Word recognition apparatus

• US 4,010,445 A
• Filed: 09/19/1975
• Issued: 03/01/1977
• Est. Priority Date: 09/25/1974
• Status: Expired due to Term

• Current Assignee: Nippon Electric Company Limited (NEC Corporation)
• Original Assignee: Nippon Electric Company Limited (NEC Corporation)
• Inventors: Hoshino, Yukio
• Primary Examiner(s): Thesz, Joseph M.
• Application Number:
  US05/614,984
• Time in Patent Office: 529 Days
• Field of Search: 340/146.3 WD, 340/172.5
• US Class Current: 382/231
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/262 using context analysis, e.g. lexical, syntactic or semantic context

Abstract

A word recognition apparatus using a dictionary of words is disclosed. The apparatus comprises, first of all, word storing means which stores words based on the classification of a plurality of words to be retrieved in block units. The words are stored in the order of block numbers so that characters placed in one or more given positions of a word forming an input character string may be used as a retrieving key. A block-starting-address storing means is provided for storing starting addresses of the clock units in the word storing means. A block-starting-address and limit-address taking-out means takes out a block starting address corresponding to a designated block number and a block limit address corresponding to a block number next to the designated number from the blockstarting-address storing means. An input-character-string storing means stores the string of characters recognized by a character recognition system. A block-number determining means responsive to the input-character-string storing means sequentially designates the number of blocks containing words having recognized characters of characters placed in the retrieving key positions of the input character string. A word taking-out means sequentially takes out words stored in the addresses beginning with the block starting address of the word storing means and ending with an address short of the block limit address by using the starting address and the block limit address which are taken out from the block-starting address storing means with the block number used as the retrieving key. Finally, a word comparing means is provided for detecting a word similar to the input character string to a degree over a given value by the comparison of the words thus taken out with the input character string.

Claims

1. A word recognition apparatus for use with a character recognition system, comprising:

a. word storing means for storing a plurality of words to be retrieved in block units in the order of block numbers so that characters placed in one or more given positions of a word forming an input character string are used as a retrieving key corresponding to one of said block numbers;

b. block-starting-address storing means for storing starting addresses of the block units in said word storing means;

c. block-starting-address and limit-address taking-out means for taking out a block starting address and a block limit address corresponding to a block number next to the designated block number from the block-starting-address storing means;

d. input-character-string storing means for storing the input character string recognized by said character recognition system;

e. block-number determining means for sequentially designating the block numbers of blocks containing words having recognized characters placed in said given positions of said input character string;

f. word taking-out means for sequentially taking out words stored in the addresses from the block starting address of said word storing means to an address short of said block limit address by using the starting address and the block limit address which are taken out from the block-starting-address storing means with a block number used as the retrieving key; and

g. word comparing means for detecting a word similar to the input character string to a degree over a given value by the comparison of the words thus taken out with said input character string.

2. A word recognition apparatus as recited in claim 1 wherein said block-number determining means comprises:

a. character pattern classifying means connected to said input-character-string storing means and responsive to characters placed in said given positions including rejection symbols generated by said character recognition system for generating an initial block number corresponding to the recognized characters in said given positions and for generating a block spacing value corresponding to the rejection symbols;

b. block spacing register means responsive to said character pattern classifying means for storing said block spacing value;

c. adder means connected to receive said initial block number from said character pattern classifying means and said block spacing value from said block spacing register means for sequentially generating said block numbers; and

d. counter means for counting the number of block numbers generated by said adder means and generating a signal indicating that all blocks containing words having recognized characters of characters placed in said given positions have been taken out of said word storing means and compared in said word comparing means with the string of characters stored in said input-character-string means.

3. A word recognition apparatus as recited in claim 2 wherein at least three characters in said given positions of a word forming an input character string are used as the retrieving key corresponding to one of said block numbers and said character pattern classifying means comprises:

a. first, second and third code generating means connected to said input-character storing means for generating weighted codes corresponding respectively to each recognized character in one of said given positions, said weighted codes being added by said adder means to form said initial block number;

b. first, second and third rejection symbol detectors connected to said input-character storing means for generating outputs indicating when no recognized character is in a respective one of said given positions; and

c. block spacing generating means responsive to the outputs of said first, second and third rejection symbol detectors for generating a block spacing value depending on which given position has no recognized character.

4. A word recognition apparatus as recited in claim 3 wherein said character pattern classifying means further comprises means responsive to two or more outputs from said first, second and third rejection symbol detectors for generating a signal indicating that recognition of the string of characters stored in the input-character-string storing means is impossible.