Adjusting pixels by desired gains and factors

• US 20060023965A1
• Filed: 07/30/2004
• Published: 02/02/2006
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Kimbell, Benjamin D., Miller, Casey L.
• Granted Patent: US 7,426,314 B2
• Time in Patent Office: Days
• US Class Current: 382/260
• CPC Class Codes: H04N 1/58 Edge or detail enhancement; Noise or error suppression, e.g. colour misregistration correction H04N1/62 takes precedence

Abstract

A low frequency value for a pixel value is adjusted by a desired gain. A first high frequency value for the pixel value is calculated. A second high frequency value is generated for the first high frequency value. The second high frequency value is the first high frequency value adjusted by a factor. The factor is resolved as a function of the first high frequency value and the desired gain. A modified value for the pixel value is outputted, where the modified value is the adjusted low frequency value augmented by the second high frequency value.

Claims

1. A method comprising:

adjusting a low frequency value for a pixel value by a desired gain;

calculating a first high frequency value for the pixel value;

generating a second high frequency value as the first high frequency value adjusted by a factor, wherein the factor is a function of the first high frequency value and the desired gain; and

outputting a modified pixel value as the adjusted low frequency value augmented by the second high frequency value.

2. The method of claim 1 further comprising, processing a low pass filter on an image or portion of the image associated with the pixel value to acquire the low frequency value.

3. The method of claim 1 further comprising, iterating the method for each pixel of an image or portion of the image.

4. The method of claim 1 further comprising, receiving the desired gain as a configurable option for processing an image or portion of the image.

5. The method of claim 1, wherein adjusting the low frequency value further includes multiplying the low frequency value by the desired gain.

6. The method of claim 5, wherein calculating the first high frequency value further includes subtracting the low frequency value from the pixel value.

7. The method of claim 6, wherein generating a second high frequency value further includes determining, within the function, an adjustment to minimize noise, wherein the adjustment is the factor.

8. The method of claim 7, wherein generating the second high frequency value further includes setting the second high frequency value as the first high frequency multiplied by the desired gain, which is then further multiplied by the factor.

9. The method of claim 8, wherein outputting the modified pixel value further includes setting the modified pixel value as the adjusted low frequency value added to the second high frequency value.

10. The method of claim 1, wherein generating further includes determining the factor as a function of the first high frequency value, the desired gain, and the adjusted low frequency value.

11. A method comprising:

receiving a desired gain for processing an image or portion of the image;

iterating each pixel of the image or the portion of the image by;

adjusting a low frequency value for each pixel;

determining a high frequency value for each pixel;

modifying the high frequency value by a factor; and

saving a modified pixel for each pixel that is represented by the adjusted low frequency value added to the modified high frequency value; and

outputting a modified version of the image or portion of the image as a collection of the saved modified pixels.

12. The method of claim 11, wherein in receiving further includes receiving the desired gain for at least one of a luminance channel and a color channel.

13. The method of claim 11, wherein modifying further includes resolving the factor as a function of a first high frequency value, acquired by subtracting the low frequency value from an original value of the pixel being iterated, and the desired gain.

14. The method of claim 13, wherein modifying further includes:

comparing the first high frequency value multiplied by the desired gain to a first threshold if the comparison is at or below the first threshold then the factor is set to an inverse of the desired gain;

comparing the first high frequency value multiplied by the desired gain to a second threshold, if the comparison is at or above the second threshold then the factor is set to the desired gain; and

interpolating to acquire a value for the factor between the inverse of the desired gain and the desired gain if the first high frequency value is in between the first and second thresholds.

15. The method of claim 11, wherein the processing of the method is provided as a service over a network.

16. The method of claim 11, wherein the processing of the method is embedded within a device

21. The system of claim 16, wherein the high pass function compares the desired gain and an initial high pass frequency value to one or more thresholds to resolve a value for the factor.

22. The system of claim 21, wherein the high pass function assigns the factor a value represented by an inverse of the desired gain when the high pass frequency value multiplied by the desired gain compares to the a first threshold, and wherein the high pass function assigns the factor a value as the desired gain when the high pass frequency value multiplied by the desired gain compares to a second threshold.

17. A system, comprising:

a low pass function;

a high pass function, wherein the low pass function determines an adjusted low frequency value for a pixel value in response to a desired gain, and wherein the high pass function determines a high frequency value for the pixel value and then adjusted the high frequency value by a factor.

18. The system of claim 17 further comprising, an pixel modifier function that outputs a modified value for the pixel value represented by the sum of the adjusted low frequency value and the adjusted high frequency value.

19. The system of claim 17 further comprising, an administrative interface that provides an image or portion of the image associated with the pixel value and the desired gain to the system.

20. The system of claim 17, wherein the loss pass function is a low pass filter that averages values for surrounding pixels within a configurable area of the pixel value to acquire the low frequency value for the pixel value.

23. A system, comprising:

a low pass filter for acquiring an adjusted low frequency value for a pixel value in response to a desired gain;

means for determining a factor that adjusts a high frequency value for the pixel value; and

an output function that outputs a modified value for the pixel value as the adjusted low frequency value and the adjusted high frequency value.

24. The system of claim 23, wherein the means for determining further includes means for comparing the desired gain and a first high frequency value to one or more thresholds in order to assign a value to the factor.

25. The medium of claim 24, wherein the high frequency value is adjusted by multiplying the first high frequency value with the factor.

26. The system of claim 23, wherein the modified value represents a non linear adjustment to the pixel value.

27. A machine readable medium for modifying an image or portion of the image having instructions thereon, the instructions when executed performing the method comprising:

receiving a desired gain for an image or portion of the image;

calculating a low pass value for the image or portion of the image in response to the desired gain;

calculating a high pass value for the image or portion of the image;

modifying the high pass value by factors associated with each pixel of the image to minimize noise; and

outputting a modified version of the image or portion of the image representing the low pass value of the image or portion of the image added to the modified high pass value of the image or portion of the image.

28. The medium of claim 27 further comprising, installing the instructions on a server as a service that is accessible over a network.

29. The medium of claim 27 further comprising, installing the instructions on a device.

30. The medium of claim 27, wherein modifying further includes resolving the factors as a function of a first high frequency value calculated for each pixel and the desired gain.