The ‘Trigger’ tab defines whether files are processed because they appear in a watch folder or when they are drag and dropped. The ‘Conditions’ tab defines various filter conditions that the file must match for this watch action to be performed. Finally, the ‘Job Details’ and ‘Post-Processing’ To use watch folders the root watch folder must be specified. You can choose whether to only analyse files that appear in the watch folder or recursively in any subdirectory.
Alternatively, you can also enable drag and dropping of files directly onto the worker node application window. You must enable either the watch folder or dropping files (or both) or the watch action won’t be active (though there may be situations where it’s useful to disable a watch folder so it isn’t scanned without having to delete the entire watch action definition).
To avoid processing a file while it is still being captured or copied a settle period can be defined. Files are ignored if they are less than a given number of seconds old. The check interval defines how often the watch folder is scanned. Increase this period if you are recursively large directories on a slow external volume. (These fields can be left blank to use their default values).
If you want to limit the processing to files of a particular type you can do so by setting various filter conditions.
The simplest and most efficient test is to only include files whose name matches a particular pattern, or which does not match the ‘exclude’ pattern. The filters can either be simple patterns, such as ‘*.mov’ or a complex regular expression such as ‘/[A-Za-z]+.mp4$’ if the regex box is checked. Case is normally ignored when matching these patterns.
Other tests involve analysing the file by trying to open it as a media file (using QuickTime). You can choose one of various basic types (eg. QuickTime movie, AVI movie, MPEG movie, Still image, Non media file) from the drop down, or for media files add additional criteria based on the movie duration in seconds, the audio and video format, or testing for arbitrary track types.
In each case, you can check for the presence or absence of a particular property, and if you leave a field blank the condition will not be checked.
For video and audio tracks a description of the format (like the Video and Audio fields of CatDV) is checked for the presence of the text you type in. For example, Video might say “Photo – JPEG (480×320 30.0fps)” while the Audio description might be “MPEG Layer-3 Audio (44.1 kHz, stereo, 16 bit). Any substring will match, so you could type “JPEG” or “30.0fps” or “Photo – JPEG (480×320” in a condition.
To test for the presence of arbitrary track types, enter the type and subtype codes as displayed in the QT Tracks field of CatDV.