Method and apparatus for improving image quality

1. A method of improving an image quality of a video signal which is supplied on a frame-by-frame basis without creating a time zone in which a panel does not emit light during a period in which a frame is displayed, said method comprising:

extracting low frequency components from a video signal of an n-th frame, where n is a natural number excluding zero;

subtracting the extracted low frequency components from a video signal of an (n+m)th frame to produce high frequency components, where m is a natural number excluding zero; and

adding the produced high frequency components to the video signal of the (n+m)th frame,

wherein the extracted low frequency components comprise a horizontal component and a vertical component.

2. The image quality improving method according to claim 1 , further comprising:

extracting the low frequency components from the video signal of the n-th frame in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.

3. The image quality improving method according to claim 1 , wherein two-dimensional low frequency components are subtracted from a frame signal to obtain three-dimensional high frequency components, the frame signal being different from a frame signal in which the two-dimensional low frequency components are extracted.

4. The image quality improving method according to claim 1 , wherein the video signal of the n-th frame is delayed by m frames from the video signal of the (n+m)th frame.

5. The image quality improving method according to claim 1 , further comprising:

delaying the video signal of the (n+m)th frame by m frames to generate the video signal of the n-th frame before said extracting the low frequency components from the video signal of the n-th frame.

6. The image quality improving method according to claim 5 , wherein the video signal of the (n+m)th comprises a same input signal which is provided for said delaying the video signal of the (n+m)th frame, for said subtracting the extracted low frequency components from the video signal of the (n+m)th frame, and for said adding the produced high frequency components to the video signal of the (n+m)th frame.

7. A method of improving an image quality of a video signal which is supplied on a frame-by-frame basis without creating a time zone in which a panel does not emit light during a period in which a frame is displayed, said method comprising:

extracting high frequency components associated with a video signal of an n-th frame, where n is a natural number excluding zero;

adding the extracted high frequency components to a video signal of an (n+m)th frame, where m is a natural number excluding zero,

wherein the high frequency components extracted from the n-th frame comprise a horizontal component and a vertical component, the high frequency components added to the (n+m)th frame thereby making the (n+m)th frame three-dimensional, having horizontal, vertical, and temporal components, and

wherein said extracting high frequency components comprises subtracting two-dimensional low frequency components from the video signal of the n-th frame to produce the three-dimensional high frequency components; and

extracting low frequency components from the video signal of the n-th frame; and

subtracting the extracted low frequency components from the video signal of the n-th frame to produce the high frequency components.

8. The image quality improving method according to claim 7 , wherein said extracting the low frequency components from the video signal of the n-th frame is performed in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.

9. An apparatus for improving an image quality of an input video signal which is supplied on a frame-by-frame basis without creating a time zone in which a panel does not emit light during a period in which a frame is displayed, said apparatus comprising:

a low frequency component extractor that extracts low frequency components from a video signal of an n-th frame, where n is a natural number excluding zero;

a subtractor that subtracts the low frequency components extracted by said low frequency component extractor from the input video signal of an (n+m)th frame to extract the high frequency components, where m is a natural number excluding zero; and

an adder that adds the high frequency components to the input video signal of the (n+m)th frame,

wherein the extracted low frequency components comprise a horizontal component and a vertical component.

10. The image quality improving apparatus according to claim 9 , wherein said low frequency component extractor comprises:

a frame memory to delay the input video signal supplied on a frame-by-frame basis in units of frames; and

a low-pass filter that extracts low frequency components from the video signal delayed by said frame memory.

11. The image quality improving apparatus according to claim 10 , wherein said low-pass filter extracts the low frequency components from the video signal delayed by said frame memory in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.

12. The image quality improving apparatus according to claim 9 , wherein said low frequency component extractor comprises:

a horizontal low-pass filter that extracts the low frequency components of the input video signal supplied on a frame-by-frame basis in a horizontal direction of an image displayed by the video signal;

a down-sampler that reduces a number of samples in a video signal that has the low frequency components in the horizontal direction that have been extracted by said horizontal low-pass filter;

a frame memory to delay the video signal down-sampled by said down-sampler in units of frames;

a vertical low-pass filter that extracts the low frequency components from the video signal delayed by said frame memory in a vertical direction of the displayed image; and

an up-sampler that returns a number of samples in a video signal that has the low frequency components in the vertical direction that have been extracted by said vertical low-pass filter to the original number of samples.

13. The image quality improving apparatus according to claim 9 , wherein said low frequency component extractor comprises:

a first infinite impulse response (IIR) filter that extracts the low frequency components from the input video signal supplied on a frame-by-frame basis in at least one of a horizontal direction of the input video signal, and a vertical direction of the input video signal;

a first frame inverter that inverts a time-axis of a video signal that has the low frequency components that have been extracted by said first IIR filter;

a second IIR filter that extracts low frequency components from the video signal, the time-axis of which has been inverted by said first frame inverter, in at least one of a horizontal direction of the video signal, and a vertical direction of the video signal; and

a second frame inverter that inverts the time-axis of a video signal that has the low frequency components that have been extracted by said second IIR filter.

14. The image quality improving apparatus according to claim 9 , wherein said subtractor subtracts the low frequency components extracted by said low frequency component extractor from the video signal of the n-th frame to extract the high frequency components.

15. The image quality improving apparatus according to claim 14 , wherein said low frequency component extractor extracts the low frequency components from the video signal of the n-th frame in at least one of a horizontal direction of an image displayed by the video signal, and a vertical direction of an image displayed by the video signal.

16. The image quality improving apparatus according to claim 9 , wherein the video signal of the n-th frame is delayed by m frames from the input video signal of the (n+m)th frame.

17. The image quality improving apparatus according to claim 9 , further comprising:

a frame memory that delays the input video signal of the (n+m)th frame by m frames to generate the video signal of the n-th frame before that said low frequency component extracts the low frequency components from the video signal of the n-th frame.

18. The image quality improving apparatus according to claim 17 , wherein a same input signal comprising the input video signal of the (n+m)th frame is provided to said frame memory, said low frequency component, and said adder.

19. The image quality improving apparatus according to claim 9 , wherein said low frequency components comprise two-dimensional components, and the high frequency components comprise three-dimensional components.