// Ticket item indicating what image resolution to use. message DpiTicketItem {

// Horizontal DPI to print at (required).
optional int32 horizontal_dpi = 1;

// Vertical DPI to print at (required).
optional int32 vertical_dpi = 2;

// Vendor-provided ID of the Dpi option. Needed to disambiguate Dpi options
// that have the same DPI values, but may have a different effect for the
// printer.
optional string vendor_id = 3;

}