Abstract: A luminance qualified vector display device provides a vector display that is gated by a specified luminance range. In one implementation three luminance gates may be used, one for luminance levels above a specified high luminance threshold, a second for luminance levels below a specified low luminance threshold, and a third for luminance levels between the specified high and low luminance thresholds. Also the luminance thresholds for the medium luminance range may be separately adjusted to overlap the high and low luminance ranges respectively. Each luminance qualified vector display may be displayed separately, may be overlaid for display using a different color for each luminance range, or may be displayed in different quadrants of a display device or window together with the normal, non-luminance qualified, vector display.

Abstract: An apparatus and method for controlling and detecting the alignment of a color frame phase from a composite analog video signal decodes the composite analog video signal to produce a component digital video signal and to generate a color frame signal that represents the start of each color frame for the composite analog video signal. Based upon the color frame signal a flag signal is inserted into the component digital video signal. The component digital video signal is captured by an analyzer based upon the flag signal so that the captured component digital video signal is in color frame phase with a stored reference component digital video signal. Preferably the stored reference component digital video signal represents a test sequence having an integer number of color frames plus or minus one video frame.

Abstract: Alignment of two video sequences, one being a reference video sequence and the other being a processed video sequence corresponding to the reference video sequence, is performed using selected partial pictures from the reference video sequence. The reference video sequence is evaluated for portions that have maximum information content spatially and/or temporally to select the partial pictures, and the location and size of the partial pictures are stored together with the reference video sequence. The processed video sequence is then initially aligned to the reference video sequence by first finding the locations of features from the partial pictures in the processed video sequence to provide a coarse misalignment error between the two video sequence, and then using a correlation algorithm with a scanning window based on the size of the partial pictures to refine the misalignment error.

Abstract: A three-dimensional test signal for a video codec is generated by injecting a conventional foreground test signal at a predetermined location as a foreground component within a background test signal as a background component, the background component having a variable complexity. The three-dimensional test signal is input to the video codec and the output of the video codec is measured using conventional measurement instruments. The background component may be a pseudo-random noise signal, a zone plate signal or other variable complexity-type signal, with the foreground component occurring at greater intervals than the neighboring pixels used by the codec compression algorithm. The conventional measurement instruments display only the foreground component with distortions in the video codec caused by the complexity of the background component appearing in the display.

Abstract: An edge integrating phase detector for a phase locked loop passes a portion of a sync edge of an input video signal as a sampled signal to an integrator in response to a gate pulse nominally centered on a timing reference point of the sync edge. The sampled signal has a positive and negative portion. The integrator produces from the sampled signal a control signal for a VCO that is proportional to the unbalance between the positive and negative portions. The gate pulse is generated from the output of the VCO as a function of the nominal period of the input video signal.

Abstract: A method for examining a propagative medium, such as a signal transmission cable, that requires the acquisition and examination of a minimum number of data points to determine the presence of an anomaly in the medium. When an anomaly is detected, its characteristics, such as loation, type and amount of loss are determined. The characteristics are then displayed. If the anomaly is a reflectionless loss, the region containing the anomaly is examined repetitively to determine its location and to improve the accuracy of its location measurement. With each successive level of examination, additional samples are collected within the region. The new samples are combined with the existing samples to reduce random noise in the data. Through this method the location of the anomaly is re-determined with greater accuracy.

Abstract: An input signal is sampled by alternately coupling the input signal and a reference level to a sample storage element, whereby the magnitude of the signal stored by the storage element immediately following application of the input signal to the storage element is a function of the input signal magnitude and the magnitude of the signal stored by the storage element immediately preceding coupling of the input signal to the storage element is a function of the reference level.