A machine readable binary code which is dynamically variable in size, format and density of information is provided. The binary code is formed as a matrix having a perimeter and data contained therein. The perimeter is provided with density indicia for indicating the density of data contained within the matrix. The perimeter is also provided with size indicia for indicating the size of the matrix. By utilizing the density indicia and size indicia, a scanning device is able to calculate the size and information density of the binary code.
This is a continuation of U.S. patent application Ser. No. 07/627,080, filed on Dec. 13, 1990, which is now U.S. Pat. No. 5,126,542; which is a continuation of U.S. patent application Ser. No. 07/513,362, filed Apr. 24, 1990 and is now U.S. Pat. No. 5,033,609; which is a continuation of U.S. patent application Ser. No. 07/190,205, filed May 5, 1988, which is now U.S. Pat. No. 4,939,354.
In order to reduce a two-dimensional data structure to a minimum number of bits, a two-dimensional surface pattern is provided, which can be used in particular for identifying an absolute position on the surface and which has a pattern which comprises a SYNC pattern, which is used for synchronization, and a position-dependent code PC(x, y), with the SYNC pattern being variable and being formed in accordance with an already known formation rule.
An exposure substrate of the invention is characterized in that at least one mark representing information related to the exposure substrate is provided on a part of the exposure substrate, and at least one of the marks contains information related to a mark readout operation. This information may include; the number, the position, or the order for reading the other marks to be read, or an end of information to be read. According to the present invention, information for other marks can be obtained from one mark, therefore, an optional number of marks can be read automatically.
A process and associated apparatus can automatically read a dot matrix code marking on an article even when the marking has been partly obscured or damaged in some way. The process comprises capturing a video image of the dot matrix code and correlating points on the captured image with a mask of expected dot appearance, using a known two-dimensional correlation technique. However, the correlation is performed in accordance with certain thresholding and mask adjustment criteria to improve read reliability and map the possible dot pattern in preparation for an attempt at reading the code. After automatically reorientating the map of possible dots to a read orientation if necessary, decoding of the pattern of possible dots is then attempted by comparing it with a datum grid representing rows and columns of valid dot matrix codes. The process can output a signal affirming that a valid code has been found.
A product with stored non-sequential data may be provided using a method that codes the data to a coding pattern using at least one sequence with symbols. The coding pattern may be configured such that an arbitrary subsequence of a predetermined magnitude of the sequence unambiguously defines the position of the subsequence in the sequence. The coding pattern may be reproduced on a product. An apparatus may be adapted to record and decode the coding pattern.
A product has a surface having with a position-coding pattern that codes a plurality of positions on the surface. The position-coding pattern includes a plurality of symbols each having at least two different values. Each position on the surface being coded with a plurality of symbols. Each symbol including a raster point in a raster extending over the surface, and at least one marking, the location of which in relation to the raster point specifies the value of the symbol. The markings can include information representing more than one spatial resolution level and varying between different markings. The position-coding pattern can be used in different contexts for position determination such as digitizing handwriting.
