I have created a Custom Field and have it working successfully but I wanted to know is there a hook where i can customise the output of the value returned from the database? on the post edit screen and shortcode pages?
e.g. currently the value for my custom field returns 'example.jpg'
and I want to run a custom JS function to perform a action on this value when a user is viewing the edit post form.
I need to do this as my custom field expects the existing value to be in a certain format in order for it to be edited.