Abstract: Apparatus and a method for controlling the field or frame store signal processing of standard and nonstandard video signals is disclosed. The apparatus includes a nonstandard signal detector which compares the received horizontal sync signals to a horizontal sync signal generated internally be counting down a clock signal having a frequency proportional to the color subcarrier frequency. The detector produces a control signal which is in one state when the horizontal sync signals are substantially in coincidence and in a second state otherwise. This control signal is applied to apparatus which switches from field or frame store signal processing apparatus to alternative signal processing apparatus, which does not include a field or frame memory, to minimize distortion of the image when nonstandard signals are processed.

Abstract: Circuitry for detecting nonstandard video signals is disclosed. This circuitry is used in a sampled data video signal processing system to control signal processing steps which utilize a frame store memory. The detecting circuitry includes a programmable counter which generates a standard horizontal pulse signal having a 70 ns pulse width by counting down a sampling clock signal that has a frequency proportional to the color subcarrier frequency of the video signals. The circuitry generates another horizontal pulse signal having a pulse width of less than 140 ns from the horizontal sync pulses of the input video signals. These pulse signals are compared in a coincidence detector which produces a signal that is in a first state when the pulses of the two signals overlap at least once in every twenty-five horizontal line times and in a second state otherwise.

Abstract: A television apparatus for displaying the picture information of an interlaced signal, such as a baseband NTSC signal, in a non-interlaced scanning format is described. When no picture change occurs, the picture information of the first and the second fields of the NTSC signal are displayed in alternate scan lines of the display of the apparatus, respectively, to form a picture frame during one vertical scanning interval. A signal, indicative that a picture change occurs in a section of the picture frame, is generated when a picture change occurs. The picture change indicative signal causes the displayed picture information in that section of the picture frame to be derived from one field of the NTSC signal.

Abstract: Motion induced image distortion resulting from processing video signals in a frame-to-frame comb filter is substantially reduced by extracting motion induced luminance cross components in frame combed chrominance signal and reinserting them in the frame combed luminance signal. The chrominance signal is applied to a low pass filter to extract luminance components for reinsertion in the combed luminance signal. Higher frequency luminance cross components required to completely compensate the combed luninance signal are rejected by the low pass filter, however, to account for the missing high frequency luminance cross components, the combed luminance signal is selectively low pass filtered during interframe motion intervals before reinsertion of the cross components.