Maximum Pixel

Abstract: A Time-Of-Flight (TOF) range image sensor using current assisted photonic mixing demodulator is presented. The demodulator structure, featuring a remarkably small pixel size (10 × 10 µm2), is used to realize a 160 × 120 pixel array of ranging sensor fabricated in standard 0.18 µm CMOS technology. The third dimension, i.e. depth information, can be determined by correlating the reflected modulated light signal from the scene with a reference signal synchronous with the light source modulation signal. Initial results demonstrate that the demodulator structure is suitable for a real-time 3D image sensor. A good charge separation efficiency and demodulation capabilities are achieved up to modulation frequencies larger than 20 MHz. The impact of important parameters such as wavelength, modulation frequency and voltage on this test device are also experimentally evaluated. The prototype camera system is capable of providing real-time distance measurements of a scene through modulated-wave TOF measurements with a modulation frequency of 20 MHz. In the distance measurement, the sensor array provides a linear distance range from 1.2m to 3.7m with maximum accuracy error 3.3% and maximum pixel noise 8.5% at 3.7m distance.

Abstract: This paper discusses image decomposition problem of the 3-layer MRC model based coding of scanned (noisy) document images. A widely-used approach for document decomposition is to divide the document image into blocks and split the pixel histogram of each block into two halves by minimizing the sum of variance of its pixels with the mean of the halves. We propose to split a block by minimizing the variance of one half with its minimum pixel and the variance of the other half with its maximum pixel. Our goal is to increase the gap between the two halves by avoiding splitting of any cluster of pixels into both halves. It should help reduce complexity of the generated mask. Moreover, we do not decompose a block if it has no edge points, again to reduce the mask complexity. We also implement a noise reduction heuristic in the mask layer to correct placement of transition pixels. We provide simple analysis and evaluate block energy in terms of the DCT coefficients of the resulting FG/BG layer blocks. Experimental results show that code size of the mask layer of our test images, obtained using proposed processing is reduced to nearly half of the mask obtained by a straight-forward 3-MRC implementation.

Abstract: The present invention relates to a method for detecting a defect on a substrate and, more particularly, to a method for detecting a defect on a substrate which is used as panel glass of a display device The provided method for detecting a defect on a substrate comprises as follows: a pixel value obtaining step which obtains a pixel value of a substrate image by performing line scan on the substrate; a flattening step which flattens the obtained pixel value; and a detecting step which detects a defect on the substrate by comparing the flattened pixel value with a threshold The flattening step is conducted by the following formula: Here, P(x, y) is a pixel value at coordinate (x, y), m(x) = a mode (h_x(k)), h(k) is a histogram of the entire obtained pixel values, h_x(k) is a histogram of the pixel value at coordinate x, and I is the maximum pixel value which can be obtained by a line-scan camera

Abstract: A three-dimensional image of flowing fluid or moving tissue using velocity or power Doppler data is displayed by using an ultrasound scanner that collects velocity or power data in a cine memory to form a volume of pixel data. Average or median pixel values are projected (86) on an image plane by casting rays through the data volume. As the ray passes through each scan plane, a data value is assigned to the ray at that point. At each scan plane, the assigned pixel data value is tested (88) to see if it exceeds a noise threshold. For a given ray, pixel data values above the detection threshold are accumulated (90) until a pixel data value falls below the detection threshold (92). A minimum number of pixel data values exceeding the threshold are required for each ray before the average of the accumulated values is processed and/or the median value is selected (94). When all pixels along a given ray have been tested, the projection is complete and the average or median projection is then displayed. Uniformity within the projected image and the sharpness of edges are enhanced by projecting average or median pixel values instead of maximum pixel values.