1318 results about "Gamma correction" patented technology

The gradation correction device includes a luminance signal convertor to generate a luminance signal from the input R, G, B signals, a correction coefficient calculator which calculates the ratio to the luminance signal of the luminance signal after gamma correction to the predetermined gradation characteristics, and a multipliers to multiply the output from the correction coefficient calculator by each of the R, G, and B input signals. When the gradation correction is applied, effective brightness adjustment can be applied with no change in hue and saturation and without exceeding the dynamic range of a device.

For two or more versions of a video with different spatial, temporal or SNR resolution, scalability can be achieved by generating a base layer and an enhancement layer. When a version of a video is available that has higher color bit depth than can be displayed, a common solution is tone mapping. A more efficient compression method is proposed for the case where the two or more versions with different color bit depth use different color encoding. The present invention is based on joint inter-layer prediction among the available color channels. Thus, color bit depth scalability can also be used where the two or more versions with different color bit depth use different color encoding. In this case the inter-layer prediction is a joint prediction based on all color components. Prediction may also include color space conversion and gamma correction.

Device and method for converting a format of a video signal in a digital TV receiver is provided. Format conversion can be carried out at one chip of a format converting device, inclusive of conversion of resolution, frame rate, scanning method, aspect ratio, color space, chroma format, and gamma correction. Therefore, the digital TV receiver is made to convert a wide range of video signals inclusive of, not only a digital TV broadcasting signal, but also analog TV broadcasting signal, and computer video signal, at one chip of system block. Moreover, the digital TV receiver is made to provide a variety of standards of format converted video signals, not only to the connected display, but also to other general video signal processing devices.

The resolution of text rendered on a display device having sub-pixel elements, such as an RGB LCD for example, and in particular, on a display device having horizontal striping is enhanced by (i) overscaling (or oversampling) character outline information in the vertical (or Y) direction, and (ii) filtering displaced information from the overscaled (or oversampled) character outline information. Metrics associated with character outline information may be appropriately adjusted. The vertical (or Y) position of the baseline of adjacent characters may be constrained by forcing the first pixel above the baseline to be composed of a full number N of scan conversion source samples, where N corresponds to an overscaling (or oversampling) factor. Groups of scan conversion source samples may be converted into packed pixel index values. Color values may be selectively filtered when the differences in the intensity of adjacent sub-pixel elements would otherwise be irritating to view. Finally, the gamma of the pixel values may be corrected so that the gamma of the display device is considered and so that intensity values of sub-pixel elements fall within a range of intensities in which gamma correction is more useful.

A CCD captures a subject image having passed through a taking lens and an image processing circuit performs various types of image pre-treatment including gamma correction and white balance on image data corresponding to n lines×m rows output by the CCD. The image processing circuit also performs format processing on the data. The data are then compressed at a compression circuit. The white balance adjustment and the like are implemented in line sequence at a line processing circuit which engages in signal processing in pixel sequence in units of individual lines in the output from the CCD. The image data having undergone the pre-treatment are then subjected to format processing prior to JPEG compression, at a block processing circuit that engages in signal processing in units of individual blocks each ranging over an n×m (N>n, M>m) block. In other words, the signal processing is performed in block sequence.

The present invention provides an apparatus for converting a video format of a digital TV and method thereof, by which various functions such as video format detection, color space conversion, chroma format conversion, gamma correction, geometric correction, image quality adjustment, and the like are implemented on one chip to support video signals of various specifications and display devices. The present invention includes an input video format detecting unit detecting a format of an input video, a format converting unit converting spatial resolution, frame rate, scan, aspect ratio, color space, and chroma format of the input video signal detected by the input video format detecting unit into a requested output format, a display characteristic correcting unit correcting the signal converted by the format converting unit to fit a display device, and an image quality adjusting unit adjusting an image quality of the corrected signal.

An image not subjected to color correction, gamma correction, MTF correction and others is used as an image to be subjected to Retinex image processing. Thus, a RAW image prepared only by converting an electric signal of a CCD image sensor by an A / D converter into a digital form is used as an image to be subjected to the Retinex processing. Predetermined gamma correction is performed after the Retinex processing. Thereby, Retinex algorithm substantially modeling functions of a retina and a cortex of a living body exhibits its original performance. The resolution of the original image is lowered, and processing is performed on an image thus produced to produce a blurred image. Then, the resolution of the blurred image is restored to the same resolution as that of the original image, and the Retinex processing is performed. Thereby, the Retinex processing can be performed without increasing memory consumption and extremely lowering an operation speed.

A graphics processor performed gamma correction of the coverage values of pixels. In one embodiment, a gamma correction factor is written into a run-time loadable lookup table of the graphics processor. The gamma corrected coverage values may be used in an anti-aliasing process to form smoothed primitives.

A display driving device for driving a plurality of display pixels provided with a light emitting element which performs color display, is provided with a signal converter which is supplied a display data including a plurality of color components corresponding to the plurality of display pixels and corresponds to a predetermined number of two or more display pixels having the light emitting elements of different light emission colors from each other, based on a single conversion characteristic, different gamma correction curves corresponding to the color component, which corresponds to the light emission color of each of the light emitting elements in the predetermined number of display pixels, are generated, the color component of the display data is converted with the use of each of the gamma correction curves, and a gradation signal for driving the light emitting element in each of the display pixels is generated.

A method of processing data from a digital image to optimize the tonescale to a printer being used without operator intervention adjusts the gain and offset of the input image data to occupy the full range of the printer, adjusts the shadow and highlight regions of the input image data to move that data distribution to that expected of the printer and then uses a gamma correction stage to move the mean level of the image data toward that expected for the printer.

A method of adjusting the N components of an N component colour signal (such as the 3 components of an RGB colour signal) with respect to colour temperature of illuminating light when imaging a coloured subject, comprising the step of computing the difference between each of the components of the colour signal for different temperatures of illuminating light, using an algorithm based on the spectral sensitivity of the imaging means and Planck's equation defining black body illumination to obtain N components whose values are independent of the colour temperature of the illuminating light. Normalisation of the adjusted values renders the values independent of intensity of illumination and can also reduce the processing time for further processing of the signals. A technique for compensating for gamma correction which is commonly built in cameras, is disclosed.

The present invention provides a technique for performing gamma correction processing when there are a plurality of characteristic areas, each of which is characterized by the high frequency in a luminance histogram to improve the impression of contrast. According to the present invention, a luminance characteristic detector (4) detects the luminance of an input image signal and a microcomputer (5) calculates an APL and a luminance histogram of an input image signal. A gamma correction circuit (6) performs the gamma correction processing in response to the luminosity of the input image signal by use of the result of the calculation carried out by the microcomputer (5). Then, if there are a plurality of characteristic areas, each of which is characterized by the high frequency in the luminance histogram, a characteristic emphasis circuit (7) performs grayscale extension processing for the plurality of characteristic areas. This makes it possible to perform the most suitable processing in response to the input image signal so that the impression of contrast is improved.

In a gamma correction digital-to-analog converter, one of first gamma correction reference voltage signals is selected as a first corresponding gray scale signal based on lower m+n bits of a k bit digital input signal when upper l bits of the k bit input signal correspond to an upper or lower code set, where k=l+m+n, and where k, l, m and n are integers. A pair of adjacent second gamma correction reference voltage signals is selected from second gamma correction reference voltage signals based on upper l+m bits when the upper l bits correspond to a middle code set, and one is selected from the pair of second gamma correction reference voltage signals and 2n−1 divided signals as a second corresponding gray scale signal, the divided signals being obtained by dividing an interval between the selected pair into 2n levels. The first or second gray scale signal is selected to be output.

A liquid crystal display and its driving method are provided which enable a proper gamma correction to be made to each of red, green, and blue colors without causing a decrease in a number of gray levels in an output image and enable lowering in an image quality to be prevented. The liquid crystal display includes a liquid crystal panel in which pixel electrodes for each of the red, green, and blue colors are repeatedly arranged along a scanning line, a scanning line driving circuit to scan in every scanning period, an RGB (Red, Green, and Blue) switching reference gray-scale voltage producing circuit to produce a reference voltage corresponding to a voltage-transmittance characteristic of each color, and a signal line driving circuit to produce a signal voltage and to feed to each signal line.

A system and method are described herein for controlling the white balance and providing gamma correction without compromising gray-scale dynamic range in a flat panel liquid crystal display (LCD). According to one embodiment of the present invention, the flat panel LCD includes electronic circuitry for coupling to a host computer to receive a white-balance adjustment control signal, and electronic circuitry for receiving image data to be rendered on the flat panel LCD. Further, the flat panel LCD of one embodiment is configured for coupling to a color-sensing device to receive optical characteristics data of the flat panel LCD detected by the color-sensing device. The white balance adjustment mechanisms include the provision of two or more light sources of differing color temperature, whose brightness can be independently varied (and distributed through a light distribution mechanism) to adjust color temperature without altering the grayscale resolution of the RGB colors. The present invention further includes white balance adjustment software and gamma correction software for generating white-balance adjustment control signals and appropriate gamma correction curves.

The invention relates to a gamma correction system and a method for LCDs. The gamma correction system consists of an LCD to be detected, a photoreceptor, and a microcontrol unit. The LCD to be detected displays each gray-stage picture according to parameter data and gray-stage voltage which are corresponding to a standard gamma curve which is stored therein. The photoreceptor senses and detects the actual display luminance of gray-staged pictures displayed by the LCD to be detected and transfers the actual display luminance into a voltage signal. The microcontrol unit compares the voltage signal which stands for actual display data with the parameter data corresponding to the standard gamma curve and adjusts the gray-stage voltage of the LCD to be detected according to the result of the comparison. The gamma correction system and the method for LCDs can realize automation of gamma correction.

There is provided a display device capable of automatically controlling a luminance in response to a brightness of a surrounding. The display device has a gamma correction circuit for converting an image signal voltage into a drive voltage for gray scale display and a photosensor for controlling an input and output voltage characteristic of the gamma correction circuit in response to the brightness of the surrounding. In this case, the gamma correction circuit for converting the image signal voltage into the driver voltage for gray scale display is formed on a first substrate. The photosensor for controlling the input and output voltage characteristic of the gamma correction circuit in response to the brightness of the surrounding is formed on a second substrate. The second substrate is fixed to the first substrate.

A display signal processing device includes a reference gradation voltage generating circuit that generates ten reference gradation voltages, and a D / A converting circuit that converts a video signal to a pixel voltage by selectively using the ten reference gradation voltages obtained from the reference gradation voltage generating circuit. The reference gradation voltage generating circuit includes four variable voltage generating sections that generate output voltages, which are varied for gamma correction, and nine resistors that are connected to divide difference voltages obtained between output terminals of the four variable voltage generating sections into the ten reference gradation voltages.

The invention discloses a gamma voltage correction method and device, relates to the field of display, and can solve the present problem of long time of gamma correction so that production efficiency can be enhanced. The gamma voltage correction method comprises the steps that S1, data voltage corresponding to characteristic gray scale points is acquired; S2, gamma register values corresponding all binding point gray scales are acquired; S3, fine adjustment is performed: the gamma register values of all the binding point gray scales are inputted to a display module group, based on which fine adjustment is performed on the optical parameters of all the gray scales; and S4, testing is performed: a gamma curve of the display module group is tested and compared with a target gamma curve, and the step S3 is continuously performed if the gamma curve does not meet the requirements of product specifications until the display module group meets the requirements of the product specifications.

An electronic endoscope selector that is used in an electronic endoscope system which shares peripheral devices, such as a TV monitor, VCR etc., among a plurality of electronic endoscopes. The electronic endoscope selector comprises switching circuits for switching and selecting video signals and synchronization signals fed from one of the plurality of electronic endoscopes. The selector also comprises amplifiers, gamma correction circuits, a system control circuit and memory. The amplifiers and gamma correction circuits are for adjusting gains and gamma correction of RGB video signals fed from the selected electronic endoscope. Parameters for appropriate gains and gamma correction corresponding to each endoscope are stored in the memory. The system control circuit controls the amplifiers and gamma correction circuits in accordance with the parameters that correspond to the selected electronic endoscope.

An image enhancement method and system are provided. The image enhancement method and system are capable of improving image quality by performing gamma corrections on global and local illuminations and reflectance estimated from an input image, in consideration of dynamic range and contrast of the image, respectively. Particularly, in a case of a color image, the red, green, and blue (RGB) component images are converted into hue, saturation, and value (HSV) component images, and the global and local illuminations and reflectance estimated from the V component image. By converting the hue (H), saturation (S), and enhanced value (V) into RGB, an enhanced color image can be obtained.

The invention discloses a strip steel surface area type defect identification and classification method which comprises the following steps: extracting strip steel surface pictures in a training sample database, removing useless backgrounds and keeping the category of the pictures to a corresponding label matrix; carrying out bilinear interpolation algorithm zooming on the pictures; carrying out color space normalization on images of the zoomed pictures by adopting a Gamma correction method; carrying out direction gradient histogram feature extraction on the corrected pictures; carrying out textural feature extraction on the corrected pictures by using a gray-level co-occurrence matrix; combining direction gradient histogram features and textural features to form a feature set, which comprises two main kinds of features, as a training database; training the feature data with an improved random forest classification algorithm; carrying out bilinear interpolation algorithm zooming, Gamma correction, direction gradient histogram feature extraction and textural feature extraction on the strip steel defect pictures to be identified in sequence; and then, inputting the feature data into an improved random forest classifier to finish identification.

Disclosed herein is an apparatus for enhancing images in consideration of region characteristics. An inverse gamma correction unit releases gamma correction and linearizes each of Red (R), Green (G), and Blue (B) colors. A threshold calculation unit calculates m-1 thresholds in order to divide the brightness of pixels into m regions, and labels each of the pixels as one of the m brightness regions. A block segmentation unit divides an input image into M×N blocks. A block statistics calculation unit determines one of the m brightness regions to which each of the blocks pertains, and labels the block as the corresponding brightness region. A block-based Look-Up Table (LUT) generation unit generates enhancement LUTs for the respective blocks. An image enhancement unit corrects the image using the LUTs for the respective blocks. A gamma correction unit performs gamma correction.

The invention discloses a gamma correction method and device, a display device and a computer storage medium, belonging to the technical field of display. The method comprises the following steps: acquiring measurement data of a sample display panel, wherein the measurement data is used for recording at least one display brightness and compensating parameters corresponding to a to-be-compensated gamma curve under each display brightness; acquiring a gamma curve under each display brightness in at least one display brightness of each to-be-corrected display panel; and respectively compensatingthe gamma curve under each display brightness by virtue of the corresponding compensating parameters of the gamma curve under each display brightness in the measurement data until a gamma value corresponding to each compensated gamma curve is in a standard error range, wherein the to-be-corrected display panels and the sample display panel are produced in the same batch. The gamma correction method can solve the problems that the consumed time of a gamma correction process is relatively long, and the gamma correction efficiency is relatively low in relevant techniques.

Disclosed herein is an imaging apparatus for performing predetermined image signal processing on an image signal picked up by an image pickup device in order to convert the image signal for recording and display purposes, the imaging apparatus including, a parameter storage section, a parameter setting section, a gamma correction processing section, and a display-ready signal conversion section.

A display device and a driving method thereof in which if an input 2D / 3D video signal is a 2D video signal, an image data signal is generated by applying a first gamma correction curved line. If the input 2D / 3D video signal is a 3D video signal, an image data signal is generated by applying the second gamma correction curved line. Luminance of a maximum grayscale of the first gamma correction curved line is set to be lower than luminance of a maximum grayscale of the second gamma correction curved line. Therefore, it is possible to prevent luminance of the display device from deteriorating by a barrier in a 3D driving mode.

A dynamic Gamma correction circuit, method thereof and a panel display apparatus are provided. The panel display apparatus has a timing controller, a dynamic Gamma correction circuit, a display panel and a display driving circuit. The timing controller receives a first image data and output a second image data. The dynamic Gamma correction circuit receives and analyzes the first image data so as to correct and output a plurality of Gamma voltages. The display driving circuit electrically connects to the display panel, the timing controller and the dynamic Gamma correction circuit for receiving the second image data and the Gamma voltage so as to drive the display panel.

In an embodiment, a host computing device includes an internal display and also includes a connector to connect to an external display. A cable is provided to connect to the connector and to connect to the external display. The cable includes video processing capabilities. For example, the cable may include a memory configured to store a frame buffer. The frame buffer may store a frame of video data for further processing by the video processing device in the cable. The video processing device may manipulate the frame in a variety of ways, e.g. scaling, rotating, gamma correction, dither correction, etc.

The invention discloses a peripheral compensation system of a pixel matrix, a method thereof and a display system. The peripheral compensation system comprises a grid scan driving module 200, a column data driving module 300 and a compensation module 400. The compensation module 400 is respectively connected with M columns of pixel units 101 via M columns of feedback signal lines and is used for detecting the variation of the electrical characteristics of a pixel matrix 100 so as to send a second display signal to the pixel matrix 100 and compensate each of the pixel units 101. According to the technical scheme of the invention, the addition of first display signals and second display signals in the pixel units is realized, so that accurate gamma correction of first display signals is realized at the same time. Meanwhile, the structure is simple. A first digital-to-analog conversion module and a second digital-to-analog conversion module are also low in the number of bits. On the condition that the addition mode of analog domains is conducted, an original high-voltage analog adder can be converted to a medium-voltage adder or a low-voltage adder.