QT DNxHD - what happens during the import into Avid?

[Gustav Gans]

cause it seems like there is no possible workflow after an avid-editing to go back to the r3d-files, i'm trying to get the best quality into the avid. I did QT-Files using the DNxHD-Codec and imported the whole stuff. But what is the Avid doing?

• Is it a transcode or a new encoding?
• Do i have any further losses?
• Or is it just a conversion into mxf-Files?

any ideas?
Tobi

 

[Dylan Reeve]

If you've used Metacheater to set metadata correctly on the clips you've imported then there should soon be a path back. MichaelP has said Avid is working on a translation tool to make REDCINE XML files from an Avid edit.

There are a variety of reasons why this is difficult however.

As yet there is no clear and automated workflow from Avid edit to .R3D reconform.

This is further compounded by the fact that REDCINE seems to fail to get the 25fps timecode info from the clips, assuming instead they are 24fps. This means that even if there is a reverse workflow it's likely that timecodes and durations on 25fps material will be a little out of whack.

Right now the only way is manual reconform.

 

[Jeff Brue]

Ew manual conform. Automatic duck to final cut to red cine.

 

[MichaelP]

There are a lot of questions here...

What is Avid doing during the import? Depends on how it is coming in. If you are importing from the QT references directly, it is decoding via the QT and then encoding once to the DNxHD resolution of your choice. If you are encoding as DNxHD directly via RedCine, it is encoding to DNxHD 115 (no choice at this time, but coming soon). That process does the same process as the import but outside the Avid editing application. When you import that into the Avid, there is no farther decode/encode but a rewrapping of the file into MXF from QuickTime.

Conform is based on the metadata back out. If you use MetaCheater, it will gather the Reel ID and timecode and create an ALE file. The ALE is imported first, then the QT's are merged into that so it inherits all the metadata. There is work being done to create ALE directly from the Red tools as well as Avid delivering XML From/To Redcine. Today you can make an EDL if you first imported via the MetaCheater method.

I put together some steps on this process which will be posted on StudioDaily.com later this week. Once there I will post a link.

XML and other solutions will be available in the near future.

Michael

 

[Sean]

Looking very forward to the StudioDaily article, Michael.

So is a DNxHD created in Avid from an .r3d QT proxy currently better quality (ie., you have the choice of DNxHD 175) than a QT DNxHD file created by RedCine and imported into Avid (limited to DNxHD 115)?

Is there any other way to get DNxHD 175 into Avid from r3d files in the meantime? Perhaps exporting a TIFF sequence from RedCine (that could be giant) and then importing that into Avid (which transcodes to DNxHD 175)?

Thanks!

 

[MichaelP]

Currently you can create a better quality by importing the proxy to 175x (10 bit) than 115. But that will soon change once the Red tools get access to the full set of DNxHD codecs as well as uncompressed 10 bit for Avid.

Certainly 10 bit TIFFs will work, but will take up some drive space during the interim process.

Michael

 

[Sean]

I do get banding when I try to take the DNxHD 115 out of RedCine and do some minor color correction in Avid Media Composer. I'm going to try a TIFF sequence with the exact same color correction.