Abstract: Imagery data is compressed by subdividing the data into a plurality of blocks. Each block is encoded into a bit map and a pair of threshold values. The bit map provides an array of binary encoded imagery data-representative vector combinations. A vector combination is subdivided into a set of adjacent sub-blocks, each which is examined to determine whether or not it is associated with a prescribed attribute of the image. If the vector is associated with a prescribed attribute, a code representative of that attribute is generated. If the vector is not associated with a prescribed attribute of the image, prescribed portions of the vector are inverted to derive modified vectors that are associated with prescribed image attributes. For each such modified vector a corresponding code is generated. Using each of these corresponding codes, image data is effectively reconstructed and then compared with the original image data.

Abstract: A method and apparatus for processing a screened separation comprises an analyze scanner for scanning the separation at a resolution higher than the screen ruling to generate a binary value for each high resolution pixel of the separation; a processor for generating signals representing single values for respective blocks of the high resolution pixels from the binary data in the blocks; and a descreening system to which the signals from the processor are fed, the descreening system generating signals representing a descreened version of the original separation.

Abstract: An object such as a stimulable phosphor sheet on which image information is recorded is scanned by a light beam such as a laser beam, and light bearing the image information from the object is photoelectrically detected to produce an image signal representing the image information. A monitor signal representing the light beam is divided into a high-frequency component and a low-frequency component. A corrective signal is produced multiplying a ratio of the high-frequency component to the low-frequency component by a constant. The corrective signal is then subtracted from the image signal.

Abstract: A picture element data generating method comprises the steps of extracting a noticeable pixel and a plurality of reference pixels from image data, the reference pixels being adjacent to the noticeable pixel; and generating a pixel positioned within a minimum polygon which is formed so as to include the noticeable pixel and the reference pixels as vertexes thereof or include the reference pixels as vertexes and the noticeable pixel on a side thereof. A level of the pixel being calculated by use of levels of the noticeable and reference pixels which are weighed.

Abstract: An optimal image-quality selection apparatus calculates a ratio of the number of graphic blocks having a predetermined size to the number of all graphic blocks of an image having two or more depth levels of color and selects an image having a largest one of the ratios as an image of optimal quality.

Abstract: A source facsimile machine has a function of ending a retransmission process when image data related to error-free frames cannot be received at a destination facsimile machine. The destination facsimile detects an error in each of lines of the frame and records the error-free lines. Hence, even when errors exist in the received frames, it is still possible to record the received image by recording the error-free lines. In other words, the detination facsimile can record the received image with a minimum dropout of image information caused by the errors in the received frames.

Abstract: An adaptive image acquisition system employing a hand-held optical scanner or camera is disclosed. The system includes an adaptive camera exposure control system to adjust the camera exposure time to the media's reflectivity characteristics. The system assembles a "film-strip" of images from compressed video data, wherein redundant image data appearing in successive image frames has been removed. The system employs a correlation process between successive frames to identify the redundant frame information and determine the camera velocity. By adapting the correlation process to the velocity of the camera, the effects of variations in the velocity may be substantially eliminated.

Abstract: A signal combining circuit for adaptively combining first and second signals includes a comparator to develop a control signal to indicate when the combination of the first and second signals will have an amplitude exceeding a predetermined amplitude in one polarity sense. In the absence of the control signal the first and second signals are combined. On the occurrence of the control signal the first signal is combined with a further signal related to the first signal and a reference value.

Abstract: An image editing system for a digital copier, facsimile apparatus or similar image recoding apparatus having a capability for marking a particular area of a document image. The system allows a document image to be marked not only in a square area but also in an area which is defined by any desired slant line or lines.

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.

Abstract: Method and apparatus for the selective scaling, such as magnification and reduction, of video images stored as collections of image pels in a video memory. A lookup table is provided for determination of the values of the scaled image pels. A framing matrix of unscaled image pels is established for each scaled image pel. The framing matrix for the scaled image pels determines the outputs read out of the lookup table, and derivatively, determines the values of the scaled image pels. The scaled image pels are stored in the video memory for subsequent display or processing.

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.

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: 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 system for self-aligning a raster input scanner in the slow scan direction where, at start of scan, a target having a variable density image is scanned first until a preset target image line is obtained and the position of the scan carriage registered; then from the registered position, the platen is scanned through a predetermined number of scan lines; following this, the carriage is reversed and returned the same number of scan lines where the target is again scanned and the target image line obtained compared with the previous target image line to determined if a valid scan cycle has taken place.

Abstract: Apparatus and method for discriminating between regions of text and continuous tone areas of mixed format documents and for selecting print/no-print decisions to be made by either an image processing algorithm optimized for text or an image processing algorithm optimized for continuous tone. A video signal of digital values indicative of pixels representing the image content of the document is applied to a two-level comparator to produce a preliminary text mode or continuous tone mode decision. A continuous tone preliminary decision is changed to a text decision if the pixel of interest is within a predetermined distance of a text pixel.

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: Test image information is recorded on a test recording medium and the test recording medium is scanned with a light beam to produce an image signal in each of two modes in which the test recording medium is oriented such that a prescribed line on the test recording medium extends in a main scanning direction and an auxiliary scanning direction substantially normal to the main scanning direction respectively in the two modes. A signal level distribution A(x) is determined along the prescribed line of a signal indicative of a logarithmic function of an output signal from a light detector when the prescribed line extends along the main scanning direction, and a signal level distribution B(x) along the prescribed line of a signal indicative of a logarithmic function of an output signal from the light detector when the prescribed line extends along the auxiliary scanning direction (x indicates a pixel position on the prescribed line).

Abstract: A contact-type image sensor has amorphous semiconductor photoconductive cells formed on a substrate and divided into cell units each consisting of a number of cells. A drive signal generator is connected to the cells to sequentially select the cell units, thereby sequentially activating the cells of any selected unit. A signal readout circuit is connected to the cell units, for generating a series of pixel signals from pixel currents sequentially supplied from the cells of any selected unit. The signal readout circuit includes a common signal output line connected to the cell units, and a capacitor component connected to this output line, for sequentially accumulating the pixel currents. The capacitor component is not a discrete element, but is equivalent to the sum of the stray capacitance components inherently present in the image sensor, such as parasitic capacitance components and the coupling capacitance between the output line and the ground.

Abstract: An image display apparatus includes a conversion circuit which makes 1-bit information in display memory correspondence to a plurality of dot data on the display screen, so that more sophisticated image information than the ability of a display device is expanded into a bright/dark dot pattern. The apparatus enables an application display program oriented to a higher-graded display device to be displayed in a pseudo sense on a lower-graded display device.

Abstract: A recording signal generating circuit for printing comprises a shift register for sequentially storing image information on a predetermined number of consecutive pixels. A recording signal pulse width setting circuit normally sets a pulse width of a recording signal for each of a pixel information to a standard pulse width. The setting circuit sets a pulse width of the recording signal for a pixel positioned at the center of the shift register (a pixel of interest) to a wider pulse width when an isolated black pixel pattern is detected. Alternatively the setting circuit sets a pulse width of the recording signal for one of the pixels just preceding and following the pixel of interest to a narrower pulse width when an isolated white pixel pattern is detected.

Abstract: A method and image processing system is for reconstruction of an input image. The method for reconstruction of an input image includes a step of inputting image data (for example, densities) of at least two pixels nearest to a position of an additional pixel to be added to the input image and those of neighbor pixels located on extension lines of segments drawn between the position of the additional pixel and that of each of the nearest pixels of which the image data were inputted, and a step of estimating the value of the image data of the additional pixel on the basis of the inputted image data of at least two pair of the nearest and corresponding neighbor pixels by using an improved and simple algorithm which is newly proposed herein and called "linear extrapolation and average method".

Abstract: Apparatus, and an accompanying method, for use in an image enhancement system for providing background and noise values which, in many instances, are more representative of background and noise levels occurring in a scanned video image than those values previously obtainable in the art. This apparatus, which in its general form can be used to implement both a noise tracking circuit and/or a background tracking circuit, includes a two-dimensional non-linear, preferably infinite impulse response, filter that provides an output filtered value based upon the value of an incoming pixel situated on a current scan line and to first and second prior output values. The first prior output value is the output filtered value that is associated with a pixel located on a pre-determined one of a plurality of prior scan lines and situated to the right of the current pixel.

Abstract: Apparatus for reproducing a scanned picture with sharpness emphasized. A scanner is provided for scanning a picture to be reproduced in two directions perpendicular to one another and for generating and recording signals representing the scanned picture. There is a sharpness emphasizing device for summing and averaging a plurality of picture element signals aligned in one of the scanning directions in the vicinity of a scanning point in the picture being scanned and recorded to generate values and then summing and averaging a plurality of the resulting summed and averages picture signals aligned in the other scanning direction in the vicinity of said scanning point to generate further values and then producing a recording signal equal to S+k(S-U), where k is a constant chosen to enhance a particular characteristic of the scanned picture, S is the sharp signal component at said scanning point and U is a generated unsharp signal.