Abstract: An apparatus for correcting errors in color signal transitions includes a signal scaling device and a signal mixing device. A wide bandwidth luminance signal is applied to the signal scaling device which develops a limiting signal for a particular narrow bandwidth color difference or primary color signal. This limiting signal is mixed with its associated color difference or primary color signal by the signal mixing device. The output of the signal mixing device is a color difference or primary color signal that has amplitude values less than or equal to the amplitude values of the limit signal.

Abstract: Hue and saturation are modified in a composite video signal processor by detecting the phase of the chrominance signal component to determine if it possesses phase components at or near a predetermined phase angle. If such components exist, quadrature related saturation and hue modifying signals are added to the composite video signal in controlled proportions and polarities to provide a resultant composite video signal in which a specified color or range of colors is modified. The modifying signals are inhibited by a masking unit to confine the color modification to predetermined areas of the displayed color image. Specific picture locations where color changes occur are identified by substituting an AC signal within the luminance frequency band for the color modifying signals. A desaturation signal derived from the hue modifying signals is added to the composite video signal to minimize changes in saturation level of the composite video signal as hue is changed.

Abstract: A synchronizer receives from a tape playback arrangement television frames at a rate which is slightly higher or slightly lower than a standard frame-rate. The synchronizer includes four frames of storage, and reading and writing are continuous. In a mode in which the incoming frame rate is high, the read and write become separated in time as time passes due to the difference in frame rate. When reading and writing are separated by at least two frames, a motion detector is activated to continuously interrogate the memory in order to locate two identical frames. When two frames are identified as being identical, the read address is immediately switched by two fields, thereby bypassing or dropping two fields. This drop is not visible because the motion detector has identified the fields as being substantially identical.

Abstract: A video disc player includes a phase locked loop (PLL) heterodyne converter for providing frequency translation and time base correction of the chrominance component of a composite video signal recovered when a disc is played. Residual time base errors due to the finite loop gain of the PLL are minimized by means of a phase modulator controlled by the PLL error signal. In one illustrative embodiment, the phase modulator is coupled so as to vary the phase of the translated chrominance output signal. In another embodiment, it is coupled to vary the phase of a demodulation carrier wave supplied to a chroma demodulator whereby, in either case, chroma streaking effects due to finite gain limitations of the PLL are minimized with no increase in loop gain thereby avoiding potential loop instabilities.

Abstract: A circuit providing independent control of selected color areas, such as fleshtone areas, is shown. The circuit comprises a fleshtone detector and a fleshtone contour control circuit. The fleshtone detector comprises a negative absolute value circuit using PNP transistors. A delay line circuit can be used to expand the fleshtone contour level to areas beyond the fleshtone areas. A fleshtone detector can also be used to control other special effects, such as luminance.

Abstract: A signal indicative of tape tension or of recording of signal on tape is generated in a helical-scan recorder. A test signal having a particular frequency characteristic is recorded by rotating heads at a high head-to-tape speed. A fixed playback head downstream from the headwheel picks up the test signal converted in frequency by the ratio of the reading speed to the writing speed, and applies it to a detector. The detector is a synchronous detector which receives at a second input terminal a frequency-divided sample of the test signal which controls demodulation by the synchronous detector. The frequencies of the input signals to the phase detector differ by a small amount, so that an output signal can always be generated no matter what the phase of the input signal. The rate of pulsation of the output signal is indicative of tape tension.

Abstract: Apparatus for controlling the playback speed of a VTR features an accurate speed control signal. The reproduced signal is resynchronized to a standard speed by repeating or deleting frames when successive frames are substantially identical. In addition, or as an alternative, frame averaging can be used. Provision for real time entry is made to minimize human error. Application of the invention to both quadruplex and helical scan machines is shown.

Abstract: The size of a color television picture field is changed without changing the size of the raster. This is achieved in an apparatus that includes means responsive to a field of television video signals for sampling same and providing a predetermined number of samples of television video signals per line and a predetermined number of lines per field and means responsive to the predetermined number of samples per line and lines per field for providing a full field of television video signals. Size reduction is accomplished by causing the first mentioned means to skip samples provided at the output thereof in groups of N, where N is the number of samples in a color subcarrier cycle, and to skip line pairs of the field.

Abstract: A time base corrector for removing time base errors from video signal information of a type including synchronizing pulses is provided. A storage means in the form of a charge coupled device (CCD) has the video information coupled to its input. A start-stop oscillator in conjunction with a preset counter coupled to the storage means clocks the video information into the storage means so as to stop the clock when the input signal information has been transferred to the output terminal of the storage means. A local reference restarts the clock and the stored input signal information is clocked out in synchronism with the local reference.