Things to consider when designing your workflow

Which Export Format ?

XMLPro can convert into either Pro Tools sessions, or AES31 ADLs. Your choice of workstation may determine which of these you choose, but you should be aware of some subtle differences in the conversion process for the 2 file types.

Pro Tools Session.

The XML to Pro Tools conversion maintains all level information from Final Cut Pro, including both clip levels and keyframe automation. These are converted into volume automation graphs for the new tracks created in the session. However, due to a Digidesign limitation, crossfade regions cannot be converted from the XML into the Pro Tools session. Instead crossfades will be converted to splice edits. The Pro Tools session technique supports Mono SD2, AIF or WAV files as source media in the Final Cut Pro sequence.

AES31 ADL

The AES31 ADL format is becoming extremely common and can be read by a variety of different audio workstations including Steinberg Nuendo. The XML to AES31 conversion maintains Clip level information from final cut, but due to a limitation in the AES31 ADL format, it is not possible to communicate keyframe automation. In these cases, the first level found in a given FCP clip will be used as the clip level communicated through AES31, and subsequent keyframes in that clip will be ignored. Crossfades are maintained through the AES31 conversion. Note that the AES31 specification implies the use of broadcast WAV files, and so you would normally expect to use these as source media in the final cut Pro sequence. However there is no technical reason why this process could not also support SD2 or AIF files, so this implementation will depend on whether the target audio workstation is willing to accept an AES31 ADL which references non-WAV media. Although AES31 does support multichannel audio files, XMLPro does not currently support this. This situation may change in a future release if there is sufficient demand for multichannel media support.

Mono files required in Final Cut Pro

Since the XMLPro conversion creates an output file which references the original source media, it is vital that the media files used are ready and compatible with the audio workstation your are targetting. For a Pro Tools system, this means that your audio files MUST be mono SD2, AIF or WAV files, since these are the only file types supported by Pro Tools. When creating your Final Cut Pro sequence, you need to make sure that your audio is prepared accordingly, since no media conversion will take place in XMLPro. Special care should be taken when importing music, or sound effects to use split stereo files (ie. a separate file for Left and Right channels). Contact Gallery for advice on tools to make this process easier. Also, XMLPro cannot support audio which is embedded in a video QuickTime movie, such as a DV file. The main application for XMLPro is in a typical movie workflow, where a location disk recorder will be capturing the sound from the set, as Mono broadcast wave files, whilst the picture is stored on Film or Video tape. Later, after telecine (in the case of Film), the editor will sync the audio dailies with the digitised telecine, creating clips which connect the picture media, and the (several) mono audio files. This workflow is VITAL if you want things to progress smoothly through audio post, especially if you want to use MetaFlow later on. For workflows where this is not practical, but which would still benefit from translation of volume automation, a Hybrid OMF/XML workflow can be used (see below).

Hybrid OMF / XML Workflow

The requirement for Final Cut to use Mono audio files in an XMLPro workflow may not be suitable for all situations, particularly where the project has already begun, using embedded audio media. In these cases, you can use a hybrid approach to get the best of both worlds, twinning the audio media conversion functionality in OMF, with the volume automation capabilities of XML.

1) Export your Sequence as an OMF composition. This will convert all audio sources into the OMF
2) Export your Sequence as an XML file. Run this through XMLPro to create a Pro Tools Session.

For the next stages, it is often best to have the audio source files Offline, in order to avoid side effects where Pro Tools may reject audio regions because they are connected to incompatible files

3) In Pro Tools open the OMF, and create a Pro Tools session, which contains all the audio, but has no volume automation. Save this.
4) Next, Open the Pro Tools session created by XMLPro. This session will have dummy regions, relating to the FCP clips, and will have all the Volume automation in place.
5) In Pro Tools, select 'Import Session Data' and 'merge' in the Pro Tools session created from the OMF file, onto new audio tracks. This should give you a session with 2 sets of tracks - one with good media, but no automation, and one with dummy regions, but with good automation.
6) The trick now is to remove all the dummy regions, and select all the good audio on the other tracks, and slide them into place on top of the volume automation. You need to be careful when removing the dummy regions, since in some edit modes, Pro Tools will remove the automation when you delete the regions. It is best to remove the audio regions from the region bin, rather than from the tracks themselves. The best option is to select all in the region bin and remove ALL the regions BEFORE you perform step 5) to import the OMF audio regions.

Having moved the good audio regions into place on top of the good volume automation, you should have the material you need to proceed.

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