The disclosure details methods and systems for watermark encoding and decoding in imaging devices, such as printers and scanners, and imaging device interfaces. Watermark encoding and decoding functions are incorporated into printer and scanner image processing pipelines. Watermark encoders and decoders perform watermark encoding and decoding, respectively, on an image as it is being transferred from one stage of a printing or scanning process to another. In particular, streaming mode watermark encoders and decoders operate on sequential portions of the image in a sequential image stream passing from one stage to another. The streaming mode encoder and decoder may be incorporated in a printer or scanner driver in a computer connected to a printer or scanner peripheral or within a printer or scanner device.