Method and system for amplitude modulated screening and protecting printouts, computer program, printing device and printed product

A printing press, comprising:

• a device for computer-implemented generation of an amplitude modulated multi-cluster halftone dot for use in an amplitude modulated screen, said device being configured for:
• determining an arrangement of clusters within the dot, determining a cluster function for each cluster, the cluster function defining a pixel sequence indicating a sequence of turning on device pixels within an area of a particular cluster;
• providing at least two clusters within the dot having different shapes and different numbers of the device pixels;
• determining a dot function for the dot, the dot function defining a cluster sequence;
• indicating a sequence of the clusters;
• and
• generating a set of data representative of the dot for a particular tonal value, by determining the device pixels within the dot turned on for that particular tonal value according to the cluster functions and the dot function.