Adaptive sampling region for a region editing tool
Properties of pixels in a digital image are sampled within different subdivisions of an editing tool impression to produce different property distributions. The different subdivisions can automatically alter their size, geometry, and/or location, based on image content within one or more of the subdivisions, in order to encompass a set of pixels having a substantially uniform distribution of a pixel property. Uniformity can be defined relative to the editing operation or context of the image. The property distributions from each region are classified to identify different edit classes within the property space, which are then used to apply an edit effect to the digital image within the tool impression. The edit classes may be represented by an edit profile in two or more dimensions.
1. A method comprising:
sampling pixels in a first region within a tool impression in a digital image to determine a first distribution of a pixel property of the pixels in the first region using a processing unit;
modifying the first region within the tool impression to encompass a set of additional pixels within the tool impression;
determining a second distribution of the pixel property based on the pixels in the modified first region using the processing unit;
sampling pixels in a second region within the tool impression to determine a third distribution of the pixel property of the pixels in the second region using the processing unit; and
editing at least one pixel within the tool impression based on the second and third distributions.
2. The method of claim 1 wherein the modifying operation is limited by a sampling criterion.
3. The method of claim 1 wherein the modifying operation is limited by a detection of an abrupt change in a pixel property trend within the first region.
4. The method of claim 1 wherein the modifying operation is limited by a sampling criterion based on a uniformity metric.
5. The method of claim 1 wherein the modifying operation is limited by a sampling criterion based on a pixel property trend in the first region.
6. The method of claim 1 wherein the modifying operation is limited by a sampling criterion based on a trend in a measure of variability of a pixel property in the first region.
7. The method of claim 1 wherein the modifying operation is limited by a sampling criterion based on a uniformity metric trend in the first region.
8. The method of claim 1 wherein the first distribution is characterized by a measure of variability and a measure of central tendency of pixel property difference, and the ratio of the measure of variability and the measure of central tendency of the pixel property difference is less than a defined threshold.
9. The method of claim 1 wherein the second distribution is characterized by a measure of variability and a measure of central tendency of pixel property difference and the ratio of the measure of variability and the measure of central tendency of pixel property difference is less than a defined threshold.
10. The method of claim 1 wherein the first region has an area and the modifying operation comprises:
increasing the area of the first region by one or more pixels to generate the modified first region.
11. The method of claim 1 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region uniformly to generate the modified first region.
12. The method of claim 1 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region non-uniformly to generate the modified first region.
13. The method of claim 1 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region uniformly in stages to generate the modified first region until a distribution of the pixel property of the set of pixels encompassed by the modified first region is no longer substantially uniform; and
reverting to the modified first region of a previous stage in which the distribution of the pixel property of the set of pixels encompassed by the modified first region is substantially uniform.
14. The method of claim 1 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region non-uniformly in stages to generate the modified first region until a distribution of the pixel property of the set of pixels encompassed by the modified first region is no longer substantially uniform; and
reverting to the modified first region of a previous stage in which the distribution of the pixel property of the set of pixels encompassed by the modified first region is substantially uniform.
15. The method of claim 1 wherein the first region has a periphery that defines an area and the modifying operation comprises:
growing the area of the first region to generate the modified first region.
16. The method of claim 1 wherein the first region has a periphery that defines an area and the modifying operation comprises:
growing the area of the first region without violating a sampling criterion to generate the modified first region.
17. A computer readable medium encoding a computer program for executing on a computer system a computer process, the computer process comprising:
sampling pixels in a first region within a tool impression in a digital image to determine a first distribution of a pixel property of the pixels in the first region;
modifying the first region within the tool impression to encompass a set of additional pixels within the tool impression;
determining a second distribution of the pixel property based on the pixels in the modified first region;
sampling pixels in a second region within the tool impression to determine a third distribution of the pixel property of the pixels in the second region; and
editing at least one pixel within the tool impression based on the second and third distributions.
18. The computer readable medium of claim 17 wherein the modifying operation is limited by a sampling criterion.
19. The computer readable medium of claim 17 wherein the modifying operation is limited by a detection of an abrupt change in a pixel property trend within the first region.
20. The computer readable medium of claim 17 wherein the modifying operation is limited by a sampling criterion based on a uniformity metric.
21. The computer readable medium of claim 17 wherein the modifying operation is limited by a sampling criterion based on a pixel property trend in the first region.
22. The computer readable medium of claim 17 wherein the modifying operation is limited by a sampling criterion based on a trend in a measure of variability of a pixel property in the first region.
23. The computer readable medium of claim 17 wherein the modifying operation is limited by a sampling criterion based on a uniformity metric trend in the first region.
24. The computer readable medium of claim 17 wherein the first distribution is characterized by a measure of variability and a measure of central tendency of pixel property difference, and the ratio of the measure of variability and the measure of central tendency of the pixel property difference is less than a defined threshold.
25. The computer readable medium of claim 17 wherein the second distribution is characterized by a measure of variability and a measure of central tendency of pixel property difference and the ratio of the measure of variability and the measure of central tendency of pixel property difference is less than a defined threshold.
26. The computer readable medium of claim 17 wherein the first region has an area and the modifying operation comprises:
increasing the area of the first region by one or more pixels to generate the modified first region.
27. The computer readable medium of claim 17 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region uniformly to generate the modified first region.
28. The computer readable medium of claim 17 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region non-uniformly to generate the modified first region.
29. The computer readable medium of claim 17 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region uniformly in stages to generate the modified first region until a distribution of the pixel property of the set of pixels encompassed by the modified first region is no longer substantially uniform; and
reverting to the modified first region of a previous stage in which the distribution of the pixel property of the set of pixels encompassed by the modified first region is substantially uniform.
30. The computer readable medium of claim 17 wherein the first region has a periphery and the modifying operation comprises:
modifying the periphery of the first region non-uniformly in stages to generate the modified first region until a distribution of the pixel property of the set of pixels encompassed by the modified first region is no longer substantially uniform; and
reverting to the modified first region of a previous stage in which the distribution of the pixel property of the set of pixels encompassed by the modified first region is substantially uniform.
31. The computer readable medium of claim 17 wherein the first region has a periphery that defines an area and the modifying operation comprises:
growing the area of the first region to generate the modified first region.
32. The computer readable medium of claim 17 wherein the first region has a periphery that defines an area and the modifying operation comprises:
growing the area of the first region without violating a sampling criterion to generate the modified first region.
33. A computer-readable medium encoding a computer program for execution on a computer system, the computer program comprising:
a region sampling module that samples pixels in a first region within a tool impression in a digital image to determine a first distribution of a pixel property of the pixels in the first region and samples pixels in a second region within the tool impression to determine a second distribution of the pixel property of the pixels in the second region;
an adaptive sampling region module that modifies the first region within the tool impression to encompass a set of additional pixels within the tool impression and determines a third distribution of the pixel property based on the pixels in the modified first region; and
an editing module that edits at least one pixel within the tool impression based on the second and third distributions.
34. The computer readable medium of claim 33 wherein the first region has a periphery and the adaptive sampling region module further modifies the periphery of the first region uniformly in stages to generate the modified first region until a distribution of the pixel property of the set of pixels encompassed by the modified first region is no longer substantially uniform, and reverts to the modified first region of a previous stage in which the distribution of the pixel property of the set of pixels encompassed by the modified first region is substantially uniform.
35. A system comprising:
means for sampling pixels in a first region within a tool impression in a digital image to determine a first distribution of a pixel property of the pixels in the first region;
means for modifying the first region within the tool impression to encompass a set of additional pixels within the tool impression;
means for determining a second distribution of the pixel property based on the pixels in the modified first region;
means for sampling pixels in a second region within the tool impression to determine a third distribution of the pixel property of the pixels in the second region; and
means for editing at least one pixel within the tool impression based on the second and third distributions.
36. The system of claim 35 wherein the first region has a periphery and the means for modifying comprise:
means for modifying the periphery of the first region in stages to generate the modified first region until a distribution of the pixel property of the set of pixels encompassed by the modified first region is no longer substantially uniform; and
means for reverting to the modified first region of a previous stage in which the distribution of the pixel property of the set of pixels encompassed by the modified first region is substantially uniform.