BWF/iXML AMA Update (v8)


There has been a thread on the Avid-L discussing BWF import and AMA linking and I was surprised to read in that thread that the AMA BWF/iXML Media Composer 7.0.4 now supports monophonic BWF files as a single clip. before this release it was only supported by import. I did not see this in any of the READ ME’s but is a nice add to the AMA functionality.

But… there are still trade-offs to consider between AMA and import that need to be considered when dealing with monophonic files. The following graphic shows the different results when importing or linking and how support for metadata changes depending on method chosen (click for full size)


The first thing is a bug that has cropped up in v8 where importing monophonic files and creating a single clip upon import does not have the right duration. Basically the imported duration (X) end up being: X = (BWF duration)/n  where n is the number total number of tracks being imported. As seen in the import, what should have been 2:27:00 in duration ended up being 18:09. While we can expect this to be fixed in a updated version, hopefully it will also include the track metadata that gets lost in tracks 5 and higher when importing polyphonic files.

AMA linking to the monophonic files works as mentioned, but does not parse any of the track metadata on and of the tracks. There is no workaround for this as there as  an option to link and maintain individual tracks does not exist with AMA as there is with “Import”. There is also some inconsistencies with source metadata between Source File and Tape ID on the AMA linked version that may affect EDL and such downstream.


For now, the best method for monophonic files is to import them as individual tracks, then select all the tracks in the bin and select AutoSync as seen in the bottom bin of the above screenshot. No need to AutoSequence them first as mentioned in the Avid-L thread, and multiple takes can all be done in one pass. The one downside to this method, is using matchframe to get back to alternate tracks from the sequence. For example, the 8 track clip in the example has a mix track on 1 and 2. AutoSync allows for any consecutive span of tracks to be used in the resulting .sync clips such as 4-6, or in this case 1&2. What is very helpful when editing is the ability to do a double matchframe back to the 8 track clip to use an ISO track instead of the mix track. This is done by match framing on the sequence which loads the .sync clip. Then, from the sequence side, turn off the V track and matchframe again on the source side and it will load the multitrack audio. When synced from a polyphonic file, or a single clip created from multiple mono tracks, it gets loaded at the same position for easy track and position selection. In this scenario, it will only load the original single mono track and not the synced group defeating the purpose of this feature.

Another workaround is to combine the monophonic files into a single multitrack polyphonic file. There are several applications that can do this, but this is easily done with Sound Device’s free application Wave Agent  available for both Windows and OS X. Here is the result of combining them, and then accessing the file via the BWF/IXML AMA Plug-in. (click to enlarge):


As always, plan your workflow accordingly. If there is no additional track metadata logged or needed,  then AMA may be the best route to take, if there is, import is the better way to go. When it comes to audio, it is so fast to import, that the instant access is not that much of a benefit as found with video formats. I would love to see a metadata view available in the AMA window selecting the BWF files displayed in the window, then do an “import” versus a link at that time rather  than the potential additional steps of transcode or consolidate with more clip management needed. Then create a “container” type file that managed all the tracks with the ability to define as mono, or stereo (or more). Once edited in the timeline, it would be a simple right-click to activate the ISO track(s) needed for that event. This would offer the best of both worlds.

Update 8/9/14:  Version 8.1 has fixed the duration issue when AMA linking to monophonic BWF files, but track metadata is not supported at all.

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