printed image a steganographic calibration signal may be used to help register or align the image for accurate steganographic encoding detection an exemplary embodiment of the present invention includes a cell phone faceplate fig5 the faceplate includes a steganographically encoded image not shown in fig5 the steganographic encoding includes a message or payload the message or payload provides a tool for authenticating the faceplate for example the presence of the message or payload may itself signal that the faceplate is authentic or the condition of the encoding may indicate that it is a copy aka a fragile digital watermark still further a message or payload may include a link to a network resource which provides information to help authenticate the faceplate in other implementations the message or payload includes information that can be cross correlated with information carried elsewhere on the faceplate or cell phone for example the payload or message may include information for comparison against a serial number or frequency code printed or engraved on the faceplate or cell phone and of course other steganographic encoding techniques discussed above including a calibration signal can be employed with the cell phone faceplate of fig5 in other implementations the encoding includes two or more digital watermarks in preferred implementations of this embodiment the fig5 cell phone faceplate is manufactured according to the fig1 process an inspector.