Method and apparatus for improving image quality
A method (and apparatus) of improving an image quality of a video signal which is supplied on a frame-by-frame basis, includes extracting high frequency components associated with a video signal of an n-th frame (where n is a natural number), and adding the extracted high frequency components to a video signal of an (n+m)th frame (where m is a natural number).
1 . A method of improving an image quality of a video signal which is supplied on a frame-by-frame basis, comprising:
extracting high frequency components associated with a video signal of an n-th frame, where n is a natural number; and
adding the extracted high frequency components to a video signal of an (n+m)th frame, where m is a natural number.
2 . The image quality improving method according to claim 1 , further comprising:
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+m)th frame to produce the high frequency components.
3 . The image quality improving method according to claim 2 , 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.
4 . The image quality improving method according to claim 1 , further comprising:
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.
5 . The image quality improving method according to claim 4 , 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.
6 . An apparatus for improving an image quality of an input video signal which is supplied on a frame-by-frame basis, comprising:
a high frequency component extractor that extracts high frequency components associated with a video signal of an n-th frame, where n is a natural number; and
an adder that adds the high frequency components extracted by said high frequency component extractor to a video signal of an (n+m)th frame, where m is a natural number.
7 . The image quality improving apparatus according to claim 6 , wherein said high frequency component extractor comprises:
a low frequency component extractor that extracts low frequency components from the video signal of the n-th frame; and
a subtractor that subtracts the low frequency components extracted by said low frequency component extractor from the input video signal to extract the high frequency components.
8 . The image quality improving apparatus according to claim 7 , wherein said subtractor subtracts the low frequency components extracted by said low frequency component extractor from the video signal of the (n+m)th frame to extract the high frequency components.
9 . The image quality improving apparatus according to claim 8 , 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.
10 . The image quality improving apparatus according to claim 9 , 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.
11 . The image quality improving apparatus according to claim 8 , wherein said low frequency component extractor comprises:
a horizontal low-pass filter that extracts 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 the 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 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 the 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.
12 . The image quality improving apparatus according to claim 8 , wherein said low frequency component extractor comprises:
a first infinite impulse response (IIR) filter that extracts 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.
13 . The image quality improving apparatus according to claim 7 , 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.
14 . The image quality improving apparatus according to claim 13 , 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.
15 . The image quality improving apparatus according to claim 6 , further comprising:
a multiplier that adjusts the amplitude of a high frequency component signal supplied from said high frequency component extractor.
16 . A display apparatus comprising:
the image quality improving apparatus according to claim 6;
a display device; and
a driving circuit that drives said display device based on a video signal supplied from said image quality improving apparatus.
17 . A method of improving an image quality of a video signal which is supplied on a frame-by-frame basis, comprising the steps of:
a step for extracting high frequency components associated with a video signal of an n-th frame, where n is a natural number; and
a step for adding the extracted high frequency components to a video signal of an (n+m)th frame, where m is a natural number.
18 . An apparatus for improving an image quality of an input video signal which is supplied on a frame-by-frame basis, comprising:
means for extracting high frequency components associated with a video signal of an n-th frame, where n is a natural number; and
means for adding the high frequency components extracted by said high frequency component extractor to a video signal of an (n+m)th frame, where m is a natural number.