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OCR ISBN Application Example
Product Reference Guide 8-15
OCR ISBN Application Example
One application of OCR is to read the ISBN characters typically
encoded using the OCR-A or OCR-B font. This is especially useful
when the ISBN number is not encoded in an EAN-13 bar code. The
following example shows how to configure the imager to read the ISBN
strings on books in Japan. After you have followed the steps below, you
will be able to scan the following ISBN number or the additional data
below it, depending on the line of text at which the imager is aimed.
1. Scan the
OCR-B On
bar code on
page 8-3
.
2. Program the user-defined variable “g” to comprise the ten digits
plus the dash:
0123456789-
3. In Japan, it is common for two fields to follow the ISBN number,
the three digit price field, and the four digit price field. The first
field typically starts with a “C” (uppercase c), followed by four dig-
its. The second field typically starts with a “P” or a yen symbol,
followed by three or four digits, followed by an “E.” Program the
user-defined variable “h” to comprise the “P” and the yen symbol
(represented by a backslash).
P\
4. Scan the symbol below to set up three templates to handle the
ISBN number, the three digit price field, and the four digit price
field.
5. Finally, set up the ISBN check digit, which is a special position-
weighted modulo 11 checksum. The imager automatically invokes
the ISBN checksum for template rows that are:
1.) at least fourteen characters long,
2.) whose first four characters are the letters “ISBN,”
3.) whose last character is a check character, and