CatDV’s ethos is non-destructive metadata management, i.e. metadata is stored in the CatDV database so there is no possibility that CatDV could damage source footage.

At the same time there may be times when it is necessary to write CatDV metadata back to the original files. This tutorial describes how to do this using a third party, open source tool: exiftool.

Please note that there are risks involved with changing the original media files. It is your responsibility to ensure you have adequate confidence in this kind of workflow and/or suitable backups in case of media corruption.


This tutorial uses the CatDV worker to control exiftool, an excellent piece of software available at: for Mac and Windows.

This tutorial is based on Mac OSX using CatDV Worker 5.0.7 and the exiftool 9.5. The approach on Windows is the same and this tutorial covers both platforms


In this tutorial we shall set up CatDV to be able to update EXIF, XMP and ICMP metadata, then use a server query in the CatDV Worker to trigger exiftool to write the metadata back to the file.

1. Install exiftool

Follow the instructions at  to install exiftool. To test the installation, type ‘exiftool’ into a terminal window / command prompt and some help pages should appear showing that the installation was successful and exiftool is accessible.

Advice to windows users would be to put the renamed exiftool in a folder within the program files directory eg “C:\Program Files (x86)\exiftool\exiftool.exe”

2. Setup CatDV to edit exif metadata

In CatDV Preferences choose Field Definitions, then press the Metadata Columns button. Ensure the “Enable Metadata columns” and “Allow editing of ‘read-only’ metadata” are both checked:


Then set up a CatDV Details Panel to show the required metadata columns (including xmp:CreatorTool for this tutorial). See here for instructions on creating a Details Panel.

3. Set up a field to trigger the worker action

In the CatDV Preferences choose Field Definitions and add a user-defined field that will trigger the worker action. In this case called “Write Metadata To File” as a radio button with the only value available ‘yes’:


4. Set up a Worker action to write the metadata

Set up a worker action: as a server query triggered by the Write Metadata To File field being ‘yes’. Ensure the workflow only runs on online files (ie the media is accessible at the time) that ‘allow polling’ is set (so that the same workflow can run multiple times for the same asset) and that ‘allow sequences and metaclips’ is not set.

  • Then use the exiftool command line to write the metadata to the file. In this example we will write the CatDV notes field ${NT} to the album notes field (xmp:Notes), we shall also update some built in metadata for xmp:CreatorTool. The command required in the worker is:

exiftool -xmp:Notes=${NT} -xmp:CreatorTool=${@xmp:CreatorTool} $b

or for windows users

“C:\Program Files (x86)\exiftool\exiftool.exe” -xmp:Notes=${NT} -xmp:CreatorTool=${@xmp:CreatorTool} $b

This sets the metadata fields in the file to CatDV metadata:

  • ${NT} is the CatDV notes field
  • ${@xmp:CreatorTool} is CatDV’s (editable) version of the file’s Creator Tool field
  • $b is the original file path of the asset

Your workflow will no doubt want to update different metadata fields. Press the help button in the worker or see the worker documentation for more information about the fields and data available to worker commands. Note that for exif, xmp style metadata (ie fields that originated outside CatDV) an @ can be used to reference the fields per the example above.

Note that mis-setting some of this metadata (for example the codec or compression type) may corrupt the media so care should be taken here. The exiftool by default creates a backup of the original media when it updates a file. However if metadata is written multiple times, old backups will be overwritten so this should not be relied upon. More sophisticated workflows that copy the original file etc could be created to mitigate risk.

Finally on the Publish tab, don’t forget to update the Write Metadata To File field to something other than ‘yes’ to indicate that the clip has now been processed (and the workflow can be run again if necessary). As below:

Write metadata eg





 5. Test the action

In CatDV set the Write Metadata To File field to say ‘yes’ for an asset and publish changes to the CatDV Server (ctrl/cmd-s). This will trigger the Worker job which will complete. To check that metadata has been written correctly: in CatDV either reimport the source media or use the Tools – Reanalyse Media command which will update the exif, xmp etc data from the information stored in the file.