Processing techniques for visual capture data from a rendered document

1. A method in a computing system for navigating an electronic document, comprising:

electronically capturing a portion of a rendered document, the portion including a text fragment within the rendered document;

in response to the capture, identifying (1) an electronic document contained in a corpus of electronic documents, the identified electronic document containing the captured document portion, and (2) a position within the identified electronic document at which the selected document portion occurs;

accessing a markup layer that relates to the identified electronic document and determines custom actions to be made available in response to captures from particular positions in the identified electronic document;

identifying actions associated with the identified position in the identified electronic document, wherein at least one of the identified actions was associated with the identified position in the identified electronic document before an occurrence of an electronic capture of the portion of the rendered document; and

making the identified actions available to a user who captured the portion of the rendered document.

2. The method of claim 1 wherein the identified electronic document and the identified position are identified without determining a standard-character-set representation of the selected document portion.

3. The method of claim 2 wherein the identification is performed using a convolution-encoded representation of text contained by the selected document portion.

4. The method of claim 3 , further comprising:

encoding two selected document portions each into a convolution-encoded representation, the two selected document portions containing text of two different natural languages.

5. The method of claim 3 , further comprising:

encoding data that is independent of textual content of the selected document portion in the convolution-encoded representation, wherein encoding data comprises including an invalid value in the convolution-encoded representation.

6. The method of claim 2 wherein the selected document portion is unique among the corpus of electronic documents, and a version of the selected document portion from which a single word is deleted is not unique among the corpus of electronic documents.

7. The method of claim 1 , wherein electronically capturing a portion of a rendered document includes optically capturing an image of the portion of the rendered document.

8. The method of claim 1 , wherein electronically capturing a portion of a rendered document includes capturing a user speaking the text fragment within the portion of the rendered document.

9. A computer-readable storage medium whose contents cause a mobile phone to perform a method for navigating an electronic document, the method comprising:

electronically capturing a portion of a rendered document, the portion constituting a text fragment within the rendered document, wherein electronically capturing the portion of the rendered document includes optically capturing an image of the portion using a camera of a mobile phone or capturing a spoken version of the text fragment within the rendered document using a microphone of the mobile phone;

in response to the capture of the portion of the rendered document, identifying (1) an electronic document contained in a corpus of electronic documents, the identified electronic document containing the captured document portion, and (2) a position within the identified electronic document at which the selected document portion occurs;

accessing a markup layer for the identified electronic document that associates actions to be performed to particular positions in the identified electronic document;

identifying actions using the accessed markup layer associated with the identified position in the identified electronic document, wherein at least one of the identified actions was associated with the identified position in the identified electronic document before an occurrence of an electronic capture of the portion of the rendered document; and

presenting, via a display associated with the mobile phone, one or more user-selecable options to perform the identified actions associated with the identified position in the identified electronic document.

10. The computer-readable medium of claim 9 , wherein accessing the markup layer includes accessing a data structure that maps the actions to be performed with text within the identified positions in the identified rendered document.

11. The computer-readable medium of claim 9 , wherein the identified actions include global actions associated with every particular portion of the rendered document.

12. A system for navigating an electronic document, the system comprising:

means for optically capturing a text based portion of a rendered document;

means for recognizing the text within the optically captured text based portion of the rendered document;

means for identifying (1) an electronic document contained in a corpus of electronic documents, the identified electronic document containing the text based portion, and (2) a position within the identified electronic document at which the optical capture occurs;

means for accessing a markup layer that relates to the identified electronic document and determines custom actions to be made available in response to captures from particular positions in the identified electronic document

means for identifying two or more actions associated with the identified position in the identified electronic document, wherein the identified two or more actions includes an action associated with the identified position in the identified electronic document before an occurrence of an optical capture of the text based portion of the rendered document; and

means for displaying user-selectable options associated with the identified two or more actions.

13. The system of claim 12 , wherein the identified two or more actions includes an action dynamically generated after an occurrence of an optical capture of the text based portion of the rendered document.