Abstract: Described herein are various technologies pertaining to diagnosing and/or prescribing treatment for osteoporosis. A bone of a patient is subjected to an MRI scan, and the resultant signal is subjected to a likelihood function. The output of the likelihood function are values that are parameters that are employed to ascertain connectivity of trabeculae in the bone of the patient and volumetric trabecular density of the bone.

Abstract: Image labeling with global parameters is described. In an embodiment a pose estimation system executes automatic body part labeling. For example, the system may compute joint recognition or body part segmentation for a gaming application. In another example, the system may compute organ labels for a medical imaging application. In an example, at least one global parameter, for example body height is computed for each of the images to be labeled. In an example, the global parameter is used to modify an image labeling process. For example the global parameter may be used to modify the input image to a canonical scale. In another example, the global parameter may be used to adaptively modify previously stored parameters of the image labeling process. In an example, the previously stored parameters may be computed from a reduced set of training data.

Abstract: An image processing system is described which automatically labels image elements of a digital image. In an embodiment an energy function describing the quality of possible labelings of an image is globally optimized to find an output labeled image. In the embodiment, the energy function comprises terms that depend on at least one non-local parameter. For example, the non-local parameter describes characteristics of image elements having the same label. In an embodiment the global optimization is achieved in a practical, efficient manner by using a tree structure to represent candidate values of the non-local parameter and by using a branch and bound process. In some embodiments, the branch and bound process comprises evaluating a lower bound of the energy function by using a min-cut process. For example, the min-cut process enables the lower bound to be evaluated efficiently using a graphical data structure to represent the lower bound.

Abstract: A method of segmenting image elements into a foreground and background is described, such that only the foreground elements are part of a volume of interest for stereo matching. This reduces computational burden as compared with computing stereo matching over the whole image. An energy function is defined using a probabilistic framework and that energy function approximated to require computation only over foreground disparities. An optimization algorithm is used on the energy function to perform the segmentation.

Abstract: Existing remote workspace sharing systems are difficult to use. For example, changes made on a common work product by one user often appear abruptly on displays viewed by remote users. As a result the interaction is perceived as unnatural by the users and is often inefficient. Images of a display of a common work product are received from a camera at a first location. These images may also comprise information about objects between the display and the camera such as a user's hand editing a document on a tablet PC. These images are combined with images of the shared work product and displayed at remote locations. Advance information about remote user actions is then visible and facilitates collaborative mediation between users. Depth information may be used to influence the process of combining the images.

Abstract: A real-time stereo video signal of a captured scene with a physical foreground object and a physical background is received. In real-time, a foreground/background separation algorithm is used on the real-time stereo video signal to identify pixels from the stereo video signal that represent the physical foreground object. A video sequence may be produced by rendering a 3D virtual reality based on the identified pixels of the physical foreground object.

Abstract: A slurry distributor comprises a slurry delivery pipe (B) to which, in use, the slurry is supplied, the slurry delivery pipe having a longitudinally extending slot (E). There is an injector rotor (A) within which the slurry delivery pipe (B) is disposed, a plurality of tines (C) and a plurality of outlet ports (D) on the injector rotor (A). The tines (C) are adapted for cutting into the soil upon movement of the injector rotor (A) over the soil surface and the arrangement is such that, as the outlet ports (D) of the injector rotor (A) pass the slot (E) during rotation of the injector rotor (A) relative to the slurry delivery pipe (B), the slurry will pass through the slot (E) into the outlet ports (D).

Abstract: Existing remote workspace sharing systems are difficult to use. For example, changes made on a common work product by one user often appear abruptly on displays viewed by remote users. As a result the interaction is perceived as unnatural by the users and is often inefficient. Images of a display of a common work product are received from a camera at a first location. These images may also comprise information about objects between the display and the camera such as a user's hand editing a document on a tablet PC. These images are combined with images of the shared work product and displayed at remote locations. Advance information about remote user actions is then visible and facilitates collaborative mediation between users. Depth information may be used to influence the process of combining the images.

Abstract: Segmentation of foreground from background layers in an image may be provided by a segmentation process which may be based on one or more factors including motion, color, contrast, and the like. Color, motion, and optionally contrast information may be probabilistically fused to infer foreground and/or background layers accurately and efficiently. A likelihood of motion vs. non-motion may be automatically learned from training data and then fused with a contrast-sensitive color model. Segmentation may then be solved efficiently by an optimization algorithm such as a graph cut. Motion events in image sequences may be detected without explicit velocity computation.

Abstract: A real-time stereo video signal of a captured scene with a physical foreground object and a physical background is received. In real-time, a foreground/background separation algorithm is used on the real-time stereo video signal to identify pixels from the stereo video signal that represent the physical foreground object. A video sequence is produced by rendering a 3d virtual reality based on the identified pixels of the physical foreground object.

Abstract: Image segmentation using star-convexity constraints is described. In an example, user input specifies positions of one or more star centers in a foreground to be segmented from a background of an image. In embodiments, an energy function is used to express the problem of segmenting the image and that energy function incorporates a star-convexity constraint which limits the number of possible solutions. For example, the star-convexity constraint may be that, for any point p inside the foreground, all points on a shortest path (which may be geodesic or Euclidean) between the nearest star center and p also lie inside the foreground. In some examples continuous star centers such as lines are used. In embodiments a user may iteratively edit the star centers by adding brush strokes to the image in order to progressively change the star-convexity constraints and obtain an accurate segmentation.

Abstract: Previously, Poisson blending has been used for image blending including cloning an object onto a target background and blending pairs of source images together. Such Poisson blending works well in many situations. However, whilst this method is always workable, we have found that discolorations sometimes occur. We realized that these discolorations occur when the gradient of the source image is preserved too insistently, at the expense of preserving object and background color. In some situations object outlines become smeared or blurred. We develop a color preservation term and a fragility measure to address these problems. This gives a user additional control to obtain smooth compositions and reduce discoloration artifacts.

Abstract: Methods of image segmentation using reduced foreground training data are described. In an embodiment, the foreground and background training data for use in segmentation of an image is determined by optimization of a modified energy function. The modified energy function is the energy function used in image segmentation with an additional term comprising a scalar value. The optimization is performed for different values of the scalar to produce multiple initial segmentations and one of these segmentations is selected based on pre-defined criteria. The training data is then used in segmenting the image. In other embodiments further methods are described: one places an ellipse inside the user-defined bounding box to define the background training data and another uses a comparison of properties of neighboring image elements, where one is outside the user-defined bounding box, to reduce the foreground training data.

Abstract: Methods of updating image segmentation following user input are described. In an embodiment, the properties used in computing the different portions of the image are updated as a result of one or more user inputs. Image elements which have been identified by a user input are given more weight when updating the properties than other image elements which have already been assigned to a particular portion of the image. In another embodiment, an updated segmentation is post-processed such that only regions which are connected to an appropriate user input are updated.

Abstract: Real-time segmentation of foreground from background layers in binocular video sequences may be provided by a segmentation process which may be based on one or more factors including likelihoods for stereo-matching, color, and optionally contrast, which may be fused to infer foreground and/or background layers accurately and efficiently. In one example, the stereo image may be segmented into foreground, background, and/or occluded regions using stereo disparities. The stereo-match likelihood may be fused with a contrast sensitive color model that is initialized or learned from training data. Segmentation may then be solved by an optimization algorithm such as dynamic programming or graph cut. In a second example, the stereo-match likelihood may be marginalized over foreground and background hypotheses, and fused with a contrast-sensitive color model that is initialized or learned from training data. Segmentation may then be solved by an optimization algorithm such as a binary graph cut.

Abstract: A method of labeling pixels in an image is described where the pixel label is selected from a set of three or more labels. The pixel labeling problem is reduced to a sequence of binary optimizations by representing the label value for each pixel as a binary word and then optimizing the value of each bit within the word, starting with the most significant bit. Data which has been learned from one or more training images is used in the optimization to provide information about the less significant bits within the word.

Abstract: A method of labeling pixels in an image is described where the pixel label is selected from a set of three or more labels. The pixel labeling problem is reduced to a sequence of binary optimizations by representing the label value for each pixel as a binary word and then optimizing the value of each bit within the word, starting with the most significant bit. Data which has been learned from one or more training images is used in the optimization to provide information about the less significant bits within the word.

Abstract: A multi-layer graph for dense stereo dynamic programming can improve synthesis of cyclopean virtual images by distinguishing between stereo disparities caused by occlusion and disparities caused by non-fronto-parallel surfaces. This distinction can be leveraged to reduce image artifacts, such as “halos”. Distinguishing at least between these two types of disparities allows improved matching of left and right pixel data, which increases the amount of correct pixel information used in constructing the cyclopean virtual image and minimizes occlusion artifacts.

Abstract: Real-time segmentation of foreground from background layers in binocular video sequences may be provided by a segmentation process which may be based on one or more factors including likelihoods for stereo-matching, color, and optionally contrast, which may be fused to infer foreground and/or background layers accurately and efficiently. In one example, the stereo image may be segmented into foreground, background, and/or occluded regions using stereo disparities. The stereo-match likelihood may be fused with a contrast sensitive color model that is initialized or learned from training data. Segmentation may then be solved by an optimization algorithm such as dynamic programming or graph cut. In a second example, the stereo-match likelihood may be marginalized over foreground and background hypotheses, and fused with a contrast-sensitive color model that is initialized or learned from training data. Segmentation may then be solved by an optimization algorithm such as a binary graph cut.

Abstract: An image processing system is described which automatically labels image elements of a digital image. In an embodiment an energy function describing the quality of possible labelings of an image is globally optimized to find an output labeled image. In the embodiment, the energy function comprises terms that depend on at least one non-local parameter. For example, the non-local parameter describes characteristics of image elements having the same label. In an embodiment the global optimization is achieved in a practical, efficient manner by using a tree structure to represent candidate values of the non-local parameter and by using a branch and bound process. In some embodiments, the branch and bound process comprises evaluating a lower bound of the energy function by using a min-cut process. For example, the min-cut process enables the lower bound to be evaluated efficiently using a graphical data structure to represent the lower bound.