Abstract: Reconstruction method for reconstructing a first signal (x(t)) regularly sampled at a sub-Nyquist rate, comprising the step of retrieving from the regularly spaced sampled values (ys[n], y(nT)) a set of weights (cn, cnr, ck) and shifts (tn, tk) with which said first signal (x(t)) can be reconstructed. The reconstructed signal (x(t)) can be represented as a sequence of known functions (?(t)) weighted by the weigths (ck) and shifted by the shifts (tk). The sampling rate is at least equal to the rate of innovation (?) of the first signal (x(t)).

Abstract: Standard video footage even from a single video camera can be used to obtain, in an automated fashion, a stroboscope sequence of a sports event, for example. The sequence may be represented as a static images of a photographic nature, or by a video sequence in which camera motion remains present, in which case the video sequence can be rendered as a panning camera movement on a stroboscope picture or as an animated stroboscope sequence in which the moving object leaves a trailing trace of copies along its path. Multiple cameras can be used for an expanded field of view or for comparison of multiple sequences, for example.

Abstract: Reconstruction method and devices for two-dimensional signals that are not bandlimited but have a parametric representation with a finite number of degrees of freedom. The signal is reconstructed from the samples obtained after a suitable filtering with a smoothing kernel. Projection techniques allow reducing the problem to a combination of one-dimensional subproblems.

Abstract: A method for determining the relative position of wireless terminals (1) in an ad hoc network, wherein at least some of said wireless terminals can communicate over wireless links (2) in one or several hops with at least some of the other wireless terminals. The following steps are performed in the wireless terminals: (1) measuring in a plurality of said wireless terminals the distances (dij) to one-hop neighbors, and (2) using the distances measured in at least two wireless terminals to compute the location (x, y) of at least one other wireless terminals. One advantage of the invention is GPS-less positioning in ad hoc networks.

Abstract: Standard video footage even from a single video camera can be used to obtain, in an automated fashion, a stroboscope sequence of a sports event, for example. The sequence may be represented as a static images of a photographic nature, or by a video sequence in which camera motion remains present, in which case the video sequence can be rendered as a panning camera movement on a stroboscope picture or as an animated stroboscope sequence in which the moving object leaves a trailing trace of copies along its path. Multiple cameras can be used for an expanded field of view or for comparison of multiple sequences, for example.

Abstract: Processing of quadtree data structures is significantly improved with the use of an indexing that is arranged to insure that the index value of a node in column/row i and column/row j differs from the index value of a node in column/row k and row/column i by a value that is constant. With such an indexing arrangement, no indexing information, or pointer information, needs to be stored. Moreover, traversal from any node to any other node can be accomplished with a single calculation followed by a single traversal which, in the context of this disclosure, is considered to be a single step.

Abstract: In a view, e.g. of scenery, of a shopping or museum display, or of a meeting or conference, automated processing can be used to annotate objects which are visible from a viewer position. Annotation can be of objects selected by the viewer, and can be displayed visually, for example, with or without an image of the view.

Abstract: A multiple description (MD) joint source-channel (JSC) encoder in accordance with the invention encodes n components of an image signal for transmission over m channels of a communication medium. In an illustrative embodiment which uses statistical redundancy between the different descriptions of the image signal, the encoder forms vectors from transform coefficients of the image signal separated both in frequency and in space. The vectors may be formed such that the spatial separation between the transform coefficients is maximized. A correlating transform is then applied, followed by entropy coding, grouping as a function of frequency, and application of a cascade transform. In an illustrative embodiment which uses deterministic redundancy between the different descriptions of the image signal, the encoder may apply a linear transform, followed by quantization, to generate the multiple descriptions of the image signal.

Abstract: Given two video sequences, a composite video sequence can be generated which includes visual elements from each of the given sequences, suitably synchronized and represented in a chosen focal plane. For example, given two video sequences with each showing a different contestant individually racing the same down-hill course, the composite sequence can include elements from each of the given sequences to show the contestants as if racing simultaneously. A composite video sequence can be made also by similarly combining a video sequence with an audio sequence.

Abstract: A multiple description (MD) joint source-channel (JSC) encoder in accordance with the invention encodes n components of an image signal for transmission over m channels of a communication medium. In an illustrative embodiment which uses statistical redundancy between the different descriptions of the image signal, the encoder forms vectors from transform coefficients of the image signal separated both in frequency and in space. The vectors may be formed such that the spatial separation between the transform coefficients is maximized. A correlating transform is then applied, followed by entropy coding, grouping as a function of frequency, and application of a cascade transform. In an illustrative embodiment which uses deterministic redundancy between the different descriptions of the image signal, the encoder may apply a linear transform, followed by quantization, to generate the multiple descriptions of the image signal.

Abstract: For annotating a digital image with information from a digital map, features which are visible from a viewer position are extracted from the map. The extracted features are matched with corresponding features in the image, and feature annotations are transferred from the map to the image to obtain an integrated view. The technique facilitates the annotation of photographs, and it can be included in navigation and simulation systems.

Abstract: For encoding signals corresponding to still images or video sequences, respective standards known as JPEG and MPEG have been proposed. These standards are based on digital cosine transform (DCT) compression. For economy of transmission, DCT coefficients may be "thresholded" prior to transmission, by dropping the less significant DCT coefficients. While maintaining JPEG or MPEG compatibility, threshold selection for the DCT coefficients of an image or video frame is based on optimizing for minimum distortion for a specified maximum target coding bit rate or, equivalently, for minimized coding bit rate for a specified maximum allowable distortion constraint. In the selection process, a dynamic programming method is used.

Abstract: A filter bank comprising first and second finite impulse response diamond-shaped filters with finite precision filter coefficients is used to convert a high definition progressive video sequence in a vertical-time representation into an interlaced sequence and a deinterlacing sequence. The interlaced sequence may be used by a low resolution television receiver to display a low resolution television image. The interlaced and deinterlacing sequences may be recombined to perfectly reconstruct the progressive high definition video sequence which then may be used by a high definition television receiver. Thus, the inventive system has the advantage that it enables a single high definition video sequence to be utilized by both high definition television equipment and lower resolution television equipment so that an existing base of consumer television equipment is not rendered obsolete by the introduction of a high definition television sequence.

Abstract: An echo cancelling device for use between a line receiving an incoming signal and a line transmitting an outgoing signal, for cancelling out echo, comprising a plurality of processing channels connected in parallel relation and assigned to successive mutually adjacent sub-bands of the spectral band of the outgoing signal, each channel having: a first analysis band-pass filter receiving the echo-affected signal to be transmitted, whose output is connected to the additive input of a subtractor; a second analysis band-pass filter, identical to the first filter, receiving the incoming signal and feeding an adaptive filter delivering an estimated echo value in the sub-band to the subtractive input of the subtractor; and a synthesis filter, symmetrical with the analysis filters and whose output feeds the transmission line.