Updating a lookup table for an imaging system

An imaging system comprising:

• an imaging device to produce an image output;
• a memory storing:
• an initial color lookup table comprising nodes to map from a vertex-to-vertex axis of a first color space to vectors in a second color space;
• and
• a smoothed color lookup table comprising nodes to map from the vertex-to-vertex axis of the first color space to vectors in the second color space, the smoothed color lookup table being a smoothed version of the initial color lookup table;
• and
• color property values representative of measurements of respective test areas rendered by the imaging device that are associated with nodes from the lookup tables;
• an imaging controller to:
• compare color property values associated with nodes from the smoothed color lookup table with color property values associated with nodes from the initial color lookup table;
• and
• for a given node in the smoothed color lookup table:
• select, based on the compared color property values, a subset of nodes from the initial color lookup table;
• and
• update a vector corresponding to the given node based on an interpolation of vectors corresponding to the subset of nodes, the updated vector being constrained based on a color property value for the given node.

A non-transitory computer-readable storage medium comprising a set of computer-readable instructions that, when executed by a processor of an imaging system, cause the processor to:

• receive an initial lookup table comprising an initial set of nodes that map input vectors on a vertex-to-vertex axis of a first color space to initial output vectors in a second color space;
• receive a smoothed lookup table comprising a target set of nodes that map input vectors on the vertex-to-vertex axis to respective target output vectors in the second color space, the smoothed lookup table being a smoothed version of the initial lookup table;
• receive color property values associated with the initial and target set of nodes, the color property values being derived from color property measurements of test areas rendered by the imaging system;
• select, for a given node in the target set of nodes, two nodes in the initial set of nodes based on the received color property values;
• and
• update a target output vector for the given node based on an interpolation of the initial output vectors corresponding to the selected two nodes, the target output vector being constrained based on a received color property value for the given node.