Method and Apparatus for Pattern Tracking

Abstract

A method and apparatus for pattern tracking. The method includes the steps of performing a foreground detection process to determine a hand-pill-hand region, performing image segmentation to separate the determined hand portion of the hand-pill-hand region from the pill portion thereof, building three reference models, one for each hand region and one for the pill region, initializing a dynamic model for tracking the hand-pill-hand region, determining N possible next positions for the hand-pill-hand region, for each such determined position, determining various features, building a new model for that region in accordance with the determined position, for each position, comparing the new model and a reference model, determining a position whose new model generates a highest similarity score, determining whether that similarity score is greater than a predetermined threshold, and wherein if it is determined that the similarity score is greater than the predetermined threshold, the object is tracked.

What is claimed: 
     
         1 . A method for tracking a pill in a patient's hand, comprising:
 performing a foreground detection process to determine a hand-pill-hand region;   performing image segmentation to separate the determined hand portion of the hand-pill-hand region from the pill portion thereof;   building three reference models, one for each hand region and one for the pill region;   initializing a dynamic model for tracking the hand-pill-hand region;   determining N possible next positions for the hand-pill-hand region;   for each such determined position, determining various features to be employed in a comparison to a reference model;   building a new model for that region in accordance with the determined position;   for each position, comparing the new model and the reference model;   determining a position whose new model generates a highest similarity score;   determining whether that similarity score is greater than a predetermined threshold;   wherein if it is determined that the similarity score is greater than the predetermined threshold, the object is tracked.   
     
     
         2 . The method of  claim 1 , wherein the reference models are combined into a single reference model. 
     
     
         3 . The method of  claim 1 , wherein the feature may be selected from the group of:
 shape, color, texture, gray-scale intensity and histogram of colors.   
     
     
         4 . A method for tracking a pill in a patient's hand, comprising the steps of:
 performing a foreground detection process of an image or series of images to determine a hand-pill-hand region;   performing image segmentation of the image or sequence of images to separate the determined hand portion of the hand-pill-hand region from the pill portion thereof;   building one or more reference models including at least the hand region and the pill region;   determining a feature vector of the hand hand-pill-hand region;   comparing the determined feature vector to one or more reference feature vectors;   determining a distance between the determined feature vector and each of the one or more reference feature vectors; and   determining an image or set of images corresponding to the determined feature vector to be similar to an image or set of images whose corresponding feature vector when the determined distance is less than a predetermined threshold.   
     
     
         5 . The method of  claim 4 , further comprising the step of fitting each determined distance into a Gaussian distribution to determine a confidence probability of a match between the two corresponding images or sets of images. 
     
     
         6 . A method for tracking a pill in a user's hand comprising the steps of:
 acquiring one or more images;   determining a hand-pill-hand portion of one or more of the acquired images;   storing an indication of one or more characteristics of and   determining a location of the hand-pill-hand portion in a next one or more of the acquired images in accordance with the one or more stored indications.   
     
     
         7 . The method of  claim 6 , further comprising the step of storing a color signature of the hand-pill-hand portion of the one or more of the acquired images as the indication of the one or more characteristics. 
     
     
         8 . The method of  claim 7 , further comprising the step of determining the location of the hand-pill-hand portion in a next one or more of the acquired images in accordance with the stored color signature. 
     
     
         9 . The method of  claim 7 , further comprising the step of distinguishing a pill colored similarly to a background in accordance with the stored color signature. 
     
     
         10 . The method of  claim 9 , wherein the background is a user shirt. 
     
     
         11 . The method of  9 , wherein the background is an environmental surface. 
     
     
         12 . The method of  claim 6 , wherein the step of determining a hand-pill-hand portion of one or more of the acquired images further comprises the steps of:
 performing a foreground detection process of an image or series of images to determine a hand-pill-hand region;   performing image segmentation of the image or sequence of images to separate the determined hand portion of the hand-pill-hand region from the pill portion thereof; and   building one or more reference models including at least one of the hand region and the pill region.   
     
     
         13 . The method of  claim 12 , wherein the method of  claim 12  further comprises the step of determining a feature vector difference between at least one of the one or more reference models and a hand-pill-hand portion of one or more of the one or more acquired images. 
     
     
         14 . The method of  claim 13 , wherein if the vector difference is less than a predetermined threshold, there is determined to be a match. 
     
     
         15 . The method of  claim 12 , wherein the foreground detection process takes into account one or more environmental factors. 
     
     
         16 . The method of  claim 15 , wherein the one or more environmental factors comprises ambient light. 
     
     
         17 . The method of  claim 6 , wherein the one or more characteristics comprises shape. 
     
     
         18 . The method of  claim 6 , wherein the one or more characteristics comprises color. 
     
     
         19 . The method of  claim 6 , further comprising repeating the processing for a plurality of consecutive acquired images. 
     
     
         20 . The method of  claim 19 , wherein processing is performed on a subset of the plurality of consecutive acquired images.