imagescale mit ordsys.ordimage

declare
    vID     blob;
    vSI     blob;
begin
    select  blob_file
      into  vID
      from  img_files
      where file_id = 1234; 

    dbms_lob.createtemporary(vSI, false, dbms_lob.call);
    ordsys.ordimage.processcopy(vID, 'maxscale=75 75', vSI);

    update  img_files 
      set   blob_file    = vSI 
      where file_id     = 1234; 
end;