GesRec3D: a real-time coded gesture-to-speech system with automatic segmentation and recognition thresholding using dissimilarity measures

A complete microcomputer system is described, GesRec3D, which facilitates the data acquisition, segmentation, learning, and recognition of 3-Dimensional arm gestures, with application as a Augmentative and Alternative Communication (AAC) aid for people with motor and speech disability. The gesture data is acquired from a Polhemus electro-magnetic tracker system, with sensors attached to the finger, wrist and elbow of one arm. Coded gestures are linked to user-defined text, to be spoken by a text-to-speech engine that is integrated into the system. A segmentation method and an algorithm for classification are presented that includes acceptance/rejection thresholds based on intra-class and inter-class dissimilarity measures. Results of recognition hits, confusion misses and rejection misses are given for two experiments, involving predefined and arbitrary 3D gestures

Pen-Based Gestures: An Approach to Reducing Screen Clutter in Mobile Computing

Mobile computing is an area of high growth despite having some serious design issues. It is difficult to increase the size of the screen because of the device’s physical constraints. Consequently, as mobile applications have incorporated more functionality, screen clutter has increased. One method of reducing clutter is to remove visual controls and use pen-based gestures instead. We describe a cinema listing application for a Palm OS device that implements pen-based gestures as the main input method. Two methods are used to communicate the options available on each screen: audio cues and small visual prompts. Preliminary results suggest that buttons can be removed from the screen without detriment to task accuracy or user performance

Visual migraine aura with or without headache: association with right to left shunt and assessment following transcutaneous closure.

BackgroundRight to left shunting, usually caused by a patent foramen ovale (PFO), is associated with migraine and visual aura. It is unknown if patients who present with visual aura without headache behave similarly to those experiencing typical migraine headache with aura. The purpose of this study was to assess the prevalence of right to left shunting in patients who present with migraine aura without headache and evaluate the response to PFO closure.MethodsThe records of patients referred to the Interventional Cardiology program at the University of California at Los Angeles for suspected intracardiac right to left shunt were reviewed. Individuals with visual auras with or without migraine headaches were divided into three groups: group A (aura + migraine), migraine aura during or within 60 minutes of headache; group B (migraine aura unrelated to headache), migraine aura and headache temporally unrelated; and group C (migraine aura only), isolated migraine visual aura without a history of headaches. The presence of right to left shunt was assessed using transcranial Doppler with an agitated saline test. PFO closure was performed in 80 patients. Residual headache and migraine visual aura were assessed 3 and 12 months after the procedure. The control group consisted of 200 patients referred for diagnostic cardiac catheterization.ResultsOf 590 referred patients, 225 had migraine visual aura with or without headache. The prevalence of right to left shunt was similar (P = 0.66) in groups B (21/29, 72%) and C (14/21, 67%). Group A patients had a higher prevalence of right to left shunt (168/175, 96%) due to selection bias. The prevalence of right to left shunt in the control group was significantly (P < 0.0001) lower (36/200, 18%) than in groups A, B, and C. At 12 months after PFO closure, visual aura was resolved in 52%, 75%, and 80% of patients in groups A, B, and C, respectively (difference not statistically significant).ConclusionThere is an increased prevalence of PFO among patients with migraine aura without headache. The closure of PFO correlates with improvement of the visual aura, suggesting a causative association between the presence of PFO and both visual aura and migraine headaches. Ophthalmologists should be aware of the association of right to left shunts with visual aura

Visual migraine aura with or without headache: association with right to left shunt and assessment following transcutaneous closure.

BackgroundRight to left shunting, usually caused by a patent foramen ovale (PFO), is associated with migraine and visual aura. It is unknown if patients who present with visual aura without headache behave similarly to those experiencing typical migraine headache with aura. The purpose of this study was to assess the prevalence of right to left shunting in patients who present with migraine aura without headache and evaluate the response to PFO closure.MethodsThe records of patients referred to the Interventional Cardiology program at the University of California at Los Angeles for suspected intracardiac right to left shunt were reviewed. Individuals with visual auras with or without migraine headaches were divided into three groups: group A (aura + migraine), migraine aura during or within 60 minutes of headache; group B (migraine aura unrelated to headache), migraine aura and headache temporally unrelated; and group C (migraine aura only), isolated migraine visual aura without a history of headaches. The presence of right to left shunt was assessed using transcranial Doppler with an agitated saline test. PFO closure was performed in 80 patients. Residual headache and migraine visual aura were assessed 3 and 12 months after the procedure. The control group consisted of 200 patients referred for diagnostic cardiac catheterization.ResultsOf 590 referred patients, 225 had migraine visual aura with or without headache. The prevalence of right to left shunt was similar (P = 0.66) in groups B (21/29, 72%) and C (14/21, 67%). Group A patients had a higher prevalence of right to left shunt (168/175, 96%) due to selection bias. The prevalence of right to left shunt in the control group was significantly (P < 0.0001) lower (36/200, 18%) than in groups A, B, and C. At 12 months after PFO closure, visual aura was resolved in 52%, 75%, and 80% of patients in groups A, B, and C, respectively (difference not statistically significant).ConclusionThere is an increased prevalence of PFO among patients with migraine aura without headache. The closure of PFO correlates with improvement of the visual aura, suggesting a causative association between the presence of PFO and both visual aura and migraine headaches. Ophthalmologists should be aware of the association of right to left shunts with visual aura

The Issues of 3D Hand Gesture and Posture Recognition Using the Kinect

International audienceBesides the emergence of many input devices and sensors, they are still unable to provide good and simple recognition of human postures and gestures. The recognition using simple algorithms implemented on top of these devices (like the Kinect) enlarges use cases for these gestures and postures to newer domains and systems. Our methods cuts the needed computation and allow the integration of other algorithms to run in parallel. We present a system able to track the hand in 3D, log its position and surface information during the time, and recognize hand postures and gestures. We present our solution based on simple geometric algorithms, other tried algorithms, and we discuss some concepts raised from our tests