Back to results
US 7,002,594 B2Granted
Image processing apparatus and image display apparatus using same
AssigneeSharp Kabushiki Kaisha
InventorsYasuhiro Yoshida, Hiroyuki Furukawa
Life of this patent
Estimating the term…
Abstract
An image processing apparatus of the present invention comprising (a) a first signal processing circuit for applying gamma correction to an n-bit (n: a natural number) digital signal inputted as a video signal and for converting the n-bit digital signal into an m-bit (m>n, m: a natural number) digital signal, and (b) a second signal processing circuit for adding a noise signal, which is used for pseudo contour reduction, into the m-bit digital signal from the first signal processing circuit and for outputting a Q-bit (Q: a natural number) digital signal, which is obtained from rounding off a less significant (m−Q) bit (Q≦n) from the m-bit digital signal, to a display section.
Claims58
An image processing apparatus, comprising:
- a first signal processing circuit for applying gamma correction to an n-bit (n:
- a natural number) digital signal inputted as a video signal, and for converting the digital signal into an m-bit (m>n, m:
- a natural number) digital signal;
- and
- a second signal processing circuit for adding a noise signal to the m-bit digital signal from said first signal processing circuit, and for outputting a Q-bit (Q:
- a natural number) digital signal obtained from rounding down a less significant (m−Q) bit (Q≦n) from the m-bit digital signal,
- wherein a histogram of an amplitude of the noise signal shows Gaussian distribution where zero amplitude of the noise signal is at the center.
4 more elements
An image processing apparatus, comprising:
- a signal processing circuit for adding a noise signal to an inputted m-bit (m:
- a natural number) digital signal, and for outputting a Q-bit (Q:
- a natural number) digital signal obtained from rounding down a less significant (m−Q) bit (Q<m) from the m-bit digital signal,
- wherein a histogram of an amplitude of the noise signal shows Gaussian distribution where zero amplitude of the noise signal is at the center.
1 more element
An image processing apparatus, comprising:
- a first signal processing circuit (a) for applying gamma correction to a digital video signal inputted therein, (b) for expanding a bit number of the digital video signal from n bit to m bit (m>n:
- n and m are natural numbers), and (c) for outputting the digital video signal;
- and
- a second signal processing circuit (d) for adding a noise signal to the digital signal thus outputted from the first signal processing circuit, (e) for converting the number of the digital video signal from m bit to Q bit by rounding down a less significant (m−Q) bit (Q≦n:
- Q is a natural number), and (f) for outputting the thus obtained digital video signal whose bit number is Q bit,
- wherein the noise generating circuit includes:
- an address counter for outputting pixel addresses, the pixel addresses being incremented, pixel by pixel, in a horizontal direction and incremented, line by line, in a vertical direction,
- a noise ROM for storing noise data enough for one screen, and for outputting the noise signal that is to be supplied per pixel, in accordance with the pixel addresses thus outputted from the address counter.
5 more elements
An image processing apparatus, comprising:
- a first signal processing circuit for converting an n-bit (n:
- a natural number) digital signal inputted as a video signal, into an m-bit (m>n, m:
- a natural number) digital signal;
- and
- a second signal processing circuit for adding a noise signal to the m-bit digital signal from said first signal processing circuit, and for outputting a Q-bit (Q:
- a natural number) digital signal obtained from rounding down a less significant (m−Q) bit (Q≦n) from the m-bit digital signal,
- wherein a histogram of an amplitude of the noise signal shows Gaussian distribution where zero amplitude of the noise signal is at the center.
4 more elements
An image processing method comprising the steps of:
- converting an n-bit (n:
- a natural number) digital signal inputted as a video signal, into an m-bit (m>n, m:
- a natural number) digital signal;
- adding a noise signal to the m-bit digital signal;
- and
- outputting a Q-bit (Q:
- a natural number) digital signal obtained from rounding down a less significant (m−Q) bit (Q≦n) from the m-bit digital signal,
- wherein a histogram of an amplitude of the noise signal shows Gaussian distribution where zero amplitude of the noise signal is at the center.
5 more elements
An image processing method comprising the step of:
- adding a noise signal to an m-bit digital signal (m:
- a natural number);
- and
- subsequently outputting a Q-bit (Q:
- a natural number) digital signal obtained from rounding down a less significant (m−Q) bit (Q<m) from the m-bit digital signal
- wherein a histogram of an amplitude of the noise signal shows Gaussian distribution where zero amplitude of the noise signal is at the center.
3 more elements
An image processing apparatus, comprising:
- a first signal processing circuit for processing with a predetermined operation an n-bit digital signal (n:
- natural number) inputted as a video signal to be converted into an m-bit digital signal (m>n, m:
- a natural number);
- and
- a second signal processing circuit for adding a noise signal to the m-bit digital signal inputted from said first signal processing circuit, rounding down a less significant (M−Q) bit (Q≦n) from the m-bit digital signal having added thereto the noise signal, and outputting the resulting Q-bit digital signal,
- wherein a histogram of an amplitude of the noise signal shows Gaussian distribution where zero amplitude of the noise signal is at the center.
3 more elements
An image processing method comprising the steps of:
- processing with a predetermined operation an n-bit digital signal (n:
- natural number) inputted as a video signal to be converted into an m-bit digital signal (m>n, m:
- a natural number);
- and
- outputting a Q-bit digital signal obtained by adding a noise signal to the m-bit digital signal and rounding down a less significant (m−Q) bit (Q≦n) from the m-bit digital signal having added thereto the noise signal,
- wherein a histogram of an amplitude of the noise signal shows Gaussian distribution where zero amplitude of the noise signal is at the center.
3 more elements
An image processing apparatus, comprising:
- a first signal processing circuit for converting an n-bit (n:
- a natural number) digital signal inputted as a video signal, into an m-bit (m>n, m:
- a natural number) digital signal;
- a second signal processing circuit for adding a noise signal to the m-bit digital signal from said first signal processing circuit, and for outputting a Q-bit (Q:
- a natural number) digital signal obtained from rounding down a less significant (m−Q) bit (Q≦n) from the m-bit digital signal;
- and
- a noise memory for storing the noise signal for one screen.
4 more elements
An image processing apparatus, comprising:
- a first signal processing circuit for converting an n-bit (n:
- a natural number) digital signal inputted as a video signal, into an m-bit (m>n, m:
- a natural number) digital signal;
- a second signal processing circuit for adding a noise signal to the m-bit digital signal from said first signal processing circuit, and for outputting a Q-bit (Q:
- a natural number) digital signal obtained from rounding down a less significant (m−Q) bit (Q≦n) from the m-bit digital signal;
- and
- a noise memory for storing the noise signal per block that is smaller than one screen.
4 more elements
Dependencies are inferred from the claim text.