Iterative gamut mapping

A method for mapping an input point to a surface of a color gamut in a color space, comprising:

• a selecting step to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• a first determining step to determine a projection point in the two-dimensional slice;
• a second determining step to determine a projection between the input point and the projection point;
• a third determining step to determine an intersection point between the projection and a mathematical approximation of the surface of the color gamut;
• a fourth determining step to determine a new mathematical approximation between points at least substantially on the surface of the color gamut, wherein the new mathematical approximation is determined based on the intersection point;
• a redetermining step to redetermine the intersection point, wherein the intersection point is redetermined at an intersection between the projection and the new mathematical approximation;
• and
• a repeating step to repeat the fourth determining step and the redetermining step until the intersection point satisfies a goodness criteria.

An apparatus for mapping an input point to a surface of a color gamut in a color space, comprising:

• a memory including a region for storing executable process steps;
• and
• a processor for executing the executable process steps;
• wherein the executable process steps include the steps of:
• (a) selecting a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• (b) determining a projection for mapping the input point to the surface of the color gamut;
• and (c) repeatedly estimating a point where the projection intersects the surface of the color gamut by repeatedly performing the steps of determining an approximation of the surface of the color gamut, and determining an intersection of the projection with the approximation, wherein after each estimation, the approximation is updated based on the intersection.

An apparatus for mapping an input point to a surface of a color gamut in a color space, comprising:

• a memory for storing executable process steps;
• and
• a processor for executing the executable process steps;
• wherein the executable process steps include:
• (a) a selecting step to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• (b) a first determining step to determine a projection point in the two-dimensional slice;
• (c) a second determining step to determine a projection between the input point and the projection point;
• (d) a third determining step to determine an intersection point between the projection and a mathematical approximation of the surface of the color gamut;
• (e) a fourth determining step to determine a new mathematical approximation between points at least substantially on the surface of the color gamut, wherein the new mathematical approximation is determined based on the intersection point;
• (f) a redetermining step to redetermine the intersection point, wherein the intersection point is redetermined at an intersection between the projection and the new mathematical approximation;
• and (g) a repeating step to repeat the fourth determining step and the redetermining step until the intersection point satisfies a goodness criteria.

Computer-executable process steps stored on a computer-readable medium, the computer executable process steps for mapping an input point to a surface of a color gamut in a color space, the computer-executable process steps comprising:

• code to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• code to determine a projection for mapping the input point to the surface of the color gamut;
• and
• code to estimate repeatedly a point where the projection intersects the surface of the color gamut by repeatedly performing the steps of determining an approximation of the surface of the color gamut, and determining an intersection of the projection with the approximation, wherein after each estimation, the approximation is updated based on the intersection.

Computer-executable process steps for mapping an input point to a surface of a color gamut in a color space, comprising:

• selecting code to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• first determining code to determine a projection point in the two-dimensional slice;
• second determining code to determine a projection between the input point and the projection point;
• third determining code to determine an intersection point between the projection and a mathematical approximation of the surface of the color gamut;
• fourth determining code to determine a new mathematical approximation between points at least substantially on the surface of the color gamut, wherein the new mathematical approximation is determined based on the intersection point;
• redetermining code to redetermine the intersection point, wherein the intersection point is redetermined at an intersection between the projection and the new mathematical approximation;
• and
• repeating code to repeat execution of the fourth determining code and the redetermining code until the intersection point satisfies a goodness criteria.

A computer-readable medium which stores computer-executable process steps, the computer-executable process steps for mapping an input point to a surface of a color gamut in a color space, the computer-executable process steps comprising:

• a selecting step to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• a determining step to determine a projection for mapping the input point to the surface of the color gamut;
• and
• a repeated estimating step to estimate repeatedly a point where the projection intersects the surface of the color gamut by repeatedly performing the steps of determining an approximation of the surface of the color gamut, and determining an intersection of the projection with the approximation, wherein after each estimation, the approximation is updated based on the intersection.

A computer-readable medium which stores computer-executable process steps, the computer executable process steps for mapping an input point to a surface of a color gamut in a color space, the computer-executable process steps comprising:

• a selecting step to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• a first determining step to determine a projection point in the two-dimensional slice;
• a second determining step to determine a projection between the input point and the projection point;
• a third determining step to determine an intersection point between the projection and a mathematical approximation of the surface of the color gamut;
• a fourth determining step to determine a new mathematical approximation between points at least substantially on the surface of the color gamut, wherein the new mathematical approximation is determined based on the intersection point;
• a redetermining step to redetermine the intersection point, wherein the intersection point is redetermined at an intersection between the projection and the new mathematical approximation;
• and
• a repeating step to repeat the fourth determining step and the redetermining step until the intersection point satisfies a goodness criteria.

An apparatus for mapping an input point to a surface of a color gamut in a color space, comprising:

• selecting means to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• determining means to determine a projection for mapping the input point to the surface of the color gamut;
• and
• estimating means to estimate repeatedly a point where the projection intersects the surface of the color gamut by repeatedly performing the steps of determining an approximation of the surface of the color gamut, and determining an intersection of the projection with the approximation, wherein after each estimation, the approximation is updated based on the intersection.

An apparatus for mapping an input point to a surface of a color gamut in a color space, comprising:

• selecting means to select a two-dimensional slice of the color space, the two-dimensional slice including the input point;
• first determining means to determine a projection point in the two-dimensional slice;
• second determining means to determine a projection between the input point and the projection point;
• third determining means to determine an intersection point between the projection and a mathematical approximation of the surface of the color gamut;
• fourth determining means to determine a new mathematical approximation between points at least substantially on the surface of the color gamut, wherein the new mathematical approximation is determined based on the intersection point;
• redetermining means to redetermine the intersection point, wherein the intersection point is redetermined at an intersection between the projection and the new mathematical approximation;
• and
• repeating means to cause the fourth determining means and the redetermining means to repeat their respective operations until the intersection point satisfies a goodness criteria.