44 results about "Steerable filter" patented technology

A listening device for a hearing impaired person being subjected to a tinnitus at a tinnitus frequency range including a tinnitus frequency is disclosed. The device includes an input transducer for providing an electric input signal comprising audio and a controllable filter for filtering the electric input signal received from the input transducer. The filter outputs a filtered electric input signal such that signal energy of the electric input signal immediately surrounding the tinnitus frequency remain substantially unchanged and signal energy of the electric input signal at a distance to the tinnitus frequency is substantially reduced. The device further includes a processor connected downstream of the filter and processes the filtered electrical input signal and outputs a processed electric signal, and an output transducer connected downstream of the processor and converts the processed electric signal to an acoustic output signal to be presented to a hearing impaired person.

A three-dimensional laser scanner instrument for acquiring three-dimensional geometric data of a scene (1) comprises an illumination system (3) for generating a light beam (2) and for scanning an illumination point of said light beam (2) through said scene (1), a light detection system (6-9) comprising at least one light detector (8), said light detection system being arranged to receive light from said scene (1), and an optical system (4) for imaging light scattered in or reflected from said scene (1) onto said light detection system (6-9). The light detection system (6-9) further comprises a controllable filter element (6) for dynamically discriminating light impinging from selected regions of said scene (1) and a control unit (9) operatively connected to said controllable filter element (6) and to said illumination system (3), wherein in operation of said scanner instrument, said filter element (6) is controlled by said control unit (9) so as to guide only light impinging from a selected, spatially delimited region around said illumination point in said scene (1) onto said at least one light detector (8).

The present invention relates to a method of filtering an input image for producing an output image. The method comprising the steps of, for a first image point located at first spatial coordinates:-analysing intensity levels of the input image in a first vicinity of the first image point for calculating a first direction of filtering at said first image point;-computing an intensity level of a first output image point of a first output image by applying a first steerable filter kernel to the input image, which is centered at the first image point and oriented along the calculated first direction of filtering; selecting at least a second image point in a second vicinity of said first image point in the first output image;-computing an intensity level of at least one second output image point of a second output image by applying at least a second steerable filter kernel to the input image, which is centered at the at least second image point and oriented along a second direction of filtering;-calculating a linear combination of the first output image point and of the at least second output image point for providing an output intensity level;-applying said output intensity level to an output image point of said output image, said output image point having said first spatial coordinates.

A frequency-control unit is used for controlling an external controllable reference-frequency source. The frequency-control unit includes a filter unit with a controllable filter parameter, which is configured to derive, using the filter parameter, from a frequency-error signal a frequency-control signal for minimizing the frequency error of the reference frequency; and a correlation unit, which is configured to determine from frequency errors of the reference frequency at different points in time a correlation measure indicative of a correlation between the frequency errors at the different points in time. The frequency-control unit is configured to adapt the controllable filter parameter of the filter unit in dependence on the determined correlation measure. The value of the filter parameter can depend also on a receiver path strength, such as an RSCP value.

An apparatus for calibrating an audio-visual (AV) signal includes a controller for generating a control signal, a controllable filter for selectively filtering the AV signal in response to the control signal to output either the AV signal or a filtered AV signal; and a calibrator for generating a group of calibrating coefficients according to the filtered AV signal and calibrating the AV signal according to the group of calibrating coefficients.

A method for downsampling fluoroscopic images and enhancing guidewire visibility during coronary angioplasty includes providing a first digitized image, filtering the image with one or more steerable filters of different angular orientations, assigning a weight W and orientation O for each pixel based on the filter response for each pixel, wherein each pixel weight is assigned to a function of a maximum filter response magnitude and the pixel orientation is calculated from the angle producing the maximum filter response if the magnitude is greater than zero, wherein guidewire pixels have a higher weight than non-guidewire pixels, and downsampling the orientation and weights to calculate a second image of half the resolution of the first image, wherein the downsampling accounts for the orientation and higher weight assigned to the guidewire pixels.