Abstract: An object which is sequentially illuminated by light having wavelengths different for each of several fields is imaged using an X-Y addressed solid state imaging device. The photoelectrically converted signals are read out from the solid state imaging device by the application of drive signals, the read-out being performed without providing a period during which light illumination is suspended. The color mixture caused in accordance with the read-out timing is corrected by using weighting coefficients so as to produce predetermined color video signals.
Abstract: A high resolution image is decomposed into a low resolution replica and into corresponding supplemental information for facsimile transmission to a remote location. The low resolution replica is generated by replacing a super pixel (picture element) including a plurality of high resolution image pixels with a single low resolution pixel and corresponding supplemental information, if any is required. The pixels of the low resolution replica are chosen such that all supplemental information required to convert the low resolution replica back to the original high resolution image is located at the "edges " of the low resolution replica. Thus, if a low resolution pixel is at an edge in the low resolution pixel is at an edge in the low resolution replica, supplemental information is generated in accordance with prescribed criteria.
January 22, 1988
Date of Patent:
October 10, 1989
American Telephone and Telegraph Company, AT&T Bell Laboratories
Abstract: A high resolution image is decomposed to a basic lower resolution replica and a plurality of supplemental information fields for use in a progressive high resolution image facsimile transmission system. The basic lower resolution replica is generated by successive decompositions of the original image into a plurality of intermediate lower resolution replicas and corresponding supplemental information fields by employing a so-called edge decomposition technique. The supplemental information fields are required in a receiver to upgrade the basic lower resolution replica toward the original high resolution replica.
January 22, 1988
Date of Patent:
September 26, 1989
American Telephone and Telegraph Company, AT&T Bell Laboratories
Christodoulos Chamzas, Donald L. Duttweiler
Abstract: Transition-encoded information for a single scan line of a font image consists of flags at the addresses of all points of transition upon the scan line from black to white, and from white to black, in order to generate one scan line of the font image. This information is produced, scan line by scan line, in a system receiving the vertical position, the horizontal position, and a starting address within a font memory whereat a run-length-encoded description of a particular character font is stored. This information is developed by adding, in an adder, the initial horizontal displacement plus, in a cumulative fashion, the run-length-encoded font information for each character which appears, in some portion, upon an individual scan line. The transition-encoded information is used to control pixel by pixel image generation in an image generator equivalently to full bit-mapped control but with lower cost, higher speed of conversion, and greater flexibility in the images generated.
Abstract: A color display device particularly adapted for use in flat panel applications provides a bright picture with high saturation and excellent color reproduction. The color display device includes a light shutter mechanism which controls the amount of light passing therethrough. Color filters of different colors are disposed adjacent to the light shutter mechanism and include a plurality of color elements. Each color filter has a peak at the transmittance spectrum thereof. A light source illuminates the light shutter mechanism with the light source having peaks in a luminance spectrum adjusted to correspond to the peaks of the transmittance spectrum of each color filter.
Abstract: An image reading device having a document handling system is suitable utilized on a modified standard office copier as electronic copying machine. In particular, the document presser plate is composed of a presser plate which is provided on the cabinet of the device. The document presser plate is held selectively over the exposure glass surface in two or more positions and used as the document feed tray in automatic document feed. When using this invention, the document presser plate functions as a document feed tray and a document dispense tray, there is no requirement for special feed and dispense trays. A compact and light-weight unit can therefore be achieved.
Abstract: A multi-gradation image signal obtained by multi-gradationization of a signal obtained by reading through a CCD an original having a half tone is supplied to an unsharp signal producing part, which in turn outputs an unsharp signal produced from the multi-gradation image signal and the multi-gradation image signal itself. A comparator discriminates a shadow portion of the original by comparing the multi-gradation image signal with a reference value. As a result, a signal which is unsharp in the shadow portion of the original is produced from the multi-gradation image signal and the unsharp signal.
Abstract: Apparatus and an accompanying method are disclosed herein for improving the compressibility of an enhanced digital video signal, illustratively comprised of a serial bit stream, such as that generated by scanning a video image produced, for example, by a microfilm scanner. Specifically, whenever a video transition occurs in the a stream of incoming pixels, this apparatus momentarily varies a threshold level, in an appropriate direction, during the transition in order to reduce the noise content in threshold pixel values and thereby enhance the compressibility of these pixels.
Abstract: A system for analyzing and reproducing the color information of an original picture is disclosed. A transmitting device is provided with a plurality of frame memories each of which stores a color image signal corresponding to a particular color component of the original. The time axis of the color image signals is changed by controlling the store speeds and the read out speeds of the memories. The color signals are read out and transmitted in a frame-sequential manner. At the time of transmission of each frame, a start signal is added to each color signal for use in the receiver of the system. At the receiver, a storage device is provided. The latter includes a plurality of memories each for storing a different one of the transmitted color signals. The storage device is responsive to the start signals in the color signals and storage in the memories is carried out in response to these start signals.
Abstract: A color contrast correction system for video images obtained from color film provides signals representative of the extent of exposure of the color film and then provides for adjustment of the gamma of the respective RGB signals to correct for over or under exposure of the film.
Abstract: A signal processing device comprises buffer memory means for outputting a coded signal in parallel by a signal of predetermined bits, shifting means for shifting the coded signal so that the head bit of the coded signal become the head of the outputted signal, decoding memory means for decoding the coded signal to a run length signal having information of the run length of the coded signal, and outputting a shifting signal designating a bit number of the coded signal corresponding to the number to be shifted, into said shifting means. Accordingly, said signal processing device enables to decode a coded signal at a higher speed than a conventional image signal processing device and to output an image signal into an electrophotographic printer or a CRT display, synchronizing with a processing speed of the electrophotographic printer or a sub scanning speed of the CRT display.
Abstract: An image processing apparatus comprises an input device for entering an image input signal and a detector for detecting a characteristic, such as contrast, gradation or the like, of the input signal. A converter converts that characteristic of the input signal, in response to the detected characteristic. The converter includes a conversion table addressably by the input signal, and preferably includes a calculator for calculating the conversion table in response to the detected characteristic. Preferably, the converter carries out logarithmic conversion of the input signal. Several such tables may be provided, an appropriate one being selected depending upon input conditions. One or more such tables may have variable contents determined in response to the detected characteristic of the input signal. The converters may each comprise one or more memories storing a respective conversion table addressable by the input signal.
Abstract: A color correcting circuit for thermal printer comprises a first circuit for obtaining a first degree correction operation result, a second circuit for obtaining a second degree correction operation result, and a difference limiting circuit for selectively outputting a correction data. The first degree correction operation makes the relationship between the density of an input image and the density of an output image linear for each primary color. The second degree correction operation reduces a difference between the density of the input image and the density of the output image by use of the method of least squares for each primary color.
Abstract: A color facsimile machine includes a three-color plotter for recording image information received from a transmitter. Even if the transmitter is a monochroic facsimile machine so that image information received is monochroic, the present color facsimile machine records the image information with a preselected color. In addition, if image information received is multi-color image information, then the present color facsimile machine can record the image information in accordance with the color of an original image. Besides, it may also be so set to record any accompanying information, such as identification of the transmitter and data or time of reception, with a preselected color.
Abstract: The present invention relates to a method and an apparatus for driving image pick-up tubes in, particular, a color television camera or the like having more than one image pick-up tube and in particular to a method and an apparatus for driving image pick-up tubes in which the potentials of the cathode electrodes of the respective image pick-up tubes are set to the same common potential, the potential of the target electrode of at least one of the image pick-up tubes is set substantially to earth potential, target drive potentials are individually applied to the target electrodes of the other image pick-up tubes, and the target potential of each image pick-up tube is set to a value near the earth potential, so that a high S/N ratio is obtained. The driving appartatus can be miniaturized and easily driven. According to the invention, a capacitor, such as a chip capcitor or the like, with a low withstanding voltage can be used in a first-stage amplifier to amplify the video signal from the target electrode.
Abstract: An image processing method and system in which an original image is read line by line by means of a plurality of image sensors to produce image data segments corresponding to respective segments of a line read by each of the image sensors. The image data segments produced by the image sensors are processed to produce a second plurality of image data segments, which are subsequently subjected to a predetermined image processing operation. The second plurality of image data segments are combined, either before or after being subjected to image processing, into a line of image data for each original image line.
Abstract: A color image pickup apparatus in which a luminance signal is formed by repeatedly switching, one by one, red, green and blue color signals separated by color separation circuits from a dot sequential output of a color CCD image pickup element and balanced by a white balance control circuit. The red, green and blue color signals are combined in a luminance signal processing circuit. The apparatus further comprises a first gain control circuit for increasing the gain of the luminance signal processing circuit in order to increase the sensitivity of the apparatus. Also a second gain control circuit is provided for decreasing the signal level of the blue color signal supplied to the luminance signal processing circuit when the gain of the luminance signal processing circuit is increased. Circuitry may be included for processing the color temperature and the brightness of the object so as to control the balance of the plural different color signals.
Abstract: An image signal processing apparatus may include a line sensor for photoelectrically reading an original image and outputting an image signal, a rotary encoder for setting reproduction magnifications of the original image, an edge emphasis circuit for performing edge emphasis processing for the image signal output from the line sensor, and W- and R-address counters and first and second clock cotnrol signals, all of which cooperate to control a degree of edge emphasis performed by the edge emphasis circuit in accordance with the reproduction magnification set by the rotary encoder. The magnification can preferably be set independently for the main scanning and the sub-scanning directions. A correction signal is used in the edge emphasis processing, and is preferably formed on the basis of image signals of pixels near the particular pixel of interest. The image signal may also be smoothed after edge emphasis.
Abstract: A color filter has a plurality of succesively arranged recurrent groups of different color stripes. An image pickup tube has a photoelectrical conversion target exposed to light passing through the color filter and an index signal generation pattern. The image pickup tube outputs a signal containing a color signal component determined by a carrier which is modulated with the individual color stripes of each recurrent group of the color filter. The output signal from the image pickup tube also contains an index signal component which depends on the index pattern. A first memory holds at least part of the index signal component. The index signal component held by the memory is periodically updated. A second memory holds a portion of the output signal from the image pickup tube which was obtained under conditions where a predetermined color light illuminates the photoelectrical conversion target via the color filter.
Abstract: In a television camera having a color resolving prism system for forming monochromatic images on the image pickup surfaces of a plurality of image pickup devices by an objective lens the color resolving prism system has first, second, third and fourth prisms as is named in the order from a side of the objective lens along the optic axis of the objective lens, the first and second prisms, with their refracting angles opening in opposite directions, are edisposed with an air layer interposed therebetween or are joined together with a dichroic layer interposed therebetween, the second and third prisms are disposed with an air layer interposed therebetween, the third and fourth prisms are joined together with a second dichroic layer interposed therebetween, and the values of the refracting angles of the first .theta..sub.10 or .theta..sub.21), second .theta..sub.10 +.theta..sub.11 or .theta..sub.22, third .theta..sub.23 and fourth .theta..sub.