The objective of this research is to propose a data hiding method for printed images. Three digital halftoning techniques
Floyd-Steinberg error diffusion (FSED), multi-scale error diffusion (MSED) and modified multi-scale error diffusion (MMSED)
are implemented in the view of binarization sequence. Microscopic pictures on printed halftone images at different resolutions
are presented for visual inspection. A print-and-scanned image with 16 sub-regions of varied dot percentage is used to evaluate
the quality of data recovery. The results show that data recovery has better performance at the low dot percentage region
and MMSED can provide greater feasibility for data hiding in printed binary images. The proposed method has numerous potential
applications in security printing.