Method and apparatus for encoding and decoding single byte characters in double byte character set of machine-readable symbologies, such as bar code symbologies

• US 6,024,289 A
• Filed: 01/22/1998
• Issued: 02/15/2000
• Est. Priority Date: 01/22/1998
• Status: Expired due to Term

• Current Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Original Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Inventors: Ackley, H. Sprague
• Primary Examiner(s): LE, THIEN MINH
• Application Number:
  US08/999,613
• Time in Patent Office: 754 Days
• Field of Search: 235/462.01, 235/462.02-462.15, 235/462.25, 235/462.24, 235/472.01, 235/494, 235/454
• US Class Current: 235/494
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1491 the method including a reconstruction step, e.g. stitching two pieces of bar code together to derive the full bar code

Abstract

A method and apparatus efficiently encodes a stream of character codes corresponding to the data characters from a first set of data characters, a number of the data characters also being contained in a second set of data characters which is a subset of the first set of data characters. The method and apparatus according to one exemplary embodiment parses the data stream to remove therefrom all character codes corresponding to data character contained in the second set of data characters. Each of the character codes in the parsed data stream is converted according to a first translation into a first defined number of symbol values and each of the character codes parsed from the data stream is converted according to a second translation into a second number of symbol values. Each of the symbol values corresponds to a symbol element. A method and apparatus also decodes a stream of symbol values, corresponding to a set of efficiently encoded symbol characters, to produce a string of character codes. The decoding method and apparatus receives the data stream, parses the data stream to separate symbol values corresponding to data characters encoded in a single symbol character from symbol values corresponding to data characters encoded in more than one symbol character. Each of the symbol values parsed from the data stream is decoded according to a first translation into a character code. Each set of the symbol values remaining in the parsed data stream corresponding to a single data character is decoded according to a second translation into a corresponding character code.

Claims

1. A method of encoding a data string into a bar code symbol, the data string comprising a plurality of data characters, the data characters selected from a double byte character set of human readable characters, a number of the data characters also being contained in a single byte character set which is a subset of the double byte character set, the method comprising the steps of:

determining a plurality of character codes corresponding to the plurality of data characters, the character codes selected from a first set of character codes, the first set of character codes being mapped to the first set of data characters;

parsing the data string to separate the double byte character codes of characters from the single byte character set from the data string;

converting the double byte character codes in the parsed data string into double byte symbol values;

converting the double byte character codes parsed from the data string into single byte symbol values; and

outputting the double byte symbol values and the single byte symbol values to form the bar code symbol.

2. The method of claim 1, wherein the step of outputting the symbol values includes the steps of:

calculating a set of counts corresponding to the symbol values; and

operating a printer based on the set of counts to print the symbol.

3. The method of claim 1, further comprising the steps of:

receiving a plurality of scan codes;

parsing the plurality of scan codes; and

determining a plurality of character codes based on the parsed scan codes.

4. The method of claim 1, wherein the double byte character set is GB and the single byte character set is ASCII, and wherein the step of parsing comprises the step of examining the data values for the string equal to Hexadecimal 2A.

5. The method of claim 1, wherein the step of parsing comprises the step of examining a predefined memory location for a predefined value.

6. A method of encoding a data string into an optical symbol, the encoding method comprising the steps of:

receiving the data string comprising a plurality of double byte character codes, the double byte character codes corresponding to data characters from a double byte character set, a number of the data characters from the double byte character set also belonging to a single byte character set, the optical symbol comprising a number of symbol characters;

parsing the data string to separate the double byte character codes of data characters in the single byte character set from the data string;

converting each of the double byte character codes parsed from the data string into one symbol value;

converting each of the double byte character codes in the parsed data string into a combination of symbol values; and

outputting the symbol values.

7. The method of claim 6, further comprising the steps of:

receiving a string comprising a plurality of data characters, the data characters selected from the double byte character set and the single byte character set;

determining a plurality of character codes corresponding to the plurality of data characters, the character codes selected from the set of double byte character codes; and

outputting the plurality of double byte character codes as the data string.

8. The method of claim 6, wherein the step of outputting the double byte symbol values includes the steps of:

calculating a set of counts corresponding to the double byte symbol values; and

operating a printer based on the set of counts to print the symbol.

9. The method of claim 6, further comprising the steps of:

receiving a plurality of scan codes;

parsing the plurality of scan codes; and

determining the plurality of double byte character codes based on the parsed scan codes.

10. The method of claim 6, wherein the double byte character set is GB and the is single byte character set is ASCII and wherein the step of parsing comprises the step of examining the character codes for a string equal to Hexadecimal 2A.

11. The method of claim 6, wherein the step of parsing comprises the step of examining a predefined memory location for a predefined value.

12. A method of encoding a data string into a symbol, the method of encoding comprising the steps of:

receiving the data string comprising a plurality of character codes selected from a first set of character codes, wherein the first set of character codes map to a first set of data characters, and wherein a second set of data characters form a subset of the data characters in the first set of data characters;

converting each of the plurality of character codes corresponding to data characters contained only in the second set of data characters into a first defined number of symbol values;

converting each of the plurality of character codes corresponding to characters in both the first and the second sets of data characters into a second defined number of symbol values, the second defined number of symbol values being greater than the first defined number of symbol values; and

outputting the converted symbol values.

13. The method of claim 12 wherein the first defined number is one and the second defined number is three.

14. The method of claim 12, further comprising the steps of:

receiving a string comprising a plurality of data characters, the data characters selected from the first set of data characters and the second set of data characters;

determining the plurality of character codes corresponding to the plurality of data characters, the character codes selected from the first set of character codes; and

outputting the plurality of character codes as the data string.

15. The method of claim 12, wherein the step of outputting the symbol values includes the steps of:

calculating a set of counts corresponding to the symbol values; and

operating a printer based on the set of counts to print the symbol.

16. The method of claim 12, further comprising the step of:

printing symbols corresponding to the converted symbol values.

17. The method of claim 12, further comprising the steps of:

receiving a plurality of scan codes;

parsing the plurality of scan codes; and

determining a plurality of character codes based on the parsed scan codes.

18. The method of claim 12, further comprising the step of parsing the data string to separate the character codes corresponding to data characters only included in the second set of data characters from the character codes corresponding to data characters include in both the first and the second sets of data characters.

19. The method of claim 12, wherein the first set of data characters is GB and the second set of data characters is ASCII, and wherein the step of parsing comprises the step of examining the data values for a string equal to Hexadecimal 2A.

20. The method of claim 12, wherein the step of parsing comprises the step of examining a predefined memory location for a predefined value.

21. A method of encoding a data string into a symbol, the method of encoding comprising the steps of:

receiving the data string comprising a plurality of character codes selected from a first set of character codes, wherein the first set of character codes map to a first set of data characters, and wherein a second set of data characters form a subset of the data characters in the first set of data characters;

parsing the data string to remove all character codes corresponding to the data characters contained in the second set of data characters;

converting each of the character codes in the parsed data string into a first defined number of symbol values, and converting the character codes parsed from the data string into a second defined number of symbol values, where the second defined number of symbol values is greater than the first defined number of symbol values; and

outputting the converted symbol values corresponding to the parsed character codes and the converted symbol values corresponding to the parsed data string.

22. The method of claim 21, wherein the first defined number is one and the second defined number is three.

23. The method of claim 21, further comprising the steps of:

receiving a string comprising a plurality of data characters, the data characters selected from the first set of data characters and the second set of data characters;

determining a plurality of character codes corresponding to the plurality of data characters, the character codes selected from the first set of character codes; and

outputting the plurality of character codes as the data string.

24. The method of claim 21, wherein the step of outputting the symbol values includes the steps of:

calculating a set of counts corresponding to the symbol values; and

operating a printer based on the set of counts to print the symbol.

25. The method of claim 21, further comprising the step of:

printing symbols corresponding to the converted symbol values.

26. The method of claim 21, further comprising the steps of:

receiving a plurality of scan codes;

parsing the plurality of scan codes; and

determining a plurality of character codes based on the parsed scan codes.

27. The method of claim 21, wherein first set of data characters is GB and the second set of data character is ASCII, and wherein the step of parsing comprises the step of examining the data values for the string equal to Hexadecimal 2A.

28. The method of claim 21, wherein the step of parsing comprises the step of examining a predefined memory location for a predefined value.

29. A method of decoding a string of symbol values, the method comprising the steps of:

receiving the string of symbol values selected from a set of symbol values, wherein the set of symbol values map to a set of data characters comprising a set of double byte data characters and a subset of single byte data characters;

parsing the string to separate the symbol values corresponding to the single byte characters from the symbol values corresponding to the double byte characters;

converting each pair of the symbol values corresponding to a double byte character into one character code from a first set of character codes, and converting each of the symbol values corresponding to a single byte character into one character code from the first set of character codes; and

assembling the character codes into a string of character codes.

30. The method of claim 29, further comprising the steps of:

imaging a symbol, the symbol comprising a plurality of symbol characters;

converting the imaged symbol into a data string comprising a plurality of symbol values, the symbol values corresponding to the symbol characters; and

outputting the plurality of symbol values as the data string of symbol values.

31. The method of claim 29, wherein the step of converting each of the symbol values corresponding to a single byte character into one character code from the first set of character codes comprises the steps of:

converting the single byte symbol value into a single byte character code; and

converting the single byte character code into the double byte character code.

32. The method of claim 29, further comprising the steps of:

imaging a symbol to produce a signal representative of each of a plurality of symbol characters comprising the symbol;

analyzing the signal to identify the symbol characters; and

converting each of the symbol characters into a corresponding symbol value selected from the set of symbol values.

33. A method of decoding a data string, the decoding method comprising the steps of:

receiving the data string comprising a plurality of symbol values selected from a first set of symbol values, wherein each of the symbol values in the first set of symbol values map to a first set of data characters including at least one shift data character;

identifying any symbol values corresponding to the shift data characters;

converting each identified symbol value and a defined number of subsequent symbol values into one character code, and converting each of the unconverted symbol values into one character code, the character codes selected from a first set of character codes; and

assembling the character codes into a data string.

34. The method of claim 33, further comprising the steps of:

imaging a symbol, the symbol comprising a plurality of symbol characters;

converting the imaged symbol into a data string comprising the plurality of symbol values, the symbol values corresponding to the symbol characters; and

outputting the data string of symbol values.

35. The method of claim 33, wherein the step of converting each of the unconverted symbol values comprises the steps of:

converting each of the single byte symbol values into a single byte character code; and

converting each of the single byte character codes into the double byte character code.

36. The method of claim 33, further comprising the steps of:

imaging a symbol to produce a signal representative of each of a plurality of symbol characters comprising the symbol;

analyzing the signal to identify the symbol characters; and

converting each of the symbol characters into a corresponding symbol value selected from the set of symbol values.

37. A method of decoding a data string, the decoding method comprising the steps of:

receiving the data string comprising a plurality of symbol values selected from a first set of symbol values, wherein each of the symbol values in the first set of symbol values map to a first set of characters including at least one shift character;

parsing the data string to remove any symbol values corresponding to the shift characters and a defined number of subsequent symbol values from the data string, the shift character and defined number of subsequent symbol values comprising a set of parsed symbol values;

converting each set of parsed symbol values into a character code, the character code selected from a first set of character codes;

converting each of the symbol values in the parsed data string into a character code, the character code selected from the first set of character codes; and

assembling the character codes into a data string.

38. The method of claim 37, further comprising the steps of:

imaging a symbol, the symbol comprising a plurality of symbol characters;

converting the imaged symbol into a data string comprising the plurality of symbol values, each of the symbol values corresponding to a respective one of the symbol characters; and

outputting the symbol values as the data string.

39. The method of claim 37, wherein the step of converting the single byte symbols into double byte character codes comprises the steps of:

converting each of the single byte symbol values into a single byte character code; and

converting each of the single byte character codes into the double byte character code.

40. The method of claim 37, further comprising the steps of:

imaging a symbol to produce a signal representative of each of a plurality of symbol characters comprising the symbol;

analyzing the signal to identify the symbol characters; and

converting each of the symbol characters into a corresponding symbol value.

41. An article of manufacture having computer readable program embodied therein for causing a data string to be converted into an optical code, the computer readable program in said article of manufacture comprising the steps of:

receiving the data string comprising a plurality of double byte character codes corresponding to data characters from a double byte character set, a number of the data characters from the double byte character set also belonging to a single byte character set, the optical symbol comprising a number of single byte symbol elements and double byte symbol elements;

parsing the data string to separate the double byte character codes of data characters in the single byte character set from the data string

converting each of the double byte character codes in the parsed data string into a combination of symbol values;

converting each of the double byte character codes parsed from the data string into a respective symbol value; and

outputting the symbol values to a printer for printing the optical symbol.

42. An article of manufacture having computer readable program embodied therein for causing a string of symbol values to be converted into a string of character codes, the computer readable program in said article of manufacture comprising the steps of:

receiving the string of symbol values selected from a set of symbol values, wherein the set of symbol values map to a set of characters comprising a set of double byte characters and a subset of single byte characters;

parsing the string to separate the symbol values corresponding to the single byte data characters from the symbol values corresponding to the double byte data characters;

converting each pair of the symbol values corresponding to a double byte data character into one character code from a first set of character codes, and converting each of the symbol values corresponding to a single byte data character into one character code from the first set of character codes; and

assembling the character codes into the string of character codes.

43. A method converting a plurality of two byte character codes into a set of symbol characters, the method comprising the steps of:

receiving the plurality of two byte character codes, each character code representing a data character chosen from a two byte character set;

identifying as single byte character codes any of the character codes in the plurality of character codes which represents a data character from a one byte character set, the data characters in the one byte character set being a subset of the data characters in the two byte character set;

identifying as double byte character codes all of the character codes not identified as single byte character codes in the plurality of character codes;

converting each of the character codes identified as single byte character codes into a respective symbol character; and

converting each of the character codes identified as two byte character codes into a combination of respective symbol characters.

44. A method converting a plurality of symbol values into a set of character codes, the method comprising the steps of:

receiving the plurality of symbol values, each symbol value representing a symbol character;

identifying as double byte symbol values each combination of symbol values in the plurality of symbol values which represents a single data character;

identifying as single byte symbol values any of the symbol values in the plurality of symbol values not identified as double byte symbol values;

converting each of the symbol values identified as single byte symbol values into a respective double byte character code; and

converting each combination of symbol values identified as two byte character codes into a respective double byte character code.

45. The method of claim 44 wherein the step of converting each of the symbol values identified as single byte symbol values into a respective double byte character code includes the steps of:

searching a table of double byte character codes to find the respective double byte character code.

46. The method of claim 44 wherein the step of converting each of the symbol values identified as single byte symbol values into a respective double byte character code includes the steps of:

searching a table of single byte character codes to find a respective single byte character code; and

appending a fixed single byte value to the respective single byte character code to define the respective double byte character code.

47. The method of claim 44 wherein the step of converting each of the symbol values identified as single byte symbol values into a respective double byte character code includes the steps of:

calculating the respective double byte character code from a defined algorithm having the symbol value as a parameter.