.[.A method.]. .Iadd.An apparatus and system .Iaddend.for producing a digital video signal from an analog video signal, the analog video signal including an analog video data signal that is raster scanned in lines across a CRT screen to form consecutive frames of video information, the raster scanning controlled by use of a horizontal synchronizing signal .[.(H.sub.snyc).]. .Iadd.(H.sub.sync) .Iaddend.that controls a line scan rate, and a vertical synchronizing signal .[.(V.sub.snyc).]. .Iadd.(V.sub.sync) .Iaddend.that controls a frame refresh rate, to produce consecutive frames of video information, wherein the digital signal is produced by generating a pixel clock signal with pixel clocks for repetitively sampling instantaneous values of the analog video data signal, and digitizing the analog video data signal based on the pixel clock sampling. An expected width E, measured in number of pixel clocks, of a video image producible by the analog video signal is estimated, and an actual width W, measured in number of pixel clocks, of the video image producible by the analog video signal is calculated. The actual width W is compared with the expected width E. When E does not equal W, at least one of a frequency component and a phase component of the pixel clock signal is adjusted until E equals W.