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Ultrasound multipath background clutter mitigation based on subspace analysis and projection

improved performance in case of strong background clutter due to other people freely moving behind the actor. 1

reflections to enhance ultrasound imag-ing. In constructing the surface reflection, or clutter, subspace, we account for rough surface scatterings which, due to various possi-ble propagation time delays between the transmitter and receiver, expand the subspace dimension beyond that corresponding to ideal

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can handle situations where the back-ground of the scene is cluttered and not completely static but contains small motions such as tree branches and bushes. The model estimates the probability of observing pixel intensity values based on a sample of intensity values for each pixel. The model adapts

categories. These results clearly demonstrate that the method is robust to background clutter and produces good categorization accuracy even without exploiting geometric information. 1.

for classification of texture and object images under challenging real-world conditions, including significant intra-class variations and substantial background clutter.

presented, one with the training-flower scent and one with the training-flower shape. For each experi-mental repetition, we recorded which flower was located first, and then shifted flower posi-tions. Additionally, experiments were repeated in a simple environment, without background clutter, or a complex

is very useful for a variety of tasks, such as video surveillance, objectlevel video summarization, video indexing, digital library organization, etc. However, it remains a challenging task for computers to achieve robust action recognition due to cluttered background, camera motion, occlusion