Abstract: The present invention provides a method and apparatus for reading bar codes having variable orientations on a substantially motionless medium. A portion of the surface of the medium having a bar code in a variable orientation is scanned using a light source and a photodetector receives the beam reflected from the surface and generates signals corresponding to the scanning lines. The signal corresponds to the scanning lines and has amplitude peaks corresponding to the intersection of the bars by the light beam. The amplitude peaks and position of the peaks on the scanning lines are recorded. The sum of the amplitude peaks is formed in the positions of the bars and deduced from the sums of the peaks amplitudes.

Abstract: Method for transforming a video type image having multiple levels of greys into a binary image, method wherein each pixel is either white or black. With each pixel of the initial image there is associated a partial image centered on said pixel and comprising a plurality of pixels in at least one dimension. If the histogram of the grey levels of said partial image is considered as bimodal (D>E), a threshold (S) median with respect to said histogram is selected. If the histogram is considered as monomodal (D<e), a threshold (S) outside said histogram is selected, the position of this threshold with respect to the histogram being determined by comparison of the latter with a preset mean background value (FM). Application to telecopy, electronic storage of documents and drawings, preprocessing in order to facilitate the reading of handwritten messages or recognition of patterns in general.

Abstract: The invention relates to a method and to a device for determining the number of people to be found in a determined space, by means of a strip (14) of photodetectors (16) on which an objective lens (10) forms a linear image of a space including objects or people (12). The signals successively produced by the photodetectors (16) are compared by a microprocessor (22) in order to show up movement of people and to deduce the number of people present therefrom.The invention is applicable to performing surveillance of premises and to performing automatic television audience surveys.