As a source media you must specify an URL that could be of three types:
1) http://[user]:[password]@[server]/[path]/[filename] or
2) ftp://[user]:[password]@[server]/[path]/[filename] or
3) http://[your_bucket].s3.amazonaws.com/[path]/[filename]
You can omit [user]:[password]@ in case of public (not password protected) resources. In last case, the bucket must have READ permission for AWS user 1a85ad8fea02b4d948b962948f69972a72da6bed800a7e9ca7d0b43dc61d5869.
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