Abstract: The image data (BDAT) associated with a respective document are transmitted to one of a plurality of recognition units for processing in a recognition process comprising a plurality of partial processes. The allocation of the processing jobs and the monitoring of the time cycles of the recognition processes is performed by a control unit (AU), by mean of which a timer is triggered to set the processing time of the recognition process in a recognition unit (e.g. RUn), the value of which is compared with an expected value for the processing time of the currently running partial process. The partial process results from the processing status of the recognition unit which is determined by status information and can be called at any time.

Abstract: A circuit arrangement is composed of a first adder whose first output is assigned to the digitized output signals of the photosensors and a second input connected to the outputs of a white level memory, and a second adder at whose input side the currently stored white level are linked with the correction signal and which reads the resultant signal back into the white level memory, the comparator following the first adder which, dependent upon the threshold level derived from maximum and average blackening values of the output signal of the first adder supplies a black signal or a white signal. A correction signal derived from a plurality of influencing variables serves for white level correction, the correction signal supplying a white level increment/decrement for delivery into the white level memory dependent on a carry signal that appears or, respectively, that does not appear at the first adder.

Abstract: An editing arrangement for character recognition has a binary coded character stored in a X/Y-addressable image signal memory from which signals are first read out column-by-column, whereby a first character shadow is formed from the result by projection of successive columns respectively comprising black points onto the character base line. The stored character pattern is then repeatedly read out in accord with a scanning at positive and/or negative oblique angles relative to the Y-axis until as minimum character shadow is produced. The scanned pattern yielding this minimum character shadow is then selected for further evaluation of the character.

Abstract: A level classifier comprises a group classifier and a plurality of sub-classifiers respectively assigned to a group. Each character is first assigned with the assistance of the group classifier to one of the n respective groups and then, to the specific group sub-classifier in which the actual character recognition occurs.

Abstract: A method and circuit for segmentation of characters from a serially-read character sequence scans the character sequence in a column-by-column format and intermediately stores portions or cut-outs of the scanned characters in the form of an image pattern matrix associated with each portion. The image patterns are thus offset by one column with respect to one another. For each image pattern, a coefficient memory stores several coefficients associated to the specific image pattern which are read out and summed to form a margin value which is associated with the average column of the individual image pattern matrix. A maximum value which occurs in the series of continuously formed margin values signifies a separating point for the associated column.

Abstract: For compensating tolerances within a photodiode matrix of a scanning unit, in a single scanning process, various momentary, column, displaced positions of a scanning pattern are compared with one another as current image signals. To this end, the plurality of black elements in an image signal to be first intermediately stored in a first image memory is counted in an image element counting device. When the current image signal reproduces a "fat" character, the white elements of the current image signal and of a correlated image pattern intermediately stored in a second image memory are disjunctively linked with one another in a switching device. Given "weak" characters, the black elements are employed. Insofar as the direction of the relative velocity between the scanning unit and a recording medium is not prescribed, a plurality of positions of the correlated image signal are to be employed for a comparison in a comparator circuit. This comparison yields the position with the best coincidence.

Abstract: An optical wand for automatically recognizing characters in a plurality of fonts incorporates a manually movable scanner incorporating a light source and a sensor array composed of a diode matrix. A first preprocessing unit is connected to receive the output from the scanner, and includes a correlation unit for buffering the data and apparatus for eliminating the effect of different characteristics of the individual photo diodes. The first preprocessing unit also includes a row tracking circuit and a segmentation circuit for presegmenting and for centering the character. Further segmentation, and filtering of the image is carried out by a second preprocessing unit which is decoupled from the first preprocessing unit, so that its operation is concurrent with that of the scanner. A recognition unit, decoupled from the second preprocessing unit, is connected thereto, and establishes individual values for the scanned characters by use of a quadratic polynomial classifier.