Abstract: The object of the present invention is to improve the quality of picture in the image.

Abstract: A signal process for interpolating color signals is executed. In this process, color image data output from image sensor covered by a plurality of color filters that form a predetermined matrix is interpolated, horizontal and vertical correlation levels are discriminated on the basis of the color image data, first color difference signals are calculated by color-separating interpolated image data of respective colors in a direction with the higher correlation level on the basis of the discrimination result, and second color difference signals are calculated by a predetermined arithmetic operation different from first color difference signal calculation unit on the basis of the interpolated image data of respective colors. The calculated first or second color difference signals are selected and output based on the first and second color difference signals.

Abstract: A method for detecting intensity saturation of a light sensor includes monitoring an electrical signal from a light sensor for detecting an intensity saturation condition of at least one pixel of the light sensor, converting the electrical signal to a digital signal, imposing a reserved bit combination on the digital signal indicating the intensity saturation condition of the pixel, and transmitting a control signal in response to the digital signal to compensate for the intensity saturation condition of the pixel.

Abstract: A method of improving a digital image captured by a digital camera comprising: providing a digital camera having a memory for storing known values of a color chart having a plurality of color patches of different colors and a digital image processor, using the digital camera to capture an image of the color chart to produce image values of the color patches of the color chart; operating the digital image processor to process at least some of the color patch imaged values and the stored known values of the color patches to produce a color correction matrix or profile; and storing the color correction matrix or profile to correct color images subsequently acquired by the digital camera.

Abstract: The color balance adjusting device comprises buttons, indicated on a surface of a display device, which can be moved rightward and leftward on the surface, by dragging a mouse. In accordance with the displacement of the buttons, gains of a red component signal, a green component signal and a blue component signal are changed. When a value of pixel data of one of the color components exceeds a saturation range, due to the gain adjustment, the color of a part of the color image indicated on a surface of a display device, in which the saturation occurs, is altered. Further, a comment, implying the occurrence of saturation, is generated by the display device.

Abstract: Of three-color signals R′, G′ and B′, obtained as output signals of multipliers 156R, 156G and 156B, designed to effectuate luminance compression of the three-color signals R, G and B sent to input terminals 151R, 151G and 151B by multiplying the signals R, G and B with a coefficient k, in such a manner as to maintain saturation and color hue of the three-color signals R, G and B, only the saturation of color video signals represented by the three-color signals R′, G′ and B′ is compressed by first saturation compression circuits 160R, 160G and 160B so that the signal level of the signal of the three-color signals R′, G′ and B′ having the highest signal level will be the clip level.

Abstract: Aiming to improve color reproducibility of a red part having high color saturation, a gamma compensation apparatus of the present invention is composed of a bending point setting block 100a and a gamma compensation block 101a and bending point setting block 100a is composed of a high APL detection circuit 1a inputting an average picture level of an input luminance signal and for detecting and taking out a signal component higher than a designated level; a gain controller 2a for gain controlling the detected signal at the high APL picture detection circuit; and an adder 3a for adding a designated offset to the output of gain controller 2a, and gamma compensation block 101a is composed of a slice circuit 4a inputting a color difference signal (R-Y) and the output of bending point setting block 100a and taking out a color difference signal component higher than the output signal level of bending point setting block 100a; a gain controller 5a for adjusting the output level of slice circuit 4a; and a subtracter 6a

Abstract: A level compression and/or gradation conversion of a video signal are performed without causing any change in the hue of a picture represented by that video signal. The knee compression and/or gradation conversion are carried out by multiplying red, green and blue primary color signals by a luminance gain, while the hue and saturation remain unaffected. If the level of any of the primary color signals still exceeds a predetermined threshold level, the saturation conversion is executed by using the saturation gain and the luminance component supplied from a controller. In the saturation conversion operation, the maximum level of at least one of the red, green and blue primary color signals is made coincident with the predetermined threshold level while the hue and luminance of the picture represented by the video signal are maintained unchanged.

Abstract: Disclosed is an image processing method of expanding the dynamic range by determining a saturated or noise region in an image signal and replacing the image signal with a proper image signal. A threshold value is set in units of colors on the basis of a standard image signal for each color, which is obtained upon sensing an image in a standard exposure, and a non-standard image signal for each color, which is obtained upon sensing the image in a non-standard exposure. A saturated or noise region is determined by applying the threshold value set in units of colors to the standard image signal. A region determined as a saturated or noise region is replaced with the non-standard image signal.

Abstract: A color signal processing circuit of a camera DSP chip for use with a CCD includes a matrix circuit for converting color signals from the CCD into R-G and B-G signals, a hue/gain controlling circuit for multiplying the R-G signal by a R-hue coefficient and a R-gain coefficient and multiplying the B-G signal by a B-hue coefficient and a B-gain coefficient to form B-Y and R-Y signals by adding the R-G and B-G signals respectively multiplied by respective hue and gain coefficients, a zoom-processing circuit for zoom-processing the B-Y and R-Y signals converted in the hue/gain controlling circuit in a zoom mode, and a frequency converting circuit for synchronizing the B-Y and R-Y signals from the hue/gain controlling circuit or zoom-processed in the zoom-processing circuit with a clock having the frequency four times as large as a color burst signal to provide synchronized signals while loading the color burst signals.

Abstract: There is provided a signal processing apparatus for processing input three primary color signals, which is capable of providing natural color reproduction. Input color signals R to B are subjected to a matrix operation to obtain color difference signals (R-Y)0 and (B-Y)0. The color signals R to B are compressed by means of high luminance compression circuits 12R to 12B, respectively, and these output color signals R1, G1 and B1 are subjected to obtain a luminance signal Y1, color difference signals (R-Y)1 and (B-Y)1. The respective outputs obtained from the matrix operation are operated by means of look-up tables 43 to 45 and 52 to obtain color difference signals (R-Y)3 and (B-Y)3 for representing a color which has the same hue as a hue .theta. 0 of color represented by color signals R to B and a saturation same with the saturation r1 of color represented by color signals R1, G1 and B1.

Abstract: An image reading apparatus in which reference density data corresponding to a reference document having a predetermined reference density is stored in advance, while a plurality of gamma correction curves are also stored in advance. Light intensity data indicative of the intensity of light reflected from the reference document is subjected to a shading correction. One gamma correction curve is selected from the plurality of gamma correction curves in correspondence to a difference in output level between the reference density data and outputted density data obtained by converting the shading corrected light intensity data. Gradation of the outputted density data is adjusted based on the selected gamma correction curve.

Abstract: A video camera system and method for automatically controlling the exposure of a desired object image. A plurality of average luminance values are respectively determined by a plurality of light measurement units. A plurality of reference luminance values are obtained from a plurality of reference value circuits. Selected ones of the average luminance values and the reference luminance values are utilized to form control signals. Such control signals control the video camera so as to maintain a proper exposure of the desired object.

Abstract: In an image pickup device for generating a corrected luminance signal by subtracting two color difference signals as correction signals from a luminance signal, a correction signal is generated by base-clipping at least one of the two color difference signals.

Abstract: A knee circuit in which the hue on the output side does not differ from the hue on the input side. The knee circuit includes a virtual luminance signal generator for generating a virtual luminance signal Y based on at least one input color signal Rin, Gin and Bin, a virtual correction value generator for monitoring whether the virtual luminance signal Y is equal to or greater than a knee point NP and for generating a virtual correction value Yk by performing a knee correction with respect to the virtual luminance signal Y when it is equal to or greater than the knee point NP. A proportional value generator generates a proportional value Kk showing a ratio of the virtual correction value Yk to the virtual luminance signal Y by dividing the virtual correction value Yk by the virtual luminance signal Y.

Abstract: A signal level adjusting circuit for performing adjustment of signal levels in which the levels of individual image signals are made uniform so as to provide greater use of a dynamic range on an image sensor without deterioration to resolution.

Abstract: An image pickup device comprises variable gain control circuits 11-13 and 23-25 for respective channels of digital color signals and luminance signals to control the gains by a gain control signal SG. Since the gains are variable in the digital signal channels, the deterioration of the image quality is reduced. The number of input bits of the variable gain control circuits is larger than the number of output bits to minimize the deterioration of the signal due to the loss of digits in coefficient circuits in the variable gain control circuits.

Abstract: It is an object to avoid suppression of color signals before a green color signal G reaches a saturation detection level Gdet or before each of color signals R and B reaches its saturation level to thereby substantially faithfully reproduce color of an object. To this end, a high luminance color suppressing circuit includes a virtual luminance signal generator for generator for generating a virtual luminance signal Y based on at least one signal of input color signals Rin, Gin and Bin, a coefficient generator for generating a first through a third coefficient K.sub.1 through K.sub.3 based on a saturation detection level Gdet, a virtual detection level Gth, and maximum output levels Rmax and Bmax, and an output color signal generator for generating output color signals Rout, Gout and Bout based on the virtual luminance signal Y, a minimum coefficient K.sub.0 and the color signals Rin, Gin and Bin.

Abstract: In an image pickup device for generating a corrected luminance signal by subtracting two color difference signals as correction signals from a luminance signal, a correction signal is generated by base-clipping at least one of the two color difference signals.

Abstract: In an image pickup apparatus, R, G and B three-primary-color signals are generated without reducing the saturation of colors and the band of the signals, while suppressing the generation of pseudocolors as much as possible, and image signals suitable for apparatuses, such as computers, printers and the like, are generated. A plurality of circuits for estimating the complementary-color value of a missing pixel are provided, and the output of one of the circuits is selected.

Abstract: A system for generating and displaying a contrast false color overlay as a focus assist includes a signal divider, an automatic gain control unit, an adder, a signal reducer and a signal combiner. The signal divider receives a signal representing an image and divides the signal into a red channel signal, a green channel signal and a blue channel signal. The red, green and blue channel signals are input to the signal reducer and respectfully reduced by a percentage value. The reduced Green and Blue channel signals are input to the signal combiner and combined with the output of the adder. A luminance signal is also input or generated from the channel signals and is fed to the automatic gain control unit which produces a contrast signal whose brightness is proportional to the contrast in the image. The contrast signal is input to the adder along with a reduced version of the red channel signal where the two signals are added together, and the output of the adder is provided to the combiner.

Abstract: An image sensing apparatus having a small amount of circuitry and exhibiting little power consumption is characterized in that a required delay line is connected into the circuitry at a point after a gamma-corrector in a digital signal processing system that processes an intensity signal, and another required delay line is connected into the circuitry at a point after a limiter in a corrective-signal generating system, which is for generating a signal that corrects a color signal. As a result, the delay lines are provided in fewer stages and need only have a small bit width. This makes it possible to reduce the amount of circuitry as well as power consumption.

Abstract: An inexpensive, yet robust color matcher is achieved by an apparatus which includes a compare device coupled to receive, as a first input, an input signal representing a combination of a luminance component Y and a chrominance component, and further coupled to receive as a second input, a threshold T, for comparing the input signal to the threshold T and outputting a color match signal if the input signal falls within a range defined by T and -T; and a threshold supply device coupled to the second input for supplying the threshold T, wherein the threshold T is a function of Y and at least two adjustable parameters.

Abstract: A simultaneous electronic endoscope apparatus which is capable of preventing the deterioration of the picture quality due to the difference of the saturation property in mixture signals. The apparatus comprises a charge coupled device provided with a plurality of color filters. Upper and lower pixel signals are mixed in a charge coupled device so as to form mixture signals. When the saturated state of a mixture signal is detected, the gain of the mixture signal is multiplied by a preset coefficient so as to apparently cancel the saturated state. Alternatively two types of luminance signals may be formed by combining the plurality of mixture signals formed on each horizontal scanning line. When the saturated state of a luminance signal is detected, the gain of the luminance signal is amplified so that the level thereof is the same as that of the other luminance signal, thereby apparently cancelling the saturated state.

Abstract: A video camera system can track or follow the moving object without influence by other objects outside the desired image. Detection feature patterns are formed after brightness and hue frequency feature data is obtained on the basis of image information of the detection measurement frame. The position of the detection measurement frame having a feature pattern with the largest similarity to the standard feature pattern obtained from the standard measurement frame is determined. An imaging condition of a camera is controlled on the basis of the position information of the detection measurement frame.

Abstract: A digital video camera includes a pseudo-saturation calculating circuit by which a pseudo-saturation corresponding to an actual saturation is calculated on the basis of two color difference signals, and a suppression coefficient is calculated by a suppression coefficient calculating circuit on the basis of the pseudo-saturation. Each of the color difference signals are outputted by a selecting circuit in a dot sequential manner, and multiplied by the suppression coefficient in a multiplying circuit. Therefore, a signal in which a low-saturation chrominance signal is outputted from the multiplying circuit, whereby the low-saturation chrominance signal can be suppressed even though a sampling frequency is not increased.

Abstract: There are disclosed electronic imaging systems employing CCD imaging units and one or more unique analog signal processors (ASP's). Each ASP receives color-component image signals from the CCD unit and provides respective output image signals, such as red, green and blue color components, having proper white balance for combining into a full color image. The dark background or zero level of the output image signals is referenced to a common "dark" reference voltage to minimize dark background variations in the combined color image regardless of the gain setting of the ASP or ASP's. Each ASP is substantially identical and has a unique architecture which facilitates its implementation as an integrated circuit. The ASP has a dynamic range of substantially better than 8-bits and provides for a wide range of signal sample rates (e.g., 1 to 40 MHz).

Abstract: A color camera apparatus comprises an image pickup element having a stripe/mosaic type color filter and photo-electrically converting an arriving optical image so as to obtain at least a signal including a brightness component and a color component multiplexed with each other. And, the apparatus comprises an A/D converter for digitizing above multiplexed signal, and a brightness signal processing circuit which separates the brightness component from the multiplexed signal and carries out an aperture correction by means of a delay element having a delay amount corresponding to two horizontal scanning period. And further, the apparatus comprises a color signal processing circuit which separates the color component from the multiplexed signal so as to obtain two line-sequential color difference components through a predetermined arithmetic procedure.