ADOBE PREMIERE PRO: Tutorials Forum Articles Podcasts Basics Forum Creative Cloud Debate

Best Format for Masters

COW Forums : Adobe Premiere Pro

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Alexander PerlmanBest Format for Masters
by on Feb 25, 2015 at 7:34:44 pm

Dear community,

I'm outputting masters for several hundred videos. The video engineer recommended that we use DNxHD instead of ProRes because all of the edit stations here at PCs.

The problem is that a lot of the files that I'm bringing into AME have bitrates of 25-50mb/s (we received a lot of videos from outside editors). Using DNxHD I wind up exporting files with much higher bitrates that take up a lot more space...seemingly for no reason.

Do you guys have any suggestions on how to decrease the DNxHD bitrate to match the input or am I locked into the presets in the "codec settings" pop-up? Also, is there a superior format besides Pro-Res?

Return to posts index

Declan SmithRe: Best Format for Masters
by on Mar 3, 2015 at 5:52:56 pm

I'm surprised there is a lack of response to this question as creating masters is fundamental, unless of course you have more storage than video files!

Other than setting lower resolutions and bit depth (and foregoing sub-sampling) I don't think there is a way of getting smaller files with DNxHD.

With regards to creating masters, I have faced a similar issue in that I normally master in ProRes, but due storage limitations, I would prefer to store archived masters in another format so as to retain the highest quality possible with smaller file sizes and better cross platform compatibility. I have done some looking into this and there are a number of formats used for broadcast, of which support 4:2:2 sub-sampling. I share below an example of some tests I have done as a comparison use Adobe Media Encoder. These are based on a HD 1920x1080 25p source project which is 3m27s.

PhotoJPEG (4:2:2): 5.6Gb
ProRes (4:2:2): 2.7Gb
DNxHD (4:2:2): 4.4Gb

MPEG-2 (4:2:2 50Mbps): 1.2Gb
MPEG-2 (4:2:2 30Mbps): 770Mb
XDCAM (4:2:2 50Mbps): 746Mb

Normally, I would walk away from MPEG-2, but at 4:2:2 and 50Mbps, I must admit it's visibly hard to tell any difference between the results, but I have not compared post work on the new master files (for example, pulling keys or colour grading). XDCAM is a specification I have seen as a standard broadcast mastering codec (also MPEG-2 based).

Declan Smith
After Effects CS6/ FCS3 / Canon XLH1 / Canon 7D / Reason / Cubase

"it's either binary or it's not"

Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2016 All Rights Reserved