Mixed media reality brokerage network with layout-independent recognition

1. A computer-implemented method for layout independent recognition of an input document, the method comprising:

receiving an electronic document as the input document;

rendering the electronic document using a layout process to produce a layout independent document with a layout defined by the layout process;

extracting an image patch from the layout independent document;

segmenting the image patch into an input text strip; and

locating from a plurality of stored pages a page with a matching text strip that matches the input text strip to produce a candidate page corresponding to the electronic document.

2. The method of claim 1 , further comprising performing a layout independent mixed media reality action.

3. The method of claim 2 , further wherein the layout independent mixed media reality action is one from the group of: performing patch detection, performing patch modification, regenerating a database document, and re-rendering a document using an electronic document from a database.

4. The method of claim 1 , further comprising:

locating pages each having a matching text strip that matches the input text strip to produce candidate pages; and

ranking the candidate pages according to an amount of similarity to the text strips.

5. The method of claim 4 , wherein locating pages uses a strip fragment candidate generation process to produce a set of strip candidates, each defined by a document ID, a page ID, and bounding boxes of strips as they occur in database documents.

6. The method of claim 4 , wherein locating pages comprises:

performing feature extraction;

performing a database look up for matching features; and

adding matching documents to the candidate set.

7. The method of claim 4 , wherein locating pages includes determining document-pages in a database that could have generated the input image using a vertical context to limit the page candidates.

8. The method of claim 4 , wherein locating pages comprises:

determining matching document pages from a database;

modifying a feature extraction score of each matching page;

sorting the matching document pages from highest score to lowest score;

calculating a percentage of the image patch found in the matching page; and

outputting the matching document pages sorted by percentage.

9. The method of claim 8 , wherein modifying is based at least in part on a term frequency-inverse document frequency measure.

10. The method of claim 8 , further comprising estimating a length of each line of text by comparing a linear position of a beginning of each character string in the database document and calculating a gap between strips of text with a difference between a first character and a last character in the previous strip.

11. The method of claim 8 , further comprising estimating the column width from which the image patch was extracted.

12. The method of claim 4 , further comprising grading candidate pages to determine the pre-specified patches that match the image patch.

13. The method of claim 12 , wherein grading candidate pages includes assigning a score proportional to the amount of a patch covered by the text in the image patch.

14. The method of claim 1 , wherein performing further comprising estimating characteristics of text within the extracted image patch.

15. The method of claim 1 , wherein segmenting the image patch produces an ordered set of text strips, one per line of text.

16. A computer-readable storage medium containing computer program instructions for layout independent recognition of an input document, the computer program instructions performing the steps of:

receiving an electronic document as the input document;

rendering the electronic document using a layout process to produce a layout independent document with a layout defined by the layout process;

extracting an image patch from the layout independent document;

segmenting the image patch into an input text strip; and

locating from a plurality of stored pages a page with a matching text strip that matches the input text strip to produce a candidate page corresponding to the electronic document.

17. The computer-readable storage medium of claim 16 , further comprising:

locating pages each having a matching text strip that matches the input text strip to produce candidate pages; and

ranking the candidate pages according to an amount of similarity to the text strips.

18. The computer-readable storage medium of claim 17 , wherein locating pages comprises:

performing feature extraction;

performing a database look up for matching features; and

adding matching documents to the candidate set.

19. A system for layout independent recognition of an input document, the system comprising:

a processor;

means for receiving an electronic document as the input document;

means for rendering the electronic document using a layout process to produce a layout independent document with a layout defined by the layout process;

means for extracting an image patch from the layout independent document;

means for segmenting the image patch into an input text strip; and

means for locating from a plurality of stored pages a page with a matching text strip that matches the input text strip to produce a candidate page corresponding to the electronic document.

20. The system of claim 19 , further comprising:

means for locating pages each having a matching text strip that matches the input text strip to produce candidate pages; and

means for ranking the candidate pages according to an amount of similarity to the text strips.