Color separation multiplexing for real-time multi-dimensional device calibration

• US 7,956,867 B2
• Filed: 05/09/2008
• Issued: 06/07/2011
• Est. Priority Date: 05/09/2008
• Status: Expired due to Fees

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Bala, Raja, Monga, Vishal
• Primary Examiner(s): Sajous; Wesner
• Application Number:
  US12/118,306
• Publication Number:
  US 20090279111A1
• Time in Patent Office: 1,124 Days
• Field of Search: 345418-419, 345/581, 345589-593, 345/586, 345/643, 345600-606, 345/549, 345/565, 345/690, 345/567, 348253-254, 348/557, 348/671, 358/1.1, 358/1.9, 358/504, 358/515, 358518-519, 358/523, 358/525, 382162-166, 382/254, 382/274, 382/232, 382/248, 382/276, 382/300
• US Class Current: 345/589
• CPC Class Codes: G06F 3/13 Digital output to plotter ; Cooperation and interconnection of the plotter with other functional units
• CPC Class Codes: G09G 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 2340/02 Handling of images in compressed format, e.g. JPEG, MPEG
• CPC Class Codes: G09G 5/00 Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators image data processing or generation, in general G06T
• CPC Class Codes: G09G 5/003 Details of a display terminal, the details relating to the control arrangement of the display terminal and to the interfaces thereto specific for a CRT G09G1/165; for a flat panel G09G3/2092
• CPC Class Codes: G09G 5/06 using colour palettes, e.g. look-up tables
• CPC Class Codes: H04N 1/603 controlled by characteristics of the picture signal generator or the picture reproducer
• CPC Class Codes: H04N 1/64 Systems for the transmission or the storage of the colour picture signal; Details therefor, e.g. coding or decoding means therefor H04N19/00 takes precedence

Abstract

In accordance with the disclosure, a method is provided for processing color images for rendering on a color image. The method comprises receiving a plurality of device color separations for an image intended for rendering on a color image device; forming at least one intermediate image by interleaving pixels from at least two of the device color separations, compressing the at least one intermediate image in a compression module; decompressing the at least one intermediate image in a decompression module; processing the at least one decompressed intermediate image through a multidimensional calibration transform to output a calibrated device color separation; and, the device color separations include at least three colors.

Claims

1. A method for processing a color image, comprising:

receiving a plurality of device color separations for an image intended for rendering on a color image device,

forming at least one intermediate image by interleaving pixels from at least two of the device color separations;

compressing the said at least one intermediate image in a compression module;

decompressing the said at least one intermediate image in a decompression module;

processing the said at least one decompressed intermediate image through a multidimensional calibration transform to output a calibrated device color separation; and

,

said device color separations include at least three colors.

2. The method of claim 1, wherein,

said device color separations include a first, second, and third color;

a first intermediate image is formed by interleaving said first color, treated as the primary component, with functions of said second and said third colors, treated as a first secondary component;

a second intermediate image is formed by interleaving said second color, treated as the primary component, with functions of said first and said third colors, treated as a second secondary component;

a third intermediate image is formed by interleaving said third color, treated as the primary component, with functions of said first and said second colors, treated as a third secondary component; and

,

said processing maps each intermediate image through said multidimensional calibration transform and outputs a calibrated separation corresponding to the primary component of each respective said intermediate image.

3. The method of claim 2, wherein,

for said first intermediate image, said first secondary component is formed as the sum of said second and third colors;

for said second intermediate image, said second secondary component is formed as the sum of said first and third colors; and

,

for the third intermediate image, said third secondary component is formed as the sum of said first and said second colors.

4. The method of claim 3, wherein,

said processing maps each intermediate image through a two-dimensional calibration transform and outputs a calibrated separation corresponding to said primary component of the associated said intermediate image, where the two dimensions of the calibration transform are respectively the primary and secondary components of the corresponding intermediate image.

5. The method of claim 4, wherein,

said first, second, and third secondary components of each said first, second, and third intermediate images is calculated at a reduced spatial resolution.

6. The method of claim 5, wherein,

said processing upsamples the secondary component of each intermediate image at full spatial resolution prior to mapping through the calibration transform.

7. The method of claim 6, wherein,

said upsampling involves interpolation among known pixel values to obtain missing pixel values.

8. The method of claim 7, wherein,

said secondary component of each said intermediate image is tonally quantized to a smaller number of bits.

9. A method for processing a color image for a color imaging device, comprising:

receiving a plurality of device color separations for an image intended for rendering on a color image device,

said device color separations include a first, second, and third color;

forming at least one intermediate image by interleaving pixels from at least two of the device color separations, wherein said at least one intermediate image is formed by interleaving said first color, treated as the primary component, with functions of said second and said third colors, treated as a first secondary component;

compressing the said at least one intermediate image in a compression module;

decompressing the said at least one intermediate image in a decompression module; and

,

processing the said at least one decompressed intermediate image through a multidimensional calibration transform to output a calibrated device color separation.

10. The method of claim 9, further comprising:

forming at least a second intermediate image by interleaving pixels from at least two of the device color separations, wherein said at least second intermediate image is formed by interleaving said second color, treated as the primary component, with functions of said first and said third colors, treated as a second secondary component;

compressing the said at least second intermediate image in a compression module;

decompressing the said at least second intermediate image in a decompression module; and

,

processing the said at least second decompressed intermediate image through a multidimensional calibration transform to output a calibrated device color separation.

11. The method of claim 10, further comprising:

forming at least a third intermediate image by interleaving pixels from at least two of the device color separations, wherein said at least third intermediate image is formed by interleaving said third color, treated as the primary component, with functions of said first and said second colors, treated as a third secondary component;

compressing the said at least third intermediate image in a compression module;

decompressing the said at least third intermediate image in a decompression module; and

,

processing the said at least third decompressed intermediate image through a multidimensional calibration transform to output a calibrated device color separation.

12. The method of claim 11 further comprising:

for said first intermediate image, said first secondary component is formed as the sum of said second and third colors;

for said second intermediate image, said second secondary component is formed as the sum of said first and third colors; and

,

for the third intermediate image, said third secondary component is formed as the sum of said first and said second colors.

13. The method of claim 12, wherein,

said processing maps each intermediate image through a two-dimensional calibration transform and outputs a calibrated separation corresponding to said primary component of the associated said intermediate image, where the two dimensions of the calibration transform are respectively the primary and secondary components of the corresponding intermediate image.

14. The method of claim 13, wherein,

said first, second, and third secondary components of each said first, second, and third intermediate images is calculated at a reduced spatial resolution.

15. The method of claim 14, wherein,

said processing upsamples the secondary component of each intermediate image at full spatial resolution prior to mapping through the calibration transform.

16. The method of claim 15, wherein,

said upsampling involves interpolation among known pixel values to obtain missing pixel values.

17. The method of claim 16, wherein,

said secondary component of each said intermediate image is tonally quantized to a smaller number of bits.

18. A method for processing a color image comprising:

receiving a plurality of device color separations for an image intended for rendering on a color image device,

forming at least one intermediate image by interleaving pixels from at least two of the device color separations;

compressing the said at least one intermediate image in a compression module;

decompressing the said at least one intermediate image in a decompression module;

processing the said at least one decompressed intermediate image through a multidimensional calibration transform to output a calibrated device color separation;

said device color separations include a first, second, and third color;

forming a first intermediate image by interleaving said first color, treated as the primary component, with a sum of said second and said third colors, treated as a first secondary component;

forming a second intermediate image by interleaving said second color, treated as the primary component, with a sum of said first and said third colors, treated as a second secondary component; and

,

forming a third intermediate image by interleaving said third color, treated as the primary component, with a sum of said first and said second colors, treated as a third secondary component.

19. The method of claim 18, wherein,

said processing maps each intermediate image through said multidimensional calibration transform and outputs a calibrated separation corresponding to the primary component of each respective said intermediate image.

20. The method of claim 19, wherein,

said first, second, and third secondary components of each said first, second, and third intermediate images is calculated at a reduced spatial resolution;

said processing upsamples the secondary component of each intermediate image at full spatial resolution prior to mapping through the calibration transform; and

,

said upsampling involves interpolation among known pixel values to obtain missing pixel values.

21. The method of claim 18, wherein,

Said first color, said second color, and said third color are each selected from the group consisting of cyan, magenta, and yellow.