Abstract: The subject matter of this specification can be implemented in, among other things, a method including identifying one or more blocks in an electronic image that depicts text characters. The method includes identifying one or more text blocks among the blocks that depict the text characters. The method includes identifying an average text contrast for each of the text blocks. The method includes identifying a type for each pixel in each of the text blocks based on the average text contrast. The method includes performing local adaptive filtering on a first neighborhood of pixels around each pixel in each of the text blocks to determine a brightness for the pixel based on the identified type. The method includes storing, in at least one memory, the electronic image including the determined brightness for each pixel in each of the text blocks.

Abstract: A tool information read/write device capable of being used in an automatic tool changer to which a conventional tool information read/write device cannot be applied, and a machine tool having the tool information read/write device. The read/write device has an arm section attached to a turret support part; a base section attached to the arm section; a slide section arranged on the base section so as to be linearly moved; a read/write head section attached to the slide section and configured to read/write information to a data carrier of a tool held by the turret; a drive section which drives the slide section so that the slide section reciprocates between a read/write position and an evacuation position; and a control section which controls the drive section in conjunction with a motion of the automatic tool changer.

Abstract: A method and apparatus for extraction of dots in an image are described. An image is binarized according to an initial intensity threshold to obtain an initial binary image including foreground and background pixels. Each foreground pixel has a foreground intensity value and each background pixel has a background intensity value. A set of blobs including foreground pixels is selected from the initial binary image to be part of a selected set of dots, where each blob from the set of blobs has characteristics of a dot. Responsive to determining that a successive binarization is to be performed, the following operations are repeated: (1) binarization of the image according to a successive intensity threshold (2) selection of a successive set of blobs, where each blob has characteristics of a dot. Responsive to determining that a successive binarization is not to be performed, the selected set of dots is output.

Abstract: A silicon halide, preferably SiCl.sub.4, is reacted with an excess of a base, e.g. a Lewis base or Bronsted base with steric hindrance group to produce an adduct. The adduct, which need not be separated, is treated with ammonia gas to produce the imide of silicon. A light organic solvent is used. The temperature used is -78.degree. C. to 100.degree. C. and the reaction is rapid.Byproduct ammonium halide is removed, and the imide is heated at 1000.degree. C. to 1600.degree. C. in an oven in an atmosphere containing nitrogen, to produce silicon nitride of good sintering characteristics and more than 70 wt % of which is of the .alpha.-crystal form.