Mapping for custom fields

Problem/Motivation

In our project, there are custom fields in kontainer, such as a copyright notice. We would like to transfer the values of certain custom fields to Drupal so that we don't have to maintain them twice.

Steps to reproduce

Proposed resolution

The custom fields are already included in the response of an image query and could be processed:

[cf] => Array
  (
    [Copyright] => Copyright notice
)

I could imagine that there is a UI where you can configure how the custom fields should be mapped to Drupal fields.

Would the proposed solution be feasible or is there an alternative solution?