OMF File - What is an OMF File? How To Use An OMF File..
What is a OMF file?
A OMF file or OMFI file stands for Open Media Framework / Open Media Framework Interchange.
The OMF file is typically used to exchange data with audio software such as Pro Tools. The OMF file supports the exchange of audio data only, MIDI and any automation is ignored.
The main advantage is being able export hundreds of audio files in one file (when self-contained) allowing you to see where all individual files are and any edits done prior to sound editing, such as cross fades, levels and panning.
Here below are the ways to export a OMF file from various video editing software applications.
*NOTE: If you don't export a self contained OMF then you need to also send all the referenced information as well so the OMF can find it all. You can tell if the OMF is self-contained because the file will be fairly large (number of files depending)
*NOTE: OMF files limit at 2GB so you may need to do several exports.
If you want more video or sound editors to be added and explained just leave a comment below.
Exporting an OMF file in Logic 9
There are various options for a OMF file, here is a break down.
OMF file Version - There are 2 versions of the OMF file format. I always recommend using version 2 unless you are trying to make it compatible with very old software like pro tools 7.
Include Audio - If active this integrates all exported audio files into the OMF file itself. This makes the OMF file very large depending on the length of the project you are exporting. If NOT active you will need to save the OMF and all the reference files used in the project to be copied to any new hard disk you are wanting to send off to someone else. same for sending files online.
Convert interleaved to split stereo - Some applications don't support interleaved stereo files. For these older applications select this option and it will give you 2 mono files for each stereo track as an L and R track. This will only work if the "Include Audio" option is selected.
Convert 24 bit files to 16 bit - This is an option for older software again. I would recommend not checking this option
Dither Type: Choose None or any of the four dither algorithms.
Exporting FCP 7 Audio to a OMF File
- Choose a sequence to export by having it selected in the Timeline function.
- In the Timeline, you will need any tracks you want to include in your OMF enabled via the green speaker icon on the very left of each track. When highlighted green the track will be exported.
- Choose File > Export > Audio to OMF.
- In the OMF Audio Export dialog, choose the options you want, then click OK.
- Sample Rate: You want this to be the most commonly used sample rates of the files used. For instance if you recorded on set dialogue at 48kHz and some of your effects are at 44.1kHz then I would choose 48kHz as that would be the most common format.
- Bit Depth: 16 bit is more compatible with older types of software that import OMF files and keeps down the file size. 24 Bit is more information which is usually better.
- Handle Length: Sometime the sound editor will need to use a bit more of a clip to create a fade or smooth dialogue. Handles give the sound editor the ability to drag the defined clip IN/OUT points by the number of handle length seconds. I recommend 3-10 seconds. Speak to your sound editor first about this. If you choose 5 seconds but the file only has 3 seconds outside the IN/OUT point then FCP will export the maximum of 3 seconds.
- Include Crossfade Transitions: Crossfades will be redone by your sound editor but you can include any to show what works for you so far. Unless important I wouldn't include this.
- Include Levels: Again your sound editor will level everything again and so only include levels if you want a reference for them as they will copy the OMF and make their own adjustments.
- Include Pan: Your sound editor will also pan as needed so not really important to include unless there is a specific reference needed.
- Choose a location and enter a name for the file.
- When you’re ready to export, click Save.
Export a OMF file for Pro Tools in Premiere Pro CC / CS6
1 - In a Timeline panel, select a sequence.
2 - Select File > Export > OMF.
From the OMF export Dialog Box:
- Type title for what your OMF file will be called
- Sample Rate and Bit Depth is usually 48kHz and 24 Bit for high quality audio. Match these to your sequence settings or generally the most used type of files. On set recordings will make up the most part of the audio files in any sequence so do the same as them if in doubt.
From the Files menu choose either:
Encapsulate - With this setting, Premiere Pro exports a OMF file containing the project metadata and all the audio for the selected sequence. Encapsulated OMF files typically are large. These have a 2GB limit and are the easiest way to keep everything together.
Separate Audio - With this setting, Premiere Pro exports individual mono AIF files into a _omfiMediaFiles folder. The folder name contains the OMF filename you chose at the top. Using AIF files assures maximum compatibility with legacy audio systems. This can be a better option if you don't want to send multiple encapsulated OMF files.
From the Render menu, choose one of the following:
Copy Complete Audio Files - With this setting, Premiere Pro exports audio for the entirety of each clip used in the sequence, no matter how many times the clip is used nor how many parts of the clip are used. This will make your files very large but could be good if you have all the rushes imported for relevant shots and want to essentially have an unlimited handle length for the sound editor.
Trim Audio Files - With this setting, Premiere Pro exports only the portions of each clip that are used in the sequence: the clip instances. You can choose to export each clip instance with extra length, handles, added to the start and end of the file. This is the most common setting with handles being between 3-10 seconds.
In the Handle Frames field, specify the length of the handles, in video frames. This amount of time is added to the start and end of the exported files when you choose Consolidate Media. The default setting is one second, in frames, at the sequence frame rate. If the length of the handles you specify exceeds the length of the clip instance, Premiere Pro exports the whole clip instance.
Then you should export it :)