Abstract: This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for sensing touch and/or gestures in the near-field area overlying a light-guiding layer within a device or other optical sensing system. In one aspect, modulated infrared light is emitted into the overlying area, and the light reflected by objects within the overlying area is redirected through the light-guiding layer to infrared sensors. In one aspect, a masking structure can be located between the light-guiding layer and the infrared sensors. In some aspects, probability mapping or backtracing can be used to estimate the locations of objects within the overlying area.

Abstract: This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for sensing touch and/or gestures in the near-field area overlying a light-guiding layer within a device or other optical sensing system. In one aspect, modulated infrared light is emitted into the overlying area, and the light reflected by objects within the overlying area is redirected through the light-guiding layer to infrared sensors. In one aspect, a masking structure can be located between the light-guiding layer and the infrared sensors. In some aspects, probability mapping or backtracing can be used to estimate the locations of objects within the overlying area.

Abstract: A method of temporally adaptive filtering of the frames of an image sequence is disclosed. To filter the kth frame, first, the motion trajectories that transverse the pixel locations at the kth frame are determined using a motion estimation algorithm. Motion trajectories pass through a predetermined number of frames neighboring the kth frame. Image values at the neighboring frames, along motion trajectories are then evaluated. Temporally adaptive linear minimum mean square error (LMMSE) estimates of the image values at the pixel locations of the kth frame are determined using the image values along the motion trajectories. These steps are repeated for each of the other frames of the image sequence.

Abstract: A method for performing multiframe Wiener restoration of noisy and blurred image sequences that provides either a cross-correlated multiframe Wiener restoration or a motion-compensated multiframe Wiener restoration. The cross-correlated multiframe restoration uses interframe correlations explicitly through the estimated cross-power spectra of the frames, and is computationally efficient in its calculation of the Wiener estimate by using either a closed form solution or using a small-size matrix inversion. The motion-compensated multiframe Wiener restoration is used when the interframe motion is a global shift which is either known a priori, or estimated using a motion estimation algorithm. The motion-compensated multiframe Wiener filter has a closed-form solution and does not require any matrix inversion.

Abstract: In storage phosphor radiography, a portion of the x-ray energy transmitted through the subject is absorbed by a storage phosphor plate. When stimulated by visible light of the right wavelength, the phosphor plate emits light (at another wavelength) in proportion to the absorbed energy. To obtain the radiographic image, the plate can be scanned in a raster fashion and the emitted light can be photoelectrically detected. The detected signal is then amplified, digitized, processed and finally printed on film, or displayed on a cathode ray tube (CRT). Setting the amplification gain of this scanning process, the so-called final scan (or final read-out) gain, is of interest in maximizing the information extracted from the phosphor. One method of setting the final scan gain invokes the use of a preliminary read-out (pre-scan). A pre-scan can be conducted on the phosphor plate by use of a stimulating ray having a stimulating energy lower than the stimulating energy in the final scan.

Abstract: A phototimer for controlling x-ray exposure includes an array of x-ray sensors, and digital processing electronics for calculating x-ray exposure by selecting one or more signals from the x-ray sensors, and calculating the x-ray exposure from the selected signals. After calculating the x-ray exposure, the calculated exposure is employed to control the x-ray exposure either by displaying the calculated exposure to an operator who compares the calculated exposure with a desired exposure and repeats the exposure if necessary, or by automatically terminating the exposure by sending a control signal to the x-ray source. The improvement in the state of x-ray phototimer technology resides in the automatic selection of a subset of signals from a plurality of photosensors, thereby improving the reliability of the measurement. In prior art devices, the signals from a plurality of sensors were either selected manually by a switch, or all employed in a predetermined algorithm.

Abstract: In many digital image processing methods, it is desirable to selectively apply digital image processing to identifiable structures in the image. For this purpose it is known to select gray level thresholds between structures based upon the location of corresponding peaks in the gray level histogram of the digital image. However, it is a problem to automatically detect the locations of peaks in the histogram and to select the gray level thresholds. The present invention provides a method for automatically detecting the peaks and selecting gray level thresholds for segmenting a digital image into distinguishable structures including the steps of detecting peaks in a gray level histogram of the digital image by applying smoothing and differencing operators to the gray level histogram to generate a peak detection function wherein positive to negative zero crossings of the peak detection function represent the start of a peak, and maxima following such a zero crossing represents the end of a peak.