Apparatus and methods for synthesizing foreground and background images
AssigneeNuWave Technologies, Inc.
InventorRobert I. Webb
Life of this patent
Estimating the term…
Abstract
An apparatus and method for improving the clarity of a picture produced from a video signal. A differentiation circuit is provided that produces a responsive correction signal. Mechanisms for adjusting the shape (width, amplitude, etc.) of the correction signal are disclosed. Disabling the correction signal during blanking intervals and synchronization is also disclosed, among other features.
Claims43
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- an analog differentiation circuit having a singular analog differentiator that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- a filter that modifies the shape of the correction signal;
- and
- a mechanism that combines the modified correction signal to the luminance signal at the corresponding transition thereof.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates an analog correction signal in response to a transition of that luminance signal;
- a filter that modifies the shape of the analog correction signal;
- and
- a mechanism that combines the modified analog correction signal to the luminance signal at the corresponding transition thereof;
- wherein said differentiation circuit and said filter are powered by a single ended power supply having a magnitude of substantially 5V or less.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- a mechanism that combines the correction signal to the input luminance signal;
- and
- a mechanism for that disables the correction signal during a blanking interval of the input luminance signal.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- a mechanism that modifies the amplitude of the correction signal;
- and
- a mechanism that combines the amplitude modified correction signal to the luminance signal at the corresponding transition of that luminance signal;
- and
- wherein the amount of amplitude modification is user selectable.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates an analog correction pulse in response to a transition of that luminance signal;
- and
- a mechanism that combines the analog correction pulse to the input luminance signal at the corresponding transition of that luminance signal;
- wherein the differentiation circuit includes a capacitor and a resistor that create a differentiation circuit time constant that has a value of less than 180 ns.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction pulse in response to a transition of that luminance signal;
- a pulse width extension circuit that functions only to extend the width of said correction pulse;
- and
- a mechanism that combines the width extended correction pulse to an input luminance signal at the corresponding transition.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- and
- a mechanism that combines the correction signal to the input luminance signal;
- wherein the differentiation circuit includes a capacitive element and a resistive element that create a time constant for said correction signal of less than substantially 60 ns.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- a filter that modifies the shape of the correction signal;
- and
- a mechanism that combines the modified correction signal to the luminance signal at the corresponding transition thereof;
- wherein the amount of said modification is user selectable.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- a filter that modifies the shape of the correction signal;
- a mechanism that combines the modified correction signal to the luminance signal at the corresponding transition thereof;
- and
- an isolation buffer coupled between said differentiation circuit and said filter.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives an input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- and
- a filter that modifies the shape of the correction signal;
- a mechanism that combines the modified correction signal to the luminance signal at the corresponding transition thereof;
- and
- a constant current source coupled between said differentiation circuit and said filter.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- and
- a filter that modifies the shape of the correction signal;
- a mechanism that combines the modified correction signal to the luminance signal at the corresponding transition thereof;
- and
- a mechanism that disables the correction signal during a blanking interval of the input luminance signal.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- a filter that modifies the shape of the correction signal;
- and
- a mechanism that combines the modified correction signal to the luminance signal at the corresponding transition thereof;
- wherein said apparatus is fabricated in metal-oxide-semiconductor (MOS) material.
An apparatus for improving apparent clarity of a picture produced from a video signal, comprising:
- a differentiation circuit that receives as input a luminance signal and that creates a correction signal in response to a transition of that luminance signal;
- a modification circuit that modifies the shape of the correction signal;
- and
- a mechanism that combines the modified correction signal to the luminance signal at the corresponding transition thereof;
- and
- wherein said differentiation circuit has a differentiation circuit time constant defined at least in part by a capacitor having a value of less than 50 pF.
Dependencies are inferred from the claim text.