1300 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.

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.

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.

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.

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.

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.