When an action is started from the UI, not the batch processor, it is possible to manipulate a selected artwork item. This is only possible if the following conditions are met:
You can test if the conditions are satisfied via the \sa escape sequence. The sequence is unescaped as:
The trailing @ is required for internal processing.
The \sa sequence can be inserted from a context menu's Insert Escape Sequence > Miscellaneous > Selected Artwork Indicator menu item.
The following artwork action statements support the \sa sequence in their appropriate index field.
Artwork to Folder
Crop Artwork*
Duplicate Artwork
Indexed Artwork*
Manipulate Artwork*
Rearrange Artwork
When the index is specified as \sa, the selected artwork item will be used for files which contain the item.
The \sa sequence allows you to create an action which operates on a single artwork item selected in the UI where an appropriate index is supplied for each selected file.
While the \sa sequence can be used to determine if the required conditions are met and it can be specified as an index, it does not guarantee that a particular file has the selected artwork item. All of the statements above handle this case.
The Indexed Artwork statement has a Resolve Selected UI Index function which resolves the index of the currently selected artwork item, if any, based on the conditions. -1 implies invalid. Note that this is only required if you need the resolution information on a per file basis for a specific reason. The above statements do the validation automatically.
Note that the determination of an item matching the selected artwork item operates by matching metadata and artwork data. Those statements listed above which are followed by an *, can cause the originally selected artwork item to no longer exist. If this is the case subsequent uses of \sa will no longer match the item in subsequent statements