Encoding volumetric data to support trusted transaction delivery

A computer-implemented method to facilitate creation of a three-dimensional item by an additive manufacturing process, comprising:

• receiving an item definition file containing a volumetric description of the three-dimensional item, wherein the item definition file includes a plurality of item slices, from a bottom item slice to a top item slice, each item slice describing a two-dimensional portion of the three-dimensional item;
• identifying a particular item slice as an anchor item slice when differences between the particular item slice and another item slice exceed a pre-determined or adaptable threshold;
• for at least some of the item slices, encoding data in the item definition file describing an additional item slice in terms of differences between the additional item slice and the anchor item slice below the additional item slice to create a compressed item definition file including a compressed volumetric description of the three-dimensional item;
• and
• transmitting the compressed item definition file to an additive manufacturing printer.

A system to facilitate creation of a three-dimensional item by an additive manufacturing process, comprising:

• an input port configured to receive a compressed item definition file containing a compressed volumetric description of the three-dimensional item, wherein the item definition file includes a plurality of item slices, from a bottom item slice to a top item slice, each item slice describing a two-dimensional portion of the three-dimensional item;
• and
• a computer processor coupled to the input port and adapted to:
• for at least some of the item slices, decode data in the compressed item definition file as a description of a particular item slice in terms of differences between the particular item slice and an anchor item slice below the particular item slice, wherein the anchor item slice is indicative of an item slice of the plurality of item slices in which differences between the anchor item slice and another item slice exceed a pre-determined or adaptable threshold;
• create an item definition file including a non-compressed volumetric description of the three-dimensional item;
• and
• output the item definition file for use by an additive manufacturing process printer.