Prevent other editors from viewing images of other editors in Add Media Popup

If I correctly understand your question, you may try this

function wpse78084_show_media_by_current_author_only($query) {
  global $pagenow, $user_ID;

  if( 'upload.php' == $pagenow && !current_user_can('manage_options') )
    $query->set('author', $user_ID);

return $query;
}

if ( is_admin() )
  add_filter('pre_get_posts', 'wpse78084_show_media_by_current_author_only');