APPARATUS FOR PREVENTING BUFFER OVERFLOW IN VIDEO ENCODING SYSTEMS BY INCREASING THE SCANNING RATE OF A CAMERA DURING THE TIME INTERVAL OF THE ENCODING OF DIGITAL WORDS OF EXTRA LENGTH

摘要

To prevent buffer overflow from line-to-line accumulation of information in video encoding systems, a detector circuit notes the occurrence of extra words or extra digits produced by a variable word length encoder. In response to this detection, a voltage adding means incrementally alters the slope of the horizontal sweep sawtooth which, in turn, results in a temporary increase in camera scanning speed. Logic means insures that the time obtained from the active scanning region by increasing scanning speed is allocated to the blanking interval.