Image encoding requirements

ResolutionNewsprint: between 120 and 750dpi
Commercial: between 150 and 750dpi
ColorspaceCMYK preferred, RGB, Grayscale supported*
Bit Depth8 Bits per Channel
File FormatJPEG, TIFF**
SizeThe recommended artwork size is 2" x 2" or larger for optimal watermarking and readability. Digitally watermarking artwork smaller than 2" x 2" is possible, but may require using higher strength settings and a limited range of colors to provide readability for most smartphones. Watermarking artwork as small as 0.5" x 0.5" is allowed, though not recommended due to limited readability by only the best mobile camera devices.
Ink DensityA maximum of 300%
As CMYK ink coverage increases — especially above 300% — most printers have trouble reproducing the details of the digital watermark accurately.
* Watermarking RGB images can produce unexpected results when printed.
** TIFF and LZW compressed TIFF supported. Layered TIFFs are not supported