Abstract: Block matching for picture motion estimation uses offset quantized pixel values. The pixels of a reference block from a first frame of a video picture sequence are offset quantized to produce a pair of offset quantized reference pixel signals. The pixels of a search area from a next frame of the video picture sequence, corresponding to a current position of the reference block relative to the search area, the search area being larger than the reference block, are quantized to produce a quantized search pixel signal. The quantized search pixel signal is compared with each of the offset quantized reference pixel signals on a pixel by pixel basis to determine whether absolute equality exists between the respective pairs of pixel signals. The comparison results are combined so that for each quantized pixel of the search block that has absolute equality with either offset quantized reference pixel signal, a tally count is incremented.

Abstract: A FIR filter based upon squaring accumulates the sum of the squares of the samples of a digital input signal. The samples also are added to respective filter coefficients, squared and accumulated in a plurality of filter stages. The sum of the squares of the samples are subtracted, together with a constant that is the sum of the squares of the filter coefficients, from the output of the last filter stage to produce an output signal that is divided by two to produce the samples for a digital output signal.

Abstract: Composite video timing adjustments using digital resampling provides precise sub-pixel timing relative to a timing reference with a single video master clock. A digital resampler interpolates an input digital composite video signal as a function of a phase offset input which defines a fractional clock period of the video master clock derived from the timing reference. The sub-pixel offset digital composite video signal also may be adjusted by integer multiples of the video master clock period using a FIFO memory. The final timing adjusted digital composite video signal then is input to an analog reconstruction circuit to provide an output analog composite video signal that is precisely timed to the timing reference.

Abstract: A method for locking scales to a waveform display uses reference points from the waveform to determine starting scale points. Based upon the starting scale points and the characteristics of the waveform the scales are calculated. Any changes in gain in the waveform are applied to the scales so that the scales change in direct proportion to the waveform. The field/line numbers of a television video signal are tracked and displayed on the waveform display to identify that portion of the waveform relative to a picture frame which is being displayed.

Abstract: A method for positioning cursors at a specific point on a displayed waveform uses a cursor to determine the maximum and minimum points on the waveform about a transition portion. For each position of the cursor between the maximum and minimum points an intersection between the cursor and the waveform is computed as a percentage of the difference between the maximum and minimum points. The cursor is then positioned at a point on the transition portion where the percentage is a desired value for the specific point.

Abstract: A method for automatically finding color bars within a television video signal checks for a black burst at the end of a horizontal video line to determine the appropriate color bar standard for testing. Then a reference color burst, such as the yellow color burst, is searched for in the appropriate location within the horizontal line. Related color burst locations are demodulated to produce related color angles which are checked for relationship with the reference color burst. Also the luminance amplitudes for each color burst are compared to each other to determine whether a correct amplitude relationship is present. Each horizontal line of a picture frame is tested until either the color bars are found or all the horizontal lines have been tested. The found color bars are displayed in an appropriate format together with the line number within the picture frame, or a message indicating no color bars is displayed.

Abstract: Touch controlled zoom of a waveform display uses a touch screen for the display surface. Function buttons for moving or expanding the waveform display and for determining the axis of such movement or expansion operate in conjunction with a rotary encoder. Expansion, or zoom, is accomplished by contacting the screen overlying a point on the waveform about which zoom is desired. Such contact or activation of the expand function button results in movement of the rotary encoder providing a gain parameter to a zoom function. The zoom function operates on the waveform display in an exponential manner as a function of the gain parameter to expand or contract the waveform display about the zoom point according to the direction of rotation of the rotary encoder.

Abstract: A cursor interface for a waveform display provides for movement of a waveform relative to a first cursor. When the first cursor overlies a desired point on the waveform, the cursor is locked to the waveform by transforming the cursor coordinates from display coordinates to waveform coordinates. The waveform may then be moved together with the first cursor relative to a second cursor. When the second cursor overlies another desired point on the waveform, a measurement value is displayed indicating the difference in positions on the waveform of the cursors. The cursors may be centered independently, and when locked to the waveform the result is to correspondingly move the waveform.

Abstract: A method for correlating video data between two video display formats uses a multi-function instrument which digitizes the input video data. An operator selects a horizontal line of the video data via a rotary encoder which updates a global variable common to all display formats. Subsequent selection of a different display format results in the same horizontal line of the video data being displayed in the new display format.