Picture adjusting method of a color television and its circuit

• US 5,488,434 A
• Filed: 05/14/1992
• Issued: 01/30/1996
• Est. Priority Date: 05/16/1991
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Jung, Tae-Hong
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): Metjahic, Safet
• Application Number:
  US07/882,864
• Time in Patent Office: 1,356 Days
• Field of Search: 358/161, 358/168, 358/169, 358/27, 358/28, 358/56, 358/64, 358/188, 358/242, 358/83, 358/160, 358/21 R, 358/194.1
• US Class Current: 348/725
• CPC Class Codes: H04N 5/44 Receiver circuitry for the reception of television signals according to analogue transmission standards H04N5/14 takes precedence
• CPC Class Codes: H04N 5/58 in dependence upon ambient light

Abstract

The present invention relates to a picture adjusting method of a color television and its circuit for obtaining enhanced picture resolution by automatically adjusting the contrast, a brightness and sharpness of a picture in accordance with the ambient brightness, picture brightness, magnitude of RF signals and viewing distances of a remote controller from a television screen, utilizing either a set of fuzzy logic rules with fuzzy logic reasoning, or a look-up table having data corresponding to the detected ambient brightness, picture brightness, magnitude of the RF signals and the viewing distances of the remote controller from the television screen.

Claims

1. A picture adjusting method of a color television, comprising:

a first process for generating addresses in dependence upon information data respectively representative of an ambient brightness in an environment surrounding said color television, a picture brightness, an instantaneous magnitude of video signals representative of a visual display on a screen of said color television and a viewing distance between a viewer and said color television by determining whether the information data respectively representative of the ambient brightness, the picture brightness, the instantaneous magnitude of the video signals and the viewing distance is input, and reading the information data when the information data is input; and

a second process for adjusting contrast, brightness and sharpness of the visual display on said screen of the color television by reading corresponding data from a look-up table comprising a plurality of fuzzy inference rules and membership functions defining different levels of contrast, brightness and sharpness of the visual display according to the addresses generated from said first process, determining adjusted values respectively representative of the contrast, the brightness and the sharpness of the visual display on the screen according to the information data, and adjusting the contrast, the brightness and the sharpness of the visual display on the screen according to the adjusted values.

2. The picture adjusting circuit as claimed in claim 1, further comprised of said membership functions defining the ambient brightness as being one of dark, slightly dark, slightly bright and bright, the picture brightness as being one of dark, slightly dark, medium dark, slightly bright and bright, the magnitude of said video signals as being one of weak, slightly weak, slight strong and strong, and the viewing distance as being one of near, medium and far from the color television, and said fuzzy inference rules controlling the contrast, brightness and sharpness of the image in dependence upon said membership functions.

3. A picture adjusting circuit of a color television, comprising:

sensing means for generating sensed signals by sensing an ambient brightness in an environment surrounding the color television, a picture brightness and a magnitude of video signals representative of an image on a display screen;

data converting means for converting the sensed signals respectively representative of the ambient brightness, the picture brightness and the magnitude of said video signals into digital signals respectively representative of said ambient brightness, said picture brightness and the magnitude of said video signals;

remocon receiving means for receiving a remote control signal from a remote controller, and for generating a distance detected signal upon a detection of a viewing distance between said remote controller and said color television in dependence upon said remote control signal;

membership function storing means having a plurality of membership functions, for providing discriminated signals by discriminating amplitude levels of the distance detected signal and the digital signals respectively representative of the ambient brightness, the picture brightness and the magnitude of said video signals in dependence upon said plurality of membership functions;

fuzzy rule storing means having a look-up table of a plurality of fuzzy rules for controlling contrast, brightness and sharpness of the discriminated signals respectively representative of the ambient brightness, the picture brightness, the magnitude of said video signals and the viewing distance;

fuzzy logic means for determining adjusted values respectively representative of the contrast, the brightness and the sharpness according to the digital signals representative of the ambient brightness, the picture brightness, the magnitude of said video signals and the viewing distance; and

image signal treatment means for performing the adjustment of the contrast, the brightness and the sharpness of the image on the display screen according to said adjusted values.

4. The picture adjusting circuit of a color television according to claim 3, wherein said sensing means comprises:

a first sensor consisting essentially of a photo-resistor, for detecting the ambient brightness in the environment surrounding said color television;

a second sensor coupled to receive an output voltage of an automatic brightness limiter, for detecting the picture brightness of said image on the color television; and

a third sensor coupled to receive said video signals from a tuner, for detecting the amplitude of said video signals.

5. The picture adjusting circuit of a color television according to claim 4, wherein said second sensor comprises:

an input terminal coupled to receive the output voltage of the automatic brightness limiter;

an output terminal for providing the picture brightness;

a first resistor interposed between said input terminal and a power source;

a second resistor interposed between said input terminal and said output terminal; and

a third resistor interposed between said second resistor and ground.

6. The picture adjusting circuit of a color television according to claim 4, wherein said third sensor comprises:

an input terminal coupled to receive the video signals;

an output terminal for providing the amplitude of said video signals;

a first resistor interposed between said input terminal and said output terminal; and

a second resistor interposed between said input terminal and ground.

7. The picture adjusting circuit as claimed in claim 3, wherein said ambient brightness is defined by said membership functions as an input status of one of dark, slightly dark, slightly bright and bright, said picture brightness is defined by said membership function as input status of one of dark, slightly dark, medium dark, slightly bright and bright, said magnitude of said video signals is defined by said membership functions as input status of one of weak, slightly weak, slight strong and strong, and said viewing distance is defined by said membership functions as input status of one of near, medium and far from the color television, for respectively controlling the contrast, brightness and sharpness of the image in dependence upon the input status of each of said ambient brightness, said picture brightness, said magnitude of said video signals and said viewing distance of the remote controller from the color television.

8. A picture adjusting circuit of a color television, comprising:

means for receiving video signals representative of an image on said color television;

sensing means for generating sensed signals by sensing an ambient brightness in an environment surrounding the color television, a picture brightness and a magnitude of said video signals;

data converting means for converting the sensed signals respectively representative of the ambient brightness, the picture brightness and the magnitude of said video signals into digital signals respectively representative of the ambient brightness, the picture brightness and the magnitudes of said video signals;

remocon receiving means for generating a distance detected signal in dependence upon a detection of a viewing distance between a viewer and said color television;

processor means comprising a plurality of fuzzy inference rules and membership functions representative of different levels of contrast, brightness and sharpness of said image, for determining adjusted values respectively representative of the contrast, the brightness and the sharpness of the image on the display screen based on said fuzzy inference rules and said membership functions in dependence upon reception of the distance detected signal and the digital signals respectively representative of the ambient brightness, the picture brightness and the magnitude of said video signals; and

image signal treatment means for performing the adjustment of the contrast, the brightness and the sharpness of the image on the color television according to the adjusted values.

9. The picture adjusting circuit of a color television according to claim 8, wherein said sensing means comprises:

a first sensor consisting essentially of a photo-resistor, for detecting the ambient brightness;

a second sensor coupled to receive an output voltage of an automatic brightness limiter, for detecting the picture brightness; and

a third sensor coupled to receive said video signals from a tuner, for detecting the amplitude of said video signals.

10. The picture adjusting circuit of a color television according to claim 9, wherein said second sensor comprises:

an input terminal coupled to receive the output voltage of the automatic brightness limiter;

an output terminal for providing the picture brightness;

.

a first resistor interposed between said input terminal and a power source;

a second resistor interposed between said input terminal and said output terminal; and

a third resistor interposed between said second resistor and ground.

11. The picture adjusting circuit of a color television according to claim 9, wherein said third sensor comprises:

an input terminal coupled to receive the video signals;

an output terminal for providing the amplitude of said video signals;

a first resistor interposed between said input terminal and said output terminal; and

a second resistor interposed between said input terminal and ground.

12. A picture adjusting circuit, comprising:

means for generating a first signal corresponding to instantaneous magnitude of a video signal representative of an image for a visual display, for generating a second signal representative of brightness of the image for said visual display, and for generating a third signal representative of ambient light in an environment surrounding said visual display;

means for receiving remote control signals from a remote controller for regulating said visual display, and for generating a fourth signal representative of a distance between said visual display and said remote controller in dependence upon said remote control signals;

means for adjusting contrast, brightness and sharpness of the image for said visual display in dependence upon said first, second, third and said fourth signals, said contrast, brightness and sharpness adjusting means comprises;

membership function storing means having a plurality of membership functions, for discriminating amplitudes of said first, second, third and fourth signals in dependence upon said plurality of membership functions to respectively provide first, second, third and fourth discriminated signals;

fuzzy rule storing means having a look-up table of a plurality of fuzzy inference rules for controlling contrast, brightness and sharpness of the image for said visual display in dependence upon said first, second, third and fourth discriminated signals;

fuzzy logic means for determining adjusted values respectively representative of the contrast, the brightness and the sharpness of the image for said visual display in dependence upon said first, second, third and fourth discriminated signals; and

image signal treatment means for performing the adjustment of the contrast, the brightness and the sharpness of the image for said visual display according to said adjusted values.

13. The picture adjusting circuit according to claim 12, further comprised of said membership functions defining the ambient brightness as being one of dark, slightly dark, slightly bright and bright, the picture brightness as being one of dark, slightly dark, medium dark, slightly bright and bright, the magnitude of said video signals as being one of weak, slightly weak, slight strong and strong, and the viewing distance as being one of near, medium and far from the color television, and said fuzzy inference rules controlling the contrast, brightness and sharpness of the image in dependence upon said membership functions.

14. The picture adjusting circuit according to claim 12, wherein said means for generating said first, second and third signals comprises:

first sensor means coupled to receive said video signal from a tuner, for detecting the instantaneous magnitude of said video signal to provide said first signal;

second sensor means coupled to receive an output voltage of an automatic brightness limiter, for detecting the brightness of said image on the visual display to provide said second signal; and

third sensor means consisting essentially of a photo-resistor, for detecting the ambient light in the environment surrounding said visual display to provide said third signal.

15. The picture adjusting circuit according to claim 14, wherein said first sensor means comprises:

an input terminal coupled to receive said video signal;

an output terminal for providing said first signal representative of the instantaneous magnitude of said video signal;

a first resistor interposed between said input terminal and said output terminal; and

a second resistor interposed between said input terminal and ground.

16. The picture adjusting circuit according to claim 14, wherein said second sensor means comprises:

an input terminal coupled to receive the output voltage of the automatic brightness limiter;

an output terminal for providing said second signal representative of the brightness of said image on the visual display;

a first resistor interposed between said input terminal and a power source;

a second resistor interposed between said input terminal and said output terminal; and

a third resistor interposed between said second resistor and ground.

17. The picture adjusting circuit as claimed in claim 12, wherein said first signal is defined by said membership functions as magnitude of the video signal having an input status of one of weak, slightly weak, slight strong and strong, said second signal is defined by said membership function as brightness picture having an input status of one of dark, slightly dark, medium dark, slightly bright and bright, said third signal is defined by said membership functions as ambient light having an input status of one of dark, slightly dark, slight bright and bright, and said fourth signal is defined by said membership functions as distance between said visual display and said remote controller having an input status of one of near, medium and far from the color television, for respectively controlling the contrast, brightness and sharpness of the image in dependence upon the input status of each of said first, second, third and fourth signals.

18. A picture adjusting method of a television, comprising the steps of:

providing sensed signals varying in dependence upon values obtained by sensing an ambient brightness in an environment surrounding the television, sensing a picture brightness of a visual display provided on a display screen of the television, and sensing a magnitude of video signals representative of an image within said visual display;

generating, in response to reception of a remote control signal from a remote controller, a detected distance signal upon detection of a viewing distance between said remote controller and said television;

determining adjusted values selected from a plurality of fuzzy, inference rules and membership functions representative of different levels of contrast, brightness and sharpness of the image in dependence upon the sensed signals representative of the ambient brightness, the picture brightness, the magnitude of said video signals and the detected distance signal; and

adjusting the contrast, the brightness and the sharpness of the image according to said adjusted values.

19. A picture adjusting method for a television, comprising the steps of:

receiving video signals representative of an image formed on a display screen said television;

generating sensed signals by sensing an ambient brightness in an environment surrounding the color television, a picture brightness of the display screen and a magnitude of said video signals representing the image;

generating a detected distance signal in dependence upon detection of a viewing distance between a remote controller and said television;

determining adjusted values based on a plurality of membership functions each defining the ambient brightness as different ones of dark, slightly dark, slightly bright and bright, the picture brightness as different ones of dark, slightly dark, medium dark, slightly bright and bright, the magnitude of said video signals as different ones of weak, slightly weak, slight strong and strong, and the viewing distance as different ones of near, medium and far from the color television, and a corresponding plurality of fuzzy inference rules each controlling the contrast, brightness and sharpness of the image in dependence upon said membership functions in dependence upon reception of said detected distance signal and said sensed signals; and

adjusting the contrast, the brightness and the sharpness of the image on the display screen in dependence upon the adjusted values.