Abstract: A synchronizing signal generator produces a PAL standard horizontal synchronizing signal using a PAL standard subcarrier signal as a timing reference. The synchronizing signal period is not an even multiple of the subcarrier signal period. To produce the synchronizing (sync) signal, the generator first frequency multiplies and divides the input signal to produce a reference signal having a period that is a rational multiple of the subcarrier signal period but smaller than the desired sync signal period. The generator then delays each successive pulse of the reference signal by increasingly longer delay times to produce the sync signal.

Abstract: A video converter converts an input video signal conveying pixel data representing an M.times.K pixel image to an output video signal conveying data representing an N.times.L pixel image. The converter samples the input video signal to acquire an M.times.K matrix of pixel data, re-encodes each pixel data value as necessary to meet color coding requirements of the output video signal standard, and then employs digital interpolation and/or decimation filters to convert the M.times.K data matrix to an N.times.L data matrix. A simple digital output encoder operating at four times the output video signal subcarrier frequency is then employed to process the N.times.L matrix to produce a digital output data sequence which, when applied to D/A converter, becomes the output video signal.

Abstract: A bilinear decimator converts an input data sequence representing a high resolution image formed by N horizontal pixel lines to an output data sequence representing a lower resolution image formed by P horizontal pixel lines where N>P. The decimation ratio P/N can be any rational fraction. When the decimation ratio reduces to the form 1-(1/n), the decimator computes the each output sequence data value as a simple weighted average of pixel data values for two vertically adjacent high resolution image pixels. When the decimation ratio is other than of the form 1-(1/n), the decimator adds additional terms to the computation of output pixel data values when necessary to compensate for aliasing errors.