Method and apparatus for anisotropically modifying text attributes to comply with a resolution limit

A method for proofing at least a selected part of a graphical data input file for output to an output device, the method comprising automatically adjusting, using a computer programmed to perform such adjusting, at least one graphics feature in the input file to compensate for a predetermined resolution limit, the method comprising the steps of:

• (a) automatically identifying, using the computer, in the selected part of the input file, one or more portions having an initial thickness less than the predetermined resolution limit;
• (b) automatically determining a set of optimal anisotropic path offset parameters that when applied will bring the one or more portions above the predetermined resolution limit with a minimal total offset value;
• (c) automatically modifying with the computer the selected part of the input file so that the identified one or more portions have an adjusted thickness greater than the initial thickness, said modifying comprising applying an offset using the identified set of optimal anisotropic path offset parameters;
• (d) creating, using the computer, ab output file comprising the at least one graphics feature having the adjusted thickness;
• and
• wherein the step of automatically determining a set of optimal anisotropic offset parameters comprises analyzing the results of a skeletonization operation, the step of analyzing the results of the skeletonization operation comprising:
• (i) building a 2 dimensional histogram representing stroke direction divided into 180/n direction intervals of n degrees each, and k weight intervals equally divided in a range between 0 and the predetermined resolution limit, with a value of each cell in the interval comprising a total stroke length for the identified part of the file having the stroke direction and weight defined by the cell, and
• (ii) iteratively testing a plurality of offset conditions until a total stroke length represented by a sum of all cells in the histogram is less than or equal to a predetermined percentage of a total stroke length of all strokes in the identified part.

A system for proofing at least a selected part of a graphical data input file for output to an output device, the system configured for automatically adjusting at least one graphics feature to compensate for a predetermined resolution limit, the system comprising a controller comprising a processor having a memory programmed with instructions for performing the method steps of:

• (a) automatically identifying, using the controller, one or more portions of the selected part of the input file that have an initial thickness less than the predetermined resolution limit;
• (b) automatically determining a set of optimal anisotropic path offset parameters that when applied will bring at least a selected percentage of the one or more portions above the predetermined resolution limit with a minimal total offset value;
• (c) automatically modifying with the controller the selected part of the input file so that the identified one or more portions have an adjusted thickness greater than the initial thickness, said modifying comprising applying an offset using the identified set of anisotropic path offset parameters;
• (d) creating, using the controller, an output file comprising the at least one graphics feature having the adjusted thickness;
• wherein the step of applying an offset using the identified set of optimal anisotropic path offset parameters can be expressed as applying one or more ellipses to the selected part of the input file, each of the one or more ellipses having an offset distance (D) in a major diameter direction, another offset distance (d) in a minor diameter direction that is perpendicular to the major diameter direction, and an angle (a) of the major diameter direction relative to a lateral direction, wherein D>d.

A non-transitory computer readable media including program instructions for proofing at least a selected part of a graphical data input file for output to an output device, the instructions programmed for automatically adjusting at least one graphics feature in the input file to compensate for a predetermined resolution limit, said program instructions when executed by a processor for causing the processor to perform the steps of:

• (a) automatically identifying, using the processor, one or more portions of the selected part of the input file having an initial thickness less than the predetermined resolution limit;
• (b) automatically determining a set of optimal anisotropic path offset parameters that when applied will bring at least a selected percentage of the one or more portions above the predetermined resolution limit with a minimal total offset value;
• (c) automatically modifying with the processor the selected part of the input file so that the identified one or more portions have an adjusted thickness greater than the initial thickness, said modifying comprising applying an offset using the identified set of anisotropic path offset parameters;
• (d) creating, using the processor, an output file comprising the at least one graphics feature having the adjusted thickness;
• and
• wherein the step of applying an offset using the identified set of optimal anisotropic path offset parameters can be expressed as applying one or more ellipses to the selected part of the input file, each of the one or more ellipses having an offset distance (D) in a major diameter direction, another offset distance (d) in a minor diameter direction that is perpendicular to the major diameter, and an angle (a) of the major diameter direction relative to a lateral direction, wherein D>d.