To add an additional quadry to this. the masterfile mxf that links to the sub mxf files in the media folder breaks up the stereo pairs of audio from the mxf audio file media folder. For example the A04 mxf audio file is a stereo pair of silence but when the master mxf file is linked in Avid the two silence tracks are separate from each other in not contiguous tracks, something like one silence on track 4 and another on track 9. When I take the individual mxf files in the media folder and link to them then auto sync them then audio pairs are contiguous but the track order does not follow from _a0 to _a5. I haven't bothered to figure out what order they end up in but I'm curious what determines the order of the audio tracks in an auto sync clip. Is it bin order or some other thing? I do see the tracks that are mxf _a3 thru _a5 in the auto sync clip end up as clip tracks 1 thru 6 but it appears there order is _a5 becomes clip tracks 1 and 2, __a4 becomes clip tracks 3 and 4, and the _a3 becomes clip tracks 5 and 6.
Not only should they be tracks 7 thru 12 but even there numeric sequence is reversed in order. This leads me to think there is some other than suffix of the clip names creating the order. Is there some other subtle metadata in the food chain that tells avid how to order them.
It's hard to figure what's dictating what as the auto sync of the individual clips based on source code yields a vastly different track order than that of the master mxf file that links to the individual clips in a bizarre order. This sounds like a VideoToolShed question.
---In Avid-L2@yahoogroups.com, <bigfish@...> wrote :
Been working on a workflow test with a network. They provided AvidMedia Files and bin for the test clip to export as jpeg2k mxf. There is a complaint about the 5.1 audio stems loudness. This is a clip from a show master so everything is just going through as unity on my end. It seems the source material is off to begin with. There are 12 tracks to the clip two of which are silent as per spec. I don't have a loudness meter but using infinite hold I see all the tracks are peaking around +3db with the exception of the Lfe which is lower and the stereo M&E which is hitting 0. The complaint is on the discrete 5.1 tracks and not on the stereo mix tracks all of which peak at the same levels on infinite hold.
I know that peak level is different than loudness. I assume loudness is more the dialogue norm type spec they are sighting. We are trying to clarify with the network. When I do a test with bars and tone everything comes out at correct level so I'm convinced I'm not doing anything other than passing things through at unity. If there were audio tracks being multed I would expect to see far different track overshoot than I am.
The network also gave us an mxf file of the entire episode. I'm not sure what it was created in but there is a "master" .mxf then in a sub folder are individual .mxf files for video and 6 stereo audio tracks and a vanc track. The master file is "xmn1792625.mxf" then there is a folder named "media" that contains "xmn1792625_v0.mxf". "xmn1792625_vanc0.mxf" and 6 audio files "xmn1792625_a0" with the additional audio files changing the suffix to a1-a2 etc... for a total of six stereo tracks.
In Avid I can link to the master file or the individual files. When I first linked to the master file it showed offline in Avid but when I started to link to the individual media files it popped online. This file includes bars and tone which play back correctly but the audio tracks are in a whacky order. This file show the exact same audio peak that I'm experiencing with the avidmedia files the network provided. All I can see is I'm passing things through at unity and it seems the mix we were given is off. More will be revealed on this
I'm curious if anyone knows what software creates master .mxf files that point to subfoldered media files. When I export my .mxf J2k file Avid creates a single file that has video and audio tracks. Whatever this file came from the structure is different. There is also a "manifest.xml", "shim.xml" and an "extra folder that contains an "amberfin.com" folder that contains some QC stuff I guess. Does this point to this master mxf file coming from an Amberfin server thing? Or is this something Premiere might create. Just trying to play along with the network.
John Moore Barking Trout Productions Studio City, CA bigfish@...
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