ORA-19599: block number <varname>string</varname> is corrupt in <varname>string</varname> <varname>string</varname>
Cause: A corrupt block was found in a control file, archived log, or backup piece that is being read for a backup or copy. Corruption shall not be tolerated in control files, archived logs, or backup pieces.
Action: None. The copy or backup operation fails. Note that in the case of a backup set, the conversation is still active and the piece may be retried.
So if you are trying to restore a production database, then I'd say you need to raise an Oracle SR to get Oracle advice on what to do.
The only backup pieces are compressed
I suggest checking whether the I/O error is because of bad hardware or a bad connection. If the backup files are indeed corrupt, then the backup is useless. You may have alternative options to restore the database, but unless you provide more information....