Video signal processing apparatus

• US 4,855,831 A
• Filed: 10/29/1987
• Issued: 08/08/1989
• Est. Priority Date: 10/31/1986
• Status: Expired due to Term

• Current Assignee: Victor Company of Japan Limited 3-12 Moriya-Cho Kanagawa-Ku
• Original Assignee: Victor Company of Japan Limited (JVC Kenwood Corporation)
• Inventors: Kato, Daisaku, Miyamoto, Fumitaka
• Primary Examiner(s): Britton, Howard W.
• Assistant Examiner(s): Peng, John K.
• Application Number:
  US07/115,604
• Time in Patent Office: 649 Days
• Field of Search: 358/182, 358/183, 358/22, 340/721
• US Class Current: 348/597
• CPC Class Codes: H04N 5/2622 Signal amplitude transition in the zone between image portions, e.g. soft edges

Abstract

A superimposing video signal represents a superimposing shape. The superimposing video signal and a background video signal are mixed at a varible mixing rate. During an interval where the superimposing video signal corresponds to an edge of the superimposing shape, the mixing rate is varied. The superimposing video signal may be stored in a memory. The mixing rate may be varied in accordance with a mixing rate signal stored in a memory.

Claims

1. A video signal processing apparatus comprising:

(a) means for generating a superimposing video signal representing a superimposing image;

(b) means for mixing the superimposing video signal and a background video signal at a variable mixing rate; and

(c) means for varying the mixing rate during an interval where the superimposing video signal corresponds to an edge of the superimposing image,

further comprising means for selecting either of the superimposing video signal and an output signal from the mixing means which represents a mixture of the superimposing video signal and the background video signal.

2. A video signal processing apparatus comprising:

(a) means for generating a superimposing video signal representing a superimposing image;

(b) means for mixing the superimposing video signal and a background video signal at a variable mixing rate; and

(c) means for varying the mixing rate during an interval where the superimposing video signal corresponds to an edge of the superimposing image,

further comprising a switch selecting either of the superimposing video signal and an output signal from the means for mixing which represents a mixture of the superimposing video signal and the background video signal.

3. A video signal processing apparatus comprising:

(a) means for generating a superimposing video signal representing a superimposing image;

(b) means for mixing the superimposing video signal and a background video signal at a variable mixing rate; and

(c) means for varying the mixing rate during an interval where the superimposing video signal corresponds to an edge of the superimposing image,

wherein said means for mixing comprises first input means for receiving said superimposing video signal representing a superimposing image, second input means for receiving said background video signal, output means for providing an output mixed signal comprising a mix of said superimposing video signal and said background video signal at a predetermined mixing ratio, and control input means for receiving a control signal to establish said predetermined mixing ratio,

wherein said means for varying the mixing rate comprises means for generating said control signal as a varying signal to vary said predetermined mixing ratio

further comprising switch means for selecting either of the superimposing video signal and an output signal from the means for mixing which represents a mixture of the superimposing video signal and the background video signal.

4. The apparatus of claim 3, further comprising comprises memory means for storing mixing enable signals for enabling said switch means to select said output signal from the mixer representing mixture of the superimposing video signal and the background video signal to provide to a display means, and address means for addressing said memory means to output said mixing enable signals to said switch means for each display element of said background video signal.

5. A video signal processing apparatus comprising:

(a) means for generating a digital superimposing video signal representing a superimposing image;

(b) digital-to-analog converting means for converting the digital superimposing video signal into a corresponding analog superimposing video signal;

(c) an analog signal mixer means for mixing the analog superimposing video signal and an analog background video signal at a variable mixing rate; and

(d) means for varying the mixing rate during an interval where the superimposing video signal corresponds to an edge of the superimposing image.

6. A video signal processing apparatus comprising:

(a) a first memory;

(b) means for storing a digital superimposing video signal into the first memory, the digital superimposing video signal representing a superimposing shape;

(c) a first digital-to-analog converter;

(d) means for supplying the digital superimposing video signal form the first memory to the first digital-to-analog converter, wherein the first digital-to-analog converter converts the digital superimposing video signal into a corresponding analog superimposing video signal;

(e) a second memory;

(f) means for storing a digital mixing rate signal into the second memory, the digital mixing rate signal representing mixing rates predetermined for respective segments of the superimposing shape, the mixing rates varying in a range corresponding to an edge of the superimposing shape;

(g) a second digital-to-analog converter;

(h) means for supplying the digital mixing rate signal to the second digital-to-analog converter, wherein the second digital-to-analog converter converts the digital mixing rate signal into a corresponding analog mixing rate signal;

(i) an analog signal mixer;

(j) means for supplying the analog superimposing video signal from the first digital-top-analog converter to the analog signal mixer;

(k) means for supplying the analog mixing rate signal from the second digital-to-analog converter to the analog signal mixer; and

(1) means for supplying an analog background video signal to the analog signal mixer;

wherein the analog signal mixer mixes the analog superimposing video signal and the analog background video signal at a mixing rate represented by the analog mixing rate signal.