BWF Import, not quite there yet...

Question

Hi there,
I just downloaded the 5.1.2 update and was quite excited by the new (at last) BWF import feature. So the first thing I tried was to import some BWF files to see how it works. The files I have at hand are BWF, Polyphonic files, with 24fps Timecode. They were originated with an Aaton Cantar and polyphoniced' using Majax.
I have to say that I'm not impressed:
- The resulting Clip in the browser has a 25fps TimeCode. It cant' be changed.
- The sc/take info, as well as the info typed in by the sound recordist don't appear in any of the columns.
Am I doing anything wrong?
Pierre

Answer 1

Hi Pierre,
I think unfortunately the BWF support announcement makes it sound a little better than it actually is. Its a good step, but there is by no means full BWF support in 5.1.2. For a really detailed intro to what's going on here is a post from Andreas Kiel (who develops BWF2XML):
Hi all,
One of the new features in Final Cut Pro 5.1.2 will be enhanced QT metadata support and
support for the Broadcast Wave Format. (More informations about BWF can be found at the
EBU Website.)
As I did one of the (living) applications to integrate BWF into a FCP workflow I got a lot of
questions from users and potential user about the "BWF compatibility" feature in FCP 5.1.2
and how BWF2XML compares to the options in FCP.
Some additional information about uncompressed/HD/film workflow and audio can be
found at:
http://www.apple.com/finalcutstudio/resources/white_papers/L328398A-
USL328398A_HD_Workflow_FilmTV_FCPwp.pdf#search=%22L328398A-
USL328398A_HD_Workflow_FilmTV_FCPwp.pdf%22
Introduction:
Beside all the other improvements with this new version of Final Cut Pro, one of the big
improvements is that this new version makes extensive use of all the new QuickTime
structures, allowing QuickTime metadata access and tc64 timecode (which is audio
timecode). This last feature has been tested with a lot of different files, and nearly all files
with tc64 information showed up correctly.
The QuickTime metadata access will allow third parties to create QuickTime components
with metadata - like the DPX/Cineon component from Bob Monaghan at GlueTools, the
first of it's kind. This will also allow other companies to create a QuickTime components
for MXF, IMX etc., and you'll be able to drag a MXF (or something like that) to the timeline
with all the metadata included. So stay tuned for future announcements from third parties.
tc64 audio timecode is something new in QuickTime:
QuickTime is interpreting the BWAV header entry for the samples after midnight - most of
you (at least those who are interested) can already check that: just open a BWF file in
QuickTime Player Pro (7.1.3), press cmd-J and enable the TC track. You'll see the samples
after midnight (don't save when closing the file).
Final Cut Pro now makes use of this this QuickTime feature, and creates a timecode based
on the tc64 samples after midnight and the sampling rate. This will result in seconds after
midnight. The seconds can be converted to timecode by extracting hours, minutes,
seconds and partial seconds, where partial seconds will be converted to frames based on
the timecode base.
The timecode base is complicated to figure out, since mostly it's not written to the header
of the BWF file. And even if it is, QuickTime won't interpret it, since it is nearly impossible
to automatically interpret all the ways the header is set up. There maybe other information
in the header like reel, scene, take, note etc. However, this currently won't be interpreted
by QuickTime as well. As opposed to a QuickTime timecode track, reel information is not
kept in a tc64 track. So if QuickTime doesn't interpret it, Final Cut Pro can't either, and for
the timecode, it will probably take the current timecode base of the project, which might
differ from the original sound recording.
With audio, there are also things like 29.97 NDF (which is not available in Final Cut Pro
right now), and the samples after midnight also may be based on either real world seconds
or NTSC seconds. Plus, there may be playback instructions in coding history. All of this is
quite a complicated thing, and it will be left to the user to think about the setup in
advance.
File formating and appearance:
BWF can show up in either polyphonic or multi-mono format. Both of these formats do
have advantages and disadvantages.
Polyphonic files are easy to handle. As all tracks are included in one file, they are faster on
transfer from the audio harddisk recorder than mono files. Polyphonic files are also easy
to import with the new Final Cut Pro feature. They have the disadvantage that removing
unused tracks is difficult when it comes to exchange with other audio workstations or
when using XML and reconnect, since they are interleaved.
Mono files take longer when transfer from the audio harddisk recorder since the de-
interleave has to be done prior to transfer. They also have the disadvantage that they can
only be imported as discrete files, and need to be connected "channel by channel" within
Final Cut Pro, which makes the process much more tedious. The big advantage of using
mono files though is, that you can remove (or even add) channels and will have no
problems when doing an interchange with DAWs, via XML, or with content management
systems. The channel files can be handled by Media Manager up to a certain extent when
left untouched, or fully when converted to a .mov format.
More detail about the two kinds of timecode tracks:
The QuickTime timecode tracks we are used to working with behave, let's say, just like
another "movie" track, so you can step thru frames.
tc64 reads the timestamp of an BWF audio file - this happens only once, so it behaves like
a long frame, which can't be stepped thru by samples, frames, seconds etc. It's just one
frame when activated - even though it shows the samples during playback.
The QuickTime timecode track forces a file into a specified playback behavior, which is
user-defined, and even can be changed within Final Cut Pro (within certain limits). It can
also be used as AUX TC in synched clips.
tc64, when used in QuickTime/Final Cut Pro, just gives a reference which relies on the
sample rate to get the time. To change the playback behavior, you need to change the
sample rate "virtually". This means that the file's samples are not changed but the "this file
is sampled at" description will be changed. This can be done with a third party application
outside of FCP (this is our current info about changing playback, and it might be wrong).
As said above, with QuickTime timecode there is timecode timebase and reel info, with
tc64 there can't be timecode timebase and reel info.
What about bringing BWF2XML and the new QuickTime/Final Cut Pro features together?
This should work cool, since Final Cut Pro 5.1.2 will accept the tc64 for first time ever, and
BWF2XML can supply you or Final Cut Pro with the additional metadata without converting
to QuickTime timecode (though there are still a lot of advantages doing that).
But it needs some additional steps done with BWF2XML, like changing playback settings to
apply pull-up or pull-down. If that's done, BWF support in Final Cut Pro will be exceptional
compared to other NLEs, and conversion will be lightning fast - even if there is no direct
import plug-in for this "combined" import. With the new XML version 3, things may
become easier and BWF2XML may work as a pseudo importer plug-in.
Conclusion:
So why do I write all these mostly "negative" things (about FCP)?
Pretty simple, since working with these relatively new formats and devices isn't that simple
for most video and postpro people.
Apple made another big step into the tapeless future, as well as some of you who made
this step using "new" devices and formats. With new devices there is always the problem to
establish something like a "common sense" for set up and workflow, which doesn't exist
right now.
So if a BWF import into Final Cut Pro would give you an erroneous result, don't blame
Apple and don't start threads about blaming Apple, they made the above step, and they
too will probably run into similar problems as any of the other companies - like me - who
are dealing with BWF, machine setup, file setup and naming as well as user setups.
Other companies just restrict, maybe by the amount of channels, maybe by the titles/
names of metadata entries, maybe by kicking out metadata entries - and still the other
companies look to be a little bit ahead.
Regards
Andreas
http://www.spherico.com/filmtools
Hope that helps,
Mark