What is the action hook for save media-form on gallery tab?

Question

I want to save a meta data to post parent when the media-form on gallery tab is saved( The submission button is "Save All Changes"). Which action hook can I use?

Answer 1

For updates it is 'edit_attachment' and for new attachments 'add_attachment'.

There is no action dedicated to images coming from the gallery tab, but you could check the global array $_FILES. If there is a $_FILES['async-upload'] it is probably a request from the media popup.