Abstract: A method of generating a bitmap representative of an original image. The method comprises (1) scanning the original image to generate a greyscale pixel map; (2) interpolating and rotating the greyscale pixel map to generate a higher resolution greyscale pixel map; and (3) converting the higher resolution greyscale pixel map into the bitmap. The greyscale pixel map is converted into the bitmap by (I) ranking each greyscale pixel value against the greyscale pixel values of a neighborhood of adjacent pixel locations; (ii) determining a desired number of black binary pixels (B_Pc) in the neighborhood; (iii) comparing the rank of the greyscale pixel with the desired number of black binary pixels; and (iv) assigning a black binary pixel value to the pixel location when the comparison carried out in step (iii) satisfies a predetermined condition.

Abstract: A rotatable mirror assembly comprises a rotatably mounted support (1); and a mirror (7) mounted to the support for rotation therewith. The mirror (7) is mounted at a position (5) laterally offset from the axis (6) of rotation of the support, the mirror being spaced from the remainder of the support to allow the mirror to distort when it is rotated.

Abstract: Image viewing apparatus comprises a transparent platen on which an image to be scanned can be positioned. A scanning system support is movable alongside the platen. A light source illuminates the platen from the same side as the scanning system support. A light diffuser can be moved between a first position in which it is located between the light source and the platen whereby light from the light source is diffused across the platen, and a second position in which the light diffuser is positioned so as not to impede a scanning system on the support from viewing an image on the platen.

Abstract: A method of monitoring distortion in a reflective surface of a spinning mirror, the method being constituted by (1) spinning the mirror; (2) directing a beam of radiation onto the reflective surface of the spinning mirror to generate a reflected beam; (3) positioning a radiation detector in the path of the reflected beam, whereby the radiation detector generates an electrical signal responsive to the shape of the reflected beam; and (4) monitoring the shape of the reflected beam by monitoring the electrical signal generated by the radiation detector.

Abstract: Apparatus for scanning a light beam over an image surface includes a carriage assembly, including structure for directing a light beam over the image surface. A pad assembly, which is rotatably mounted to the carriage assembly, includes a pad surface. A slideway engages the pad surface to support the carriage. In use, a drive force is applied to the pad assembly so that the pad surface slides along the slideway in a given direction of movement as the light beam scans the image surface. A rotational force is applied to the pad assembly to cause the pad surface to pitch back on the slideway relative to the given direction of movement.

Abstract: A method of generating image data comprising digital pixel data representative of one or more images on an input scanner support.In a first step the support is scanned to generate support image data at a first resolution comprising digital pixel data representative of the support and image.In a second step support image data at a second resolution is generated from the support image data at a first resolution. In a third step the boundary of an image is determined by performing a predetermined boundary determining algorithm on the support image data at the second resolution.In a fourth step, the image data is extracted from the support image data at the first resolution by extracting pixel data within the boundary of the image determined in the third step.

Abstract: A method of input scanning an image using a detector comprising an array of radiation sensors, the method comprising1) exposing the radiation sensors to radiation from the image over a plurality of sampling periods, and for each respective sampling period:2) obtaining a single data value from each radiation sensor;3) summing the data values obtained during the sampling period;4) determining a peripheral response value in accordance with the sum obtained in step 3), wherein the peripheral response value for each sampling period is determined independently of the peripheral response values for the other sampling periods; and5) modifying the data values in accordance with the peripheral response value obtained in step 4).

Abstract: A method and apparatus for generating a digital representation of an image. The apparatus includes a scanning device for scanning the image to generate digital data defining the colour content of pixels of the image. An input profile generator is provided for generating an input profile defining the NTF of the scanning device.

Abstract: Radiation beam scanning apparatus comprises a rotatable reflector for causing an incident radiation beam to undergo a scanning movement; and a compensating device on to which the radiation beam impinges before reaching the rotating reflector. The compensating device modifies the optical path of circumferentially spaced portions of the beam upstream of the reflector, in phase with the rotation of the reflector, so as to compensate for distortions in the reflected beam introduced by the reflector.

Abstract: A method and apparatus for enhancing an image defined by electrical signals representing the colour component content of each pixel of a relatively high resolution version of the image. The apparatus comprises a first store for storing the high resolution version of the image; a second store for storing fringe values; and a processor coupled with the first and second stores. The processor is adapted to determine for each colour component of each pixel in the first store a fringe value by determining the difference between the component values at the high resolution and at a lower resolution and to store the fringe values in the second store; to determine for each pixel the length of a vector whose components are defined by values related to the fringe values of that pixel; and to modify each original colour component value in the first store by an amount related to the respective fringe value determined in accordance with the relationship of the vector length with a threshold.