Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Hironobu Yasui

Akinori Heishi

Hideki Yoshii

Koji Minami

Masaaki Hanai

Takashi Fujiwara

Yoshinori Miyamoto

Noritaka Okuda

Yoshitomo Nakamura

Toshihiro Gai

Akira Ishimori

Nobuhiko Yamagishi

Hiroaki Nishino

Hiroaki Sugiura

Yoshiaki Kato

Satoshi Yamanaka

Jun Someya

Kazuhiko Tsutsumi

Kazuo Kyuma

Toshiyuki Shimizu

Isao Otsuka

Shotaro Moriya

Junko Shinohara

Tomonori Fukuta

Shuji Sotoda

Yuka Tsuda

Chihiro Sakuwa

Takashi Hatakenaka

Tetsuya Shimizu

Haruo Shigematsu

An image processing device includes: a calculator that calculates a gray scale histogram for each color component of an image signal; a calculator that calculates, for each color component, a maximum and a minimum of classes having a frequency greater than zero in the gray scale histogram; a determiner that generates, for each color component, a histogram having classes each having an absolute difference value between the frequencies of adjacent classes in the gray scale histogram, and compares the absolute difference values in the histograms with a value to determine, from the presence or absence of an absolute difference value exceeding the value, an image type of the image; a generator that generates a gray scale correction curve from the calculated maximum and minimum for each color component; and a corrector that performs gray scale correction on the image signal using the gray scale correction curve.

Image processing device and image processing method

An image display device includes a liquid crystal panel section, a light source section divided into a plurality of regions, a light detection section detecting the light intensity of the light source section, and a timing generation section. The timing generation section generates a light emission drive signal which turns on each of the regions of the light source section according to scanning in the liquid crystal panel section, and which turns on all the regions of the light source section in a light detection period, and generates a light detection gate signal allowing the detection of the light detection section to be effective in the light detection period.

Image display device

A stereoscopic image display device includes a liquid crystal panel section, a light source section, a light detection section, a light source control section, a shutter glasses section, and a timing generation section generating a light emission drive signal, a light detection gate signal, and shutter switching signals in synchronization with an image synchronization signal. The timing generation section, generates the light emission drive signal which causes each of the regions of the light source section to emit light in accordance with scanning performed in the liquid crystal panel section, and which causes all the regions of the light source section to emit light in a predetermined period, and generates the light detection gate signal which enables detection of the light detection section in the predetermined period, and generates the shutter switching signals for switching left and right shutters to a non-transmissive mode.

Stereoscopic image display device

A light source portion includes a plurality of back lights provided corresponding to respective regions obtained by virtually dividing a liquid crystal panel screen into a plurality of parts, the back lights have a light emission intensity controlled based on a light emission intensity value and have ON and OFF operations controlled in response to a light emission driving signal, and the light emission driving signal is constituted to sequentially turn ON the plurality of back lights synchronously with a stereoscopic image signal and to turn ON the plurality of back lights at the same time in a predetermined timing, and is constituted to individually control a light emission period for the plurality of back lights based on image information about the stereoscopic image signal.

An image processing apparatus is obtained which is capable of performing gray-level correction while maintaining real-time property and accurately recognizing the feature of content obtained from an image signal. A luminance information detecting block detects a luminance information value about individual pixels from a luminance signal contained in an image signal. On the basis of the luminance information value, a content feature detecting block determines the feature of one frame of the video content, and obtains a content feature judge information value. On the basis of the content feature judge information value, a multiple content feature detecting block detects the feature of multiple frames of the video content, and outputs a multiple content feature judge information value to an image quality adjustment control block in an image quality adjusting block. On the basis of the multiple content feature information, the image quality adjustment control block calculates a correction parameter that is used when an image quality adjustment carrying-out block applies gray-level correction etc. to the image signal, and outputs the correction parameter to the image quality adjustment carrying-out block.

Image display apparatus

There are provided a first intermediate image generating means () for generating a first intermediate image (D) by extracting a component in a vicinity of a particular frequency band in an input image (DIN), a second intermediate image generating means () for generating a second intermediate image (D) from the first intermediate image (D), and an adding means for adding the input image (DIN) and the second intermediate image (D). The second intermediate image generating means () includes a non-linear processing means (A) that varies the content of its processing according to the pixel in the intermediate image (D). Even if the input image includes a fold-over component on the high-frequency side or does not include an adequate high-frequency component, adequate image enhancement processing can be carried out.

Image processing apparatus and method and image display apparatus

A frame interpolation apparatus generates a pixel value at an interpolation position by examining pairs of pixel blocks, one from a preceding reference frame and one from a following reference frame, located in positions that are point-symmetric or nearly point-symmetric with respect to the interpolation position. The pair of pixel blocks showing the greatest mutual similarity is selected, the central pixels in the selected pair of pixel blocks are taken as reference pixels, and the interpolated pixel value is generated from the reference pixel values. By routinely examining a large number of pairs of pixel blocks for each interpolation position, the frame interpolation apparatus can detect image motion accurately and generate accurate interpolated values.

Frame interpolation apparatus and frame interpolation method

A noise reducer for a signal determines a direction of correlation for each picture element (pixel) by calculating sums of absolute differences between a block centered on the pixel and neighboring blocks centered on surrounding pixels and choosing the direction of the neighboring block with the least sum of absolute differences. The pixel is then filtered one-dimensionally by averaging it with neighboring pixels located in the direction of correlation. This noise reduction method is simple, reliable, and avoids needless loss of detail.

Noise reducer for video signals

A video display apparatus generates luminance information for individual frames of a video signal from histograms of the luminance component of the video signal, and classifies the content of the video signal on the basis of this information. Color saturation information is also generated from color saturation histograms, and scene changes are detected. Video correction parameters and display control parameters are derived from the content classification and color saturation information. The video signal is corrected according to the video correction parameters, and displayed according to the display control parameters. Display characteristics suitable for the video content are thereby obtained. The parameters are changed when a scene change is detected, so that the viewer is not disturbed by the change in video display characteristics.

Video display apparatus that adjusts video display parameters based on video picture type

A CRT display apparatus capable of displaying images in high contrast and high brightness without causing noises and halftone-reproduction degradation within dark areas is disclosed. The apparatus includes a circuit for generating an R-control signal, a G-control signal and a B-control signal by removing, from each of the R-, G- and B-video signals, portions which are below a predetermined level in amplitude, an amplification circuit for inverting and amplifying the R-, G- and B-control signals, and a selection circuit for selecting, for each of the three G1 electrodes, either a corresponding one of the R-, G- and B-control signals inverted and amplified by the amplification circuit or a potential of a predetermined value in accordance with an instruction from an outside, and applying each of the three G1 electrodes with a selected one of the corresponding one of the R-, G- and B-control signals and the potential.

CRT display apparatus

When an interval between a Gm electrode and a cathode is broadened with temperature, a potential change similar to a case that a Gm electrode voltage is lowered is generated. If a cathode voltage is constant, a quantity of electrons which pass is decreased whereupon a screen of a cathode ray tube becomes dark. A Gm electrode voltage control circuit is provided to a Gm electrode voltage source for control an applied voltage to the Gm electrode by time information from a time-measuring circuit such that the change of the interval between the cathode and the Gm electrode is corrected during a period of time between the time the voltage is applied to each electrode of a Hi-Gm tube and the time the change of a size of the interval between the cathode and the Gm electrode is saturated.

Cathode ray tube display device and cathode ray tube display method

In a CRT display device including a CRT (MM tube) having brightness higher than that in the background-art CRT, it is an object of the present invention to improve contrast and prevent conspicuous recognition of noises. A video signal modulation circuit ( ) modulates a video signal ( ) (first video signal) into a second video signal having a signal level in an area of low gradation level lower than a signal level of the first video signal. A cathode bias voltage source ( ) generates a driving voltage on the basis of the second video signal. It is therefore possible to keep the driving voltage in the area of low gradation level low and reduce brightness in the area of low gradation level of a CRT ( ). As a result, noises of an image in the area of low gradation level are not conspicuously recognized and a contrast value is increased, resulting in improvement in image quality.

CRT display device

A CRT display apparatus including a CRT having an electron gun is disclosed. The electron gun includes a cathode, and a G electrode, a G electrode and a G electrode disposed in that order for drawing electrons from the cathode. The electron gun further includes a modulating electrode disposed between the G electrode and the G electrode. The CRT display apparatus is provided with a controller for controlling a value of a voltage applied to the modulating electrode in order to suppress or interrupt an electron beam flowing from the cathode to a screen of the CRT.

A cutoff adjustment method of a CRT using a Hi-Gm tube is proposed as well as a problem that luminance of a display screen is changed by a fluctuation of a Gm voltage to be applied to a Gm electrode in relation to fluctuations of currents flowing into the Gm electrode and a G2 electrode is solved. On this occasion, the cutoff adjustment method of the Hi-Gm tube sets such that a Gm voltage value of a Gm electrode voltage source and a black level bias voltage value applied to a cathode for displaying a black level agree with each other. Further, the CRT display device having the Hi-Gm tube is constituted such that it is provided with a voltage detection circuit in an output side of the Gm electrode voltage source for measuring a fluctuation of an output voltage from the Gm electrode voltage source to keep the Gm voltage constant by a feedback from the voltage detection circuit.

CRT display device and cutoff adjustment method

A display apparatus includes a CRT, the CRT including an electron gun having a cathode, a G1 electrode, a G2 electrode, and a G3 electrode disposed in that order to draw electrons from the cathode. The electron gun further has a modulating Gm electrode disposed between the G2 and G3 electrodes. The display apparatus is provided with a controller for controlling a value of a voltage applied to the Gm electrode to adjust brightness of a picture on a screen of the CRT.

Growing community of inventors

Tokyo, Japan

Hironobu Yasui