHD. I think it will be fine for your 30 second commercial.

PerroneFord
03-19-2010, 09:02 PM
At least it's worth doing a test comparing the 2 methods just to know where we stand.

I've done dozens of test, done difference histograms and waveforms, using most flavors of DNxHD vs. original, using DNxHD against lossless, using it against Jpeg2k, against other codecs. It holds up fine, and I'd use it for any feature without worry. Heck, I have projected the proxy variant without issue. In fact, I was inspired to do so after reading that is how the Ironman rough cut was screened. I read early this year that Avatar was also screened using the proxy variant.

ROCKMORE
03-20-2010, 03:11 PM
I've done dozens of test, done difference histograms and waveforms, using most flavors of DNxHD vs. original, using DNxHD against lossless, using it against Jpeg2k, against other codecs. It holds up fine, and I'd use it for any feature without worry. Heck, I have projected the proxy variant without issue. In fact, I was inspired to do so after reading that is how the Ironman rough cut was screened. I read early this year that Avatar was also screened using the proxy variant.

Sounds too good to be true, but so is the 550D and all these new cameras so I am a believer. I have the DNxHD zip file and will get the Streamclip downloaded. Do you have any links to articles on Avitar and Ironman, I'd like to read up on them.
Thanks

PerroneFord
03-20-2010, 03:33 PM
Do you have any links to articles on Avitar and Ironman, I'd like to read up on them.
Thanks

Here is the Ironman link:

http://digitalcontentproducer.com/mil/features/video_dnxhd_marvel/index.html

Let me look for the Avatar one.

I couldnt find the link I wanted.. but here's one from Weta Digital who did a lot of the post work on Avatar:

http://www.avap.com.au/index.php?sectionID=7&catID=&articleID=558

ROCKMORE
03-20-2010, 10:32 PM
[quote=PerroneFord;1935971]Here is the Ironman link:

http://digitalcontentproducer.com/mil/features/video_dnxhd_marvel/index.html

/quote]

Great read, I'm sold.
Thanks Perrone