Recent Patents in Signal Processing (December 2017) – Active Contours

For our December 2017 issue, we cover recent patents granted in the area of applications of active contours.

Patent no 9,607,241 presents a system and method for active contour segmentation. An image of a first and at least a second structure, a first position for the first structure, and at least a second position for the at least second structure are received, the first and the at least second positions are set as a first and an at least second initial contour, and the first and the at least second initial contours are concurrently and iteratively deformed to respectively expand into a first and at least a second expanded contour matching a shape of the first and the at least second structure by applying constraints to each point of the first and the at least second initial contour, comprising a constraint for preventing the first and at least one of the at least second initial contour from intersecting one another upon being deformed, and the constraints are updated after each iteration.

The invention no. 9,495,756 introduces a system and method for active contour segmentation where an image for a structure and an initial position on the image are received, a multi-scale image representation comprising successive image levels each having associated therewith a representation of the image is computed, a representation of the image at a given level having a different image resolution than that of a representation of the image at a subsequent level, a given one of the levels at which noise in the image is removed is identified, the initial position is set as a current contour and the given level as a current level, the current contour is deformed at the current level to expand into an expanded contour matching a shape of the structure, the expanded contour is set as the current contour and the subsequent level as the current level, and the steps are repeated until the last level is reached.

In the invention no. 9,142,184 a device receives an image for an active contour model, where the active contour model includes a first module and a second module. The device receives an initial contour for the image and the active contour model, and executes a speed function of the first module, based on the image and the initial contour, to generate a speed function result. The device executes a numerical minimization method of the second module, based on the image and the speed function result, to generate a final contour, and provides the image and the final contour for display.

In patent no. 9,076,223 a device is configured to determine a contour vector that delineates an object in an image from a remaining portion of the image, and to generate a hash value by applying a hash function to the contour vector. The device is configured to compare the hash value to a previous hash value generated by applying the hash function to a previous contour vector, where the previous contour vector is determined prior to determining the contour vector. The device is configured to determine that the hash value matches the previous hash value and, based on determining that the hash value matches the previous hash value, segment the image using the contour vector.

In patent no. 8,942,441 a computer-implemented segmentation method is used to process an image representing a plurality of nuclei. The method is implemented in a computer having a processor and a physical memory. A set of instructions are provided to the processor the physical memory of the computer. The processor is configured by executing the set of instructions in the physical memory so as to automatically segment the image by: thresholding a grey-scale image to create a black and white image; identifying objects in the black and white image and removing objects failing to meet predetermined criteria; extracting objects; and applying an edge detector on the segmented image to identify the edges of the nuclei. Overlapping nuclei are split to improve results.

Patent no. 8,811,679 presents a method for realigning network elements in a digital map based on a new data set using active contour manipulation techniques. The active contour optimization process is controlled so that certain desirable features in the original shape of the active contour(s) are not distorted. In the case of network features which may be represented by two or more open active contours, the active contours are coupled prior to optimizing so that the original desirable shape, e.g., the parallel spacing of lanes in a dual carriageway road, may be maintained during the optimization process. In the case of certain closed active contours, for example roundabout geometries, a single closed active contour may be coupled to itself by linking its control points one-to-another and maintaining a proportional direction and distance movement during the optimizing process. As a result, data base networks can be assessed and aligned with less difficulty and geometric distortion.

In the patent no. 8,781,160 a method of image object tracking and segmentation is provided. The method includes defining an initial contour for tracking an image object and partitioning the initial contour into a plurality of contour segments. The method also includes estimating a weighted length of each of the plurality of contour segments and generating a desired contour by converging the plurality of contour segments to a plurality of edges of the image object using the estimated weighted length.

If you have an interesting patent to share when we next feature patents related to active contours, or if you are especially interested in a signal processing research field that you would want to be highlighted in this section, please send email to Csaba Benedek (benedek.csaba AT sztaki DOT mta DOT hu).

References

Number: 9,607,241
Title: Concurrent active contour segmentation
Inventors: Rivet-Sabourin; Geoffroy (Stoneham, CA)
Issued: March 28, 2017
Assignee: Laboratories Bodycad Inc. (Quebec, Quebec, CA)

Number: 9,495,756
Title: Multi-scale active contour segmentation
Inventors: Rivet-Sabourin; Geoffroy (Stoneham, CA)
Issued: November 15, 2016
Assignee: Laboratories Bodycad Inc. (Quebec, Quebec, CA)

Number: 9,142,184
Title: Speed function module and numerical minimization module for an active contour model
Inventors: Tiwari; Spandan (Framingham, MA), Eddins; Steven L. (Milford, MA), Mather; Jeff D. (Milford, MA), Taylor; Alexander J. (Jamaica Plain, MA), Uthama; Ashish (Arlington, MA), Yale; Mara M. (Framingham, MA)
Issued: September 22, 2015
Assignee: The MathWorks, Inc. (Natick, MA)

Number: 9,076,223
Title: Fast stopping criterion for active contour algorithms
Inventors: Tiwari; Spandan (Framingham, MA), Eddins; Steven L. (Milford, MA)
Issued: July 7, 2015
Assignee: The MathWorks, Inc. (Natick, MA)

Number: 8,942,441
Title: Optimizing the initialization and convergence of active contours for segmentation of cell nuclei in histological sections
Inventors: Nielsen; Birgitte (Oslo, NO), Maddison; John (Sussex, GB), Danielsen; Havard (Oslo, NO)
Issued: January 27, 2015
Assignee: Institute for Medical Informatics (Oslo, NO)

Number: 8,811,679
Title: Digital map editing process using active contour manipulation
Inventors: Bekaert; Tim (Heule, BE), Clarysse; Pascal (Koksijde, BE)
Issued: August 19, 2014
Assignee: TomTom Belgium N.V. (Gent, BE)

Number: 8,781,160
Title: Image object tracking and segmentation using active contours
Inventors: Viswanathan; Srikrishnan (Mumbai, IN), Chaudhuri; Subhasis (Mumbai, IN)
Issued: July 15, 2014
Assignee: Indian Institute of Technology Bombay (Powai, Mumbai, IN)