postgresql : find privileges in meta informations
I find it by myself !

Tables to be parsed to have all metadata on ACL and privileges given by ALTER DEFAULT PRIVILEGES can be found in pg_catalog.pg_default_acl and pg_catalog.pg_namespace with the help of pg_catalog.pg_authid.

Some references :


http://www.postgresql.org/docs/9.4/static/catalog-pg-default-acl.html
http://www.postgresql.org/docs/9.4/static/catalog-pg-namespace.html