Video special effects generator

A video special effects generator for controlling the combining of video input signals into a video output signal under the control of horizontal and vertical synchronizing signals, said generator comprising:

• means for generating a series of first digital representations;
• means for storing one of said series of first digital representations;
• means operatively coupled to said first digital representation generating means and said storing means for comparing each of said series of first digital representations with said stored representation and rendering said storing means operative to store the last compared one of said series of first digital representations when the value of said last compared first digital representation differs from said stored first digital representation by a predetermined amount;
• means responsive to horizontal synchronizing signals for generating a second digital representation having a magnitude corresponding to the time elapsed since the most recent horizontal synchronizing signal;
• means responsive to vertical synchronizing signals for generating a third digital representation having a value corresponding to the time elapsed since the most recent vertical synchronizing signal;
• digital signal comparing means responsive to said digital representations for generating an output control signal having a state dependent upon the relative values of various ones of the digital signal representations applied thereto;
• video switching means for switching the video input signals into the video output signal under the control of the output signal generated by the digital signal comparing means;
• and
• means for altering the effect of various ones of said first, second and third signal representations on said output control signal to produce special effects controlled in accordance with said series of first digital representations.

A video special effects generator for controlling the combining of video input signals into a video output signal under the control of horizontal and vertical synchronizing signals, said generator comprising:

• means for generating a series of first digital representations;
• means responsive to horizontal synchronizing signals for generating a second digital representation having a value corresponding to the time elapsed since the most recent horizontal synchronizing signal;
• means responsive to vertical synchronizing signals for generating a third digital representation having a value corresponding to the time elapsed since the most recent vertical synchronizing signal;
• digital signal comparing means responsive to said digital representations for generating an output control signal having a state dependent upon the relative values of various ones of the digital signal representations applied thereto;
• means coupled to said comparing means for reversing the dependency of the state of said output control signal upon the relative values of the digital signal representations supplied to said signal inputs;
• video switching means for switching the video input signals into the video output signal under the control of the output control signal generated by the digital signal comparing means;
• and
• means for altering the effect of various ones of said first, second and third signal representations on said control signal to produce special effects controlled in accordance with the series of first digital representations.

A video special effects generator for controlling the combining of video input signals into a video output signal under the control of horizontal and vertical synchronizing signals said generator comprising:

• means for generating a series of first digital representations;
• means responsive to horizontal synchronizing signals for generating a second digital representation having a value corresponding to the time elapsed since the most recent horizontal synchronizing signal;
• means responsive to vertical synchronizing signals for generating a third digital representation having a value corresponding to the elapsed time since the most recent vertical synchronizing signal;
• digital signal comparing means responsive to said digital representations for generating an output control signal having a state dependent upon the relative values of various ones of the digital signal representations applied thereto;
• counting means for initiating a count in response to a change in the state of the output control signal from said digital comparing means, said counting means including means for providing an output signal representative of the time duration of said count;
• video switching means for switching one of the video input signals into the video output signal under the control of the output signal generated by said counting means;
• and
• means for altering the effect of various ones of said first, second and third signal representations on said control signal to produce special effects controlled in accordance with said series of first digital representations.

A video special effects generator for controlling the combining of video input signals into a video output signal under the control of horizontal and vertical synchronizing signals, said generator comprising:

• means for generating a first digital representation, said first digital representation generating means including means for generating a single binary digit;
• means responsive to horizontal synchronizing signals for generating a second digital representation having a value corresponding to the time elapsed since the most recent horizontal synchronizing signal;
• means responsive to vertical synchronizing signals for generating a third digital representation having a value corresponding to the time elapsed since the most recent vertical synchronizing signal;
• digital signal comparing means responsive to said digital representations for generating an output control signal having a state dependent upon the values of the second and third signal representations relative to the value represented by the single binary digit;
• and
• video switching means for switching the video input signals into the video output signal under the control of the output signal generated by the digital signal comparing means for generating a special effect controlled in accordance with said first digital representation.