How can I filter media by author

Hi

I set up wordpress 2.9.2 in such a fashion that any subscriber has “contributor” role and can add media to the site.

What I want to do is for each contributor to only display the media uploaded by that contributor. In other words, in the backend if the contributor is logged in and clicks on Media I want to “filter” the results by author where author is the logged in user. At the same time i want the administrator role to be able to see all media so as to be able to delete explicit content.

I have some php experience but have no idea where the sources are to start looking to build this “filter”.

An Idea:
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I am using the role-manager plugin as from:
https://www.im-web-gefunden.de/wordpress-plugins/role-manager/
On this site the author explains how the dashboard button can be hidden by adding a capability to a role – would a similar approach be the way to go? – adding a capability to view all media/only view own media

Thanks in advance