Color gamut size metric estimation
AssigneeApple Inc.
InventorsYingjun Bai, Xuemei Zhang
Life of this patent
Estimating the term…
Abstract
A gamut size metric is used in all phases of color image processing (e.g., capture, transmission, and display). In general, the gamut size metric is a single-valued metric that changes as image content changes. More particularly, a gamut boundary histogram is determined and used to estimate a gamut size metric. A gamut size metric identifies a minimum size gamut needed to encompass each pixel in an image, where the gamut size is limited at one end by a first device independent gamut (S1), and at another end by a second device independent color space (S2), where S1 is wholly enclosed within S2. The gamut size metric may be based on strict pixel color value differences. In other embodiments the gamut size metric may take into effect perceptual color differences and significance.
Claims21
A method for gamut size estimation in image processing, comprising:
- obtaining a color image;
- processing, by a computer processor, each of a plurality of pixels of the color image by—
- determining a gamut boundary value for a pixel, wherein the gamut boundary value identifies a smallest size gamut that encapsulates the pixel, and
- updating a bin of a gamut boundary histogram that corresponds to the gamut boundary value;
- and
- determining, by the computer processor, a gamut size metric based on the gamut boundary histogram, wherein the gamut size metric is indicative of a minimum gamut needed to represent the color image.
A non-transitory program storage device comprising instructions stored thereon to cause one or more processors to:
- obtain a color image;
- process each of a plurality of pixels of the color image by—
- determining a gamut boundary value for a pixel, wherein the gamut boundary value identifies a smallest size gamut that encapsulates the pixel, and
- updating a bin of a gamut boundary histogram that corresponds to the gamut boundary value;
- and
- determine a gamut size metric based on the gamut boundary histogram, wherein the gamut size metric is indicative of a minimum gamut needed to represent the color image.
An electronic device, comprising:
- a memory;
- and
- one or more processors operatively coupled to the memory and configured to execute instructions stored in the memory to cause the electronic device to—
- obtain a color image from the memory;
- process each of a plurality of pixels of the color image by—
- determining a gamut boundary value for a pixel, wherein the gamut boundary value identifies a smallest size gamut that encapsulates the pixel, and
- updating a bin of a gamut boundary histogram that corresponds to the gamut boundary value;
- and
- determine a gamut size metric based on the gamut boundary histogram, wherein the gamut size metric is indicative of a minimum gamut needed to represent the color image.
Dependencies are inferred from the claim text.