Method and apparatus for determining and storing the contour course of a written symbol scanned column by column

Claim 3

The method of claim 1, wherein the step of determining the start and end of pairs of new contours is further defined as assigning a binary 1 to the symbol and a binary 0 to the symbol background, determining the function variable C as equal to -2 in the nth column at the start of a new inner contour and at the end of an outer contour where there is a phase change from a 1 to a 0, and determining the function variable C as equal to +1 in the nth column at the start of a new outer contour and at the end of an inner contour, whereby the unbalanced equations are met.

Claim 4

The method of claim 1, comprising the provision of upper and lower reference contours for the scanned symbol as permanent comparative contours.

Claim 5

The method of claim 1, comprising the steps of describing each contour by its elementary characteristics including ''''ascent positive'''' (SP) for an ascending contour course, ''''ascent negative'''' (SN) for a descending contour course, ''''horizontal'''' (HO) for a horizontal course, and ''''vertical'''' (VE) for a vertical course and digitizing the characteristics with combinations of the binary numbers 1 and 0.

Claim 6

The method of claim 4, comprising the step of determining from the ordinal differences the elementary characteristics of the symbol wherein a positive ordinate difference of an amount d between adjacent scanned columns corresponds to the elementary characteristic ''''ascent positive''''(SP) and to a (d - 1) sequence of the elementary characteristic ''''vertical'''' (VE), a negative ordinate difference of an amount d between adjacent scanned columns corresponds to the elementary characteristic ''''ascent negative'''' (SN) and to a (d - 1) sequence of the elementary characteristic ''''vertical'''' (VE), and an ordinal difference of zero corresponds to the elementary characteristic ''''horizontal'''' (HO).

Claim 7

The method of claim 1, comprising the step of directly addressing the contour memory with an address k of a contour kth line; transferring the data content of all memory lines having an address greater than (k - 2) into respective lines having address greater by two in response to the determination of new contours at addresses (k - 1) and k; transferring the data content of the concluded pair of lines corresponding to an end of a contour pair to a second contour memory; and transferring, after the last-named transfer, the data content of the first-mentioned contour memory having addresses higher than the concluded pair of lines to respective addresses which are smaller by two than that of the concluded pair.

Claim 8

Apparatus for determining and storing digital information representing a written symbol which consists of several contours which are scanned column-wise by a scanner which produces digital image signals including a first binary phase representing the symbol and a secondary binary signal representing the symbol background, comprising: first and second memory units for storing in sequence digital image signals representing ordinates for respective consecutively scanned columns; third and fourth memory units for storing data relating to starts and ends of contour pairs; first and second switch means respectively interposed between said first and third and said second and fourth memory units for transferring digital information therebetween; first and second comparator circuits connected to respective ones of said first and second switch means for comparing the data of adjacent columns; third and fourth switch means interposed between said first and second switch means and said third and fourth memory units respectively and respectively connected to and controlled by said first and second comparator circuits for separating the information; a difference circuit connected to said first and second switch means for deriving the difference values between contour ordinates of adjacent columns; a fifth memory unit for storing elemental characteristics of a symbol a fifth switch means connected between said difference circuit and said fifth memory unit and connected to and controlled by said first and second comparator circuits to transfer the data to said fifth memory unit; and a code converter interposed between said fifth switch means and said fifth memory unit for converting the difference values of the contour ordinates into coded form representing the elemental characteristics of the scanned symbol.

Claim 9

Apparatus for determining and storing digital information representing a written symbol which consists of several contours which are scanned column-wise by a scanner which produces digital image signals including a first binary phase representing the symbol and a secondary binary signal representing the symbol background, comprising: first and second memory units for storing in sequence digital image signals representing ordinates for respective consecutively scanned columns; third and fourth memory units for storing data relating to starts and ends of contour pairs; first and second switch means respectively interposed between said first and third and said second and fourth memory units for transferring digital information therebetween; first and second comparator circuits connected to respective ones of said first and second switch means for comparing the data of adjacent columns; third and fourth switch means interposed between said first and second switch means and said third and fourth memory units respectively and respectively connected to and controlled by said first and second comparator circuits for separating the information; a difference circuit connected to said first and second switch means for deriving the difference values between contour ordinates of adjacent columns; a fifth memory unit for storing elemental characteristics of a symbol a fifth switch means connected between said difference circuit and said fifth memory unit and connected to and controlled by said first and second comparator circuits to transfer the data to said fifth memory unit; and a code converter interposed between said fifth switch means and said fifth memory unit for converting the difference values of the contour ordinates into coded form representing the elemental characteristics of the scanned symbol.