Processing techniques for visual capture data from a rendered document

Abstract

A facility for navigating an electronic document is described. The facility receives user input selecting a portion of the content of a rendered document that constitutes a sentence fragment. In response to receiving the user input, the facility identifies an electronic document contained in a corpus of electronic documents, the identified electronic document containing the selected document portion. In response to receiving the user input, the facility further identifies a position within the identified electronic document at which the selected document portion occurs.

1 . (canceled) 
     
     
         2 . A method performed by a data processing apparatus, the method comprising:
 receiving data specifying a text input;   for a particular alphanumeric character that occurs in the text input, determining a quantity of other characters between an initial occurrence of the particular alphanumeric character in the text input and a successive occurrence of the particular alphanumeric character in the text input;   identifying, from a corpus of electronic documents, an electronic document that includes a text portion having successive occurrences of the particular alphanumeric character separated by the same quantity of other characters; and   providing, for presentation on a display device, at least a portion of the identified electronic document.   
     
     
         3 . The method of  claim 2 , further comprising:
 for each of a plurality of additional alphanumeric characters that occur in the text input, determining a quantity of other characters between an initial occurrence of the additional alphanumeric character in the text input and a successive occurrence of the additional alphanumeric character in the text input; and   generating a sequence of numbers for the text input using the quantity of other characters for the particular alphanumeric character and the quantity of other characters for each additional alphanumeric character, the sequence of numbers being in a same order as the particular alphanumeric character and the additional alphanumeric characters occur in the text input.   
     
     
         4 . The method of  claim 3 , further comprising:
 identifying a particular number in the sequence of numbers and a successive number that follows the particular number in the sequence of numbers;   determining a difference between the particular number and the successive number; and   identifying an action to perform based on the difference.   
     
     
         5 . The method of  claim 4 , wherein the action comprises identifying additional data encoded in the sequence of numbers. 
     
     
         6 . The method of  claim 4 , wherein:
 the successive number immediately follows the particular number in the sequence of numbers; and   the action comprises generating an error alert in response to determining that the difference between the particular number and the successive number has a particular value.   
     
     
         7 . The method of  claim 3 , wherein identifying the electronic document comprises:
 identifying, for each electronic document in the corpus of electronic documents, a sequence of numbers based on quantities of characters that occur in the electronic document between successive occurrences of particular characters in the electronic document; and   determining that the sequence of numbers for the identified electronic document includes the sequence of numbers for the text input.   
     
     
         8 . The method of  claim 3 , further comprising:
 identifying multiple occurrences of a subsequence of numbers in the sequence of numbers; and   compressing the sequence of numbers based on the multiple occurrences.   
     
     
         9 . A system comprising:
 a data processing apparatus; and   a memory apparatus in data communication with the data processing apparatus and storing instructions executable by the data processing apparatus and that upon such execution cause the data processing apparatus to perform operations comprising:
 receiving data specifying a text input; 
 for a particular alphanumeric character that occurs in the text input, determining a quantity of other characters between an initial occurrence of the particular alphanumeric character in the text input and a successive occurrence of the particular alphanumeric character in the text input; 
 identifying, from a corpus of electronic documents, an electronic document that includes a text portion having successive occurrences of the particular alphanumeric character separated by the same quantity of other characters; and 
 providing, for presentation on a display device, at least a portion of the identified electronic document. 
   
     
     
         10 . The system of  claim 9 , wherein the operations further comprise:
 for each of a plurality of additional alphanumeric characters that occur in the text input, determining a quantity of other characters between an initial occurrence of the additional alphanumeric character in the text input and a successive occurrence of the additional alphanumeric character in the text input; and   generating a sequence of numbers for the text input using the quantity of other characters for the particular alphanumeric character and the quantity of other characters for each additional alphanumeric character, the sequence of numbers being in a same order as the particular alphanumeric character and the additional alphanumeric characters occur in the text input.   
     
     
         11 . The system of  claim 10 , wherein the operations further comprise:
 identifying a particular number in the sequence of numbers and a successive number that follows the particular number in the sequence of numbers;   determining a difference between the particular number and the successive number; and   identifying an action to perform based on the difference.   
     
     
         12 . The system of  claim 11 , wherein the action comprises identifying additional data encoded in the sequence of numbers. 
     
     
         13 . The system of  claim 11 , wherein:
 the successive number immediately follows the particular number in the sequence of numbers; and   the action comprises generating an error alert in response to determining that the difference between the particular number and the successive number has a particular value.   
     
     
         14 . The system of  claim 10 , wherein identifying the electronic document comprises:
 identifying, for each electronic document in the corpus of electronic documents, a sequence of numbers based on quantities of characters that occur in the electronic document between successive occurrences of particular characters in the electronic document; and   determining that the sequence of numbers for the identified electronic document includes the sequence of numbers for the text input.   
     
     
         15 . The system of  claim 10 , wherein the operations further comprise:
 identifying multiple occurrences of a subsequence of numbers in the sequence of numbers; and   compressing the sequence of numbers based on the multiple occurrences.   
     
     
         16 . A computer storage medium encoded with a computer program, the program comprising instructions that when executed by data processing apparatus cause the data processing apparatus to perform operations comprising:
 receiving data specifying a text input;   for a particular alphanumeric character that occurs in the text input, determining a quantity of other characters between an initial occurrence of the particular alphanumeric character in the text input and a successive occurrence of the particular alphanumeric character in the text input;   identifying, from a corpus of electronic documents, an electronic document that includes a text portion having successive occurrences of the particular alphanumeric character separated by the same quantity of other characters; and   providing, for presentation on a display device, at least a portion of the identified electronic document.   
     
     
         17 . The computer storage medium of  claim 16 , wherein the operations further comprise:
 for each of a plurality of additional alphanumeric characters that occur in the text input, determining a quantity of other characters between an initial occurrence of the additional alphanumeric character in the text input and a successive occurrence of the additional alphanumeric character in the text input; and   generating a sequence of numbers for the text input using the quantity of other characters for the particular alphanumeric character and the quantity of other characters for each additional alphanumeric character, the sequence of numbers being in a same order as the particular alphanumeric character and the additional alphanumeric characters occur in the text input.   
     
     
         18 . The computer storage medium of  claim 17 , wherein the operations further comprise:
 identifying a particular number in the sequence of numbers and a successive number that follows the particular number in the sequence of numbers;   determining a difference between the particular number and the successive number; and   identifying an action to perform based on the difference.   
     
     
         19 . The computer storage medium of  claim 18 , wherein the action comprises identifying additional data encoded in the sequence of numbers. 
     
     
         20 . The computer storage medium of  claim 18 , wherein:
 the successive number immediately follows the particular number in the sequence of numbers; and   the action comprises generating an error alert in response to determining that the difference between the particular number and the successive number has a particular value.   
     
     
         21 . The computer storage medium of  claim 17 , wherein identifying the electronic document comprises:
 identifying, for each electronic document in the corpus of electronic documents, a sequence of numbers based on quantities of characters that occur in the electronic document between successive occurrences of particular characters in the electronic document; and   determining that the sequence of numbers for the identified electronic document includes the sequence of numbers for the text input.