Methods and apparatus to specify regions of interest in video frames
View Patent ↗Methods and apparatus to specify regions of interest in video frames are disclosed. An example disclosed method comprises determining an initial template region to represent a region of interest whose location is based on a first point selected in a graphical presentation, determining a first modification to perform on the initial template region in response to a second point selected in the graphical presentation, detecting the second selected point in the graphical presentation, and reshaping the initial template region toward the second selected point, the reshaping corresponding to the first modification, the reshaping being performed in response to detecting the second selected point without also requiring the user to select any point substantially on the boundary defining the initial template region to initiate the reshaping.
1. A method to mark a region of interest in a graphical presentation, the method comprising:
determining a first shape to define the region of interest, the first shape being positioned to include a first point in the graphical presentation;
detecting selection of a second point in the graphical presentation, the second point not being associated with a boundary defining the first shape; and
reshaping the first shape toward the second point to form a second shape to redefine the region of interest, the reshaping being performed in response detecting the selection of the second point.
2. A method as defined in claim 1 wherein the first shape bounds a first set of pixels in the graphical presentation that are connected to a starting pixel by neighboring pixels that are similar to the starting pixel, the starting pixel corresponding to the first point.
3. A method as defined in claim 2 further comprising identifying the first set of pixels recursively beginning with the starting pixel and iteratively including adjacent pixels having at least one of substantially similar luminance or chrominance relative to the starting pixel.
4. A method as defined in claim 1 wherein reshaping the first shape towards the second point comprises:
expanding the boundary defining the first shape uniformly to bound the second point when the second point is located outside the boundary of the first shape before the reshaping; and
shrinking the boundary defining the first shape uniformly to bound the second point when the second point is located inside the boundary of the first shape before the reshaping.
5. A method as defined in claim 1 wherein reshaping the first shape towards the second point comprises:
expanding the boundary defining the first shape uniformly by a unit step size when the second point is located outside the boundary of the first shape before the reshaping; and
shrinking the boundary defining the first shape uniformly by a unit step size when the second point is located inside the boundary of the first shape before the reshaping.
6. A method as defined in claim 1 wherein reshaping the first shape towards the second point comprises:
expanding the boundary defining the first shape in a first direction towards the second point and by a unit step size when the second point is located outside the boundary of the first shape before the reshaping; and
shrinking the boundary defining the first shape in a second direction towards the second point and by the unit step size when the second point is located inside the boundary of the first shape before the reshaping.
7. A method as defined in claim 1 wherein reshaping the first shape towards the second point comprises:
expanding the boundary defining the first shape in a first direction towards the second point to bound the second point when the second point is located outside the boundary of the first shape before the reshaping; and
shrinking the boundary defining first shape in a second direction towards the second point to bound the second point when the second point is located inside the boundary of the first shape prior to the reshaping.
8. A method as defined in claim 1 wherein the region of interest is a first region of interest and further comprising:
determining a third shape to define a second region of interest in the graphical representation, the second region of interest being different from the first region of interest; and
determining a fourth shape to define a third region of interest, the third region of interest including the first region of interest and the second region of interest, the fourth shape bounding the second shape defining the first region of interest and the third shape defining the second region of interest.
9. A tangible machine readable storage medium comprising machine readable instructions which, when executed, cause a machine to at least:
determine a first shape to define a region of interest in a graphical presentation, the first shape being positioned to include a first point in the graphical presentation;
detect selection of a second point in the graphical presentation, the second point not being associated with a boundary defining the first shape; and
reshape the first shape toward the second point to form a second shape to redefine the region of interest, the machine to perform the reshaping in response to detecting the selection of the second point.
10. A storage medium as defined in claim 9 wherein the first shape bounds a first set of pixels in the graphical presentation that are connected to a starting pixel by neighboring pixels that are similar to the starting pixel, the starting pixel corresponding to the first point, and the machine readable instructions, when executed, further cause the machine to identify the first set of pixels recursively beginning with the starting pixel and iteratively including adjacent pixels having at least one of substantially similar luminance or chrominance relative to the starting pixel.
11. A storage medium as defined in claim 9 wherein to reshape the first shape, the machine readable instructions, when executed, cause the machine to:
expand the boundary defining the first shape uniformly to bound the second point when the second point is located outside the boundary of the first shape before the first shape is reshaped; and
shrink the boundary defining the first shape uniformly to bound the second point when the second point is located inside the boundary of the first shape before the first shape is reshaped.
12. A storage medium as defined in claim 9 wherein to reshape the first shape, the machine readable instructions, when executed, cause the machine to:
expand the boundary defining the first shape uniformly by a unit step size when the second point is located outside the boundary of the first shape before the first shape is reshaped; and
shrink the boundary defining the first shape uniformly by a unit step size when the second point is located inside the boundary of the first shape before the first shape is reshaped.
13. A storage medium as defined in claim 9 wherein to reshape the first shape, the machine readable instructions, when executed, cause the machine to:
expand the boundary defining the first shape in a first direction towards the second point and by a unit step size when the second point is located outside the boundary of the first shape before the first shape is reshaped; and
shrink the boundary defining the first shape in a second direction towards the second point and by the unit step size when the second point is located inside the boundary of the first shape before the first shape is reshaped.
14. A storage medium as defined in claim 9 wherein to reshape the first shape, the machine readable instructions, when executed, cause the machine to:
expand the boundary defining the first shape in a first direction towards the second point to bound the second point when the second point is located outside the boundary of the first shape before the first shape is reshaped; and
shrink the boundary defining first shape in a second direction towards the second point to bound the second point when the second point is located inside the boundary of the first shape prior to the first shape is reshaped.
15. A storage medium as defined in claim 9 wherein the region of interest is a first region of interest and the machine readable instructions, when executed, cause the machine to:
determine a third shape to define a second region of interest in the graphical representation, the second region of interest being different from the first region of interest;
determine a fourth shape to define a third region of interest, the third region of interest including the first region of interest and the second region of interest, the fourth shape bounding the second shape defining the first region of interest and the third shape defining the second region of interest.
16. A system for marking a region of interest in a graphical presentation, the system comprising:
an output device to display the graphical presentation;
an input device to select points within the displayed graphical presentation; and
a processor to:
determine a first shape to define the region of interest, the first shape being positioned to include a first point in the graphical presentation using the input device;
detect selection of a second point in the graphical presentation using the input device, the second point not being associated with a boundary defining the first shape; and
reshape the first shape toward the second point to form a second shape to redefine the region of interest, the processor to perform the reshaping in response to detecting the selection of the second point.
17. A system as defined in claim 16 wherein the first shape bounds a first set of pixels in the graphical presentation that are connected to a starting pixel by neighboring pixels that are similar to the starting pixel, the starting pixel corresponding to the first point, and the processor is to identify the first set of pixels recursively beginning with the starting pixel and iteratively including adjacent pixels having at least one of substantially similar luminance or chrominance relative to the starting pixel.
18. A system as defined in claim 16 wherein to reshape the first shape, the processor is to:
expand the boundary defining the first shape towards the second point to bound the second point when the second point is located outside the boundary of the first shape before the first shape is reshaped; and
shrink the boundary defining the first shape towards the second point to bound the second point when the second point is located inside the boundary of the first shape before the first shape is reshaped.
19. A system as defined in claim 16 wherein to reshape the first shape, the processor is to:
expand the boundary defining the first shape towards the second point and by a unit step seize when the second point is located outside the boundary of the first shape before the first shape is reshaped; and
shrink the boundary defining the first shape towards the second point and by the unit step size when the second point is located inside the boundary of the first shape before the first shape is reshaped.
20. A system as defined in claim 16 wherein the region of interest is a first region of interest and the processor is to:
determine a third shape to define a second region of interest in the graphical representation, the second region of interest being different from the first region of interest;
determine a fourth shape to define a third region of interest, the third region of interest including the first region of interest and the second region of interest, the fourth shape bounding the second shape defining the first region of interest and the third shape defining the second region of interest.