MULTI-PAGE DOCUMENT RECOGNITION IN DOCUMENT CAPTURE
Techniques to capture document data are disclosed. It is determined that a sequence of pages in a stream of document page images comprise a single multi-page document. Data is extracted from two or more different pages included in the sequence. The data extracted from two or more different pages included in the sequence of pages is used to populate a data entry form associated with the multi-page document.
This application is a continuation of U.S. patent application Ser. No. 16/290,453, filed Mar. 1, 2019, entitled “MULTI-PAGE DOCUMENT RECOGNITION IN DOCUMENT CAPTURE”, which is a continuation of U.S. patent application Ser. No. 15/221,433, filed Jul. 27, 2016, entitled “MULTI-PAGE DOCUMENT RECOGNITION IN DOCUMENT CAPTURE”, issued as U.S. Pat. No. 10,248,858, which is a continuation of U.S. patent application Ser. No. 13/720,671, filed Dec. 19, 2012, entitled “MULTI-PAGE DOCUMENT RECOGNITION IN DOCUMENT CAPTURE” issued as U.S. Pat. No. 9,430,453, which are incorporated herein by reference for all purposes.
BACKGROUND OF THE INVENTIONIn document capture, typically pages are recognized and validated one at a time, in sequence. In the typical approach, each page is processed independently with its own data entry form, value extraction, and validation. In the case of a multi-page document, typically the metadata document generated through document capture for each page has to be mapped to a multi-page structure and data values reconciled across pages through additional processing.
In practice, during data validation human operators typically must navigate through multiple pages and associated data entry forms, for example to compare and reconcile values that occur in different pages, etc. This approach depends on the knowledge of human operators of the location of data in different pages of a multiple page document, and in the worst case may require an operator to hunt through multiple independent pages and/or associated page-specific data entry forms to cross-validate data, for example. In addition, treating each page as a separate document results in suboptimal processing of structures such as tables, which may span multiple pages.
Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings.
The invention can be implemented in numerous ways, including as a process; an apparatus; a system; a composition of matter; a computer program product embodied on a computer readable storage medium; and/or a processor, such as a processor configured to execute instructions stored on and/or provided by a memory coupled to the processor. In this specification, these implementations, or any other form that the invention may take, may be referred to as techniques. In general, the order of the steps of disclosed processes may be altered within the scope of the invention. Unless stated otherwise, a component such as a processor or a memory described as being configured to perform a task may be implemented as a general component that is temporarily configured to perform the task at a given time or a specific component that is manufactured to perform the task. As used herein, the term ‘processor’ refers to one or more devices, circuits, and/or processing cores configured to process data, such as computer program instructions.
A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention. The invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention. These details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured.
Processing a multi-page document as a single entity, with a single corresponding data entry form, in an automated document capture context is disclosed. In various embodiments, the pages comprising a multi-page document are identified and associated with a multi-page document type. A corresponding data entry form is used to provide a structured representation of data extracted from the pages of the multi-page document. Structures that may span multiple pages, such as a table or list of values, are associated together in a single array or other structure of the data entry form. Validation of extracted values based on dependency fields that may occur on different pages is facilitated, both in automated processing and in human validation.
In some embodiments, as an operator finishes validation of a field, indicated for example by pressing the “enter” key or selecting another key or on screen control, the system automatically pans to the next data entry form field, retrieves and displays near the form field a corresponding document image snippet. In this way, the operator can navigate through the form and corresponding portions of the document image without retargeting, i.e., without having to redirect their eyes to a different point or points on the screen.
Typically, as noted above pages comprising a multiple page document have been processed separately, each page having its own corresponding electronic data entry form associated with it. The per-page form approach has a number of shortcomings. For example, a value (e.g., an account number on the footer of each page in an invoice) may occur in several pages. An error on a single page results in work for the operator, because typically there is no framework to reconcile data across pages and to auto-correct data. In addition, in production, the operator will only become aware of the problem when he navigates to the page. If there are large discrepancies between values of many pages, then the operator must manually look at each page and that takes time.
In semi-structured and unstructured documents, there can be any number of variations of pages. If the data-entry form is page-based, and a unique form per page is used, this results in an unmanageable number of forms. If a generic form that contains a union of possible fields is used, this results in forms with unused fields. This requires extra work to handle. Furthermore, if a value is copied from another page, its source value and location typically is not shown because only the current page, and not the page from which the copied value was extracted, is shown. If the page is changed, it would result in the data-entry form being changed. Changing the data-entry form then disrupts the sequence of work, resulting in lower operator efficiency.
Under the form-per-page approach, when a table spans multiple pages, the technique of copying data between pages results in a large set of duplicate values. Extra effort is then needed to synchronize if the user makes any changes on any page. The navigation problem described above is compounded. For example, suppose the sub-totals on a multi-page invoice line items table do not add up. It is more cumbersome for the operator to go through each page and then each table, and to work with duplicate row values.
In content management systems, the metadata object is usually not defined per page. To export per-page forms, effort must be made to map values to their corresponding attributes of a metadata object used to represent the multi-page document in the content management system.
In light of all the foregoing shortcomings of the per-page approach to document capture as applied to multi-page documents, automatic detection and processing of a multi-page document as a single document is disclosed. In various embodiments, automatic detection of the pages comprising a multiple page document is performed. Data values are extracted from the pages comprising the document and used to populate a single electronic data entry form for the multi-page document. The operator can then go through the electronic data entry form, for example to validate data fields as required, and the document capture and/or validation system shows the location in the captured document of the corresponding data, regardless of which page(s) it occurs in, rather than the operator having to find and/or choose each page, indexing each independently, and then reconcile later data that occurs in and/or spans multiple pages.
In various embodiments, human operator validation of errors involving fields that have dependency relationships with other fields, such as a “name” value that occurs in more than one page of a multi-page document, is facilitated by displaying the fields together, in a single screen, along with each fields corresponding document image snippet, even if the snippets come from different pages. Likewise, as an operator iterates through error fields in a table or other two dimensional data structure, corresponding snippets are displayed, even if they come from multiple, different pages. The human operator need only navigate through fields in a single data entry form, and the system transparently retrieves and displays for each field its corresponding snippet or other partial image, without regard to page boundaries.
Using techniques described herein, multi-page documents can be processed more efficiently in the document capture context. Values in the same document can be reconciled and either auto-corrected or flagged for manual confirmation without switching between documents or data entry forms, copying over data values from one form to the other, etc. This facilitates use of data redundancy found in many document images. In addition, the data entry form is abstracted from its page definition. The operator does not have to worry about where a value is, enable the operator to focus on validating data on the form. If there are variations in page versions, the operator does not have to worry about it. The location logic will find the right place. In addition, the developer and operator do not have to incur the cost and complexity of copying data back and forth between page forms. Array data is shown in one table, rather than in a table per page, thereby improving the user experience. Finally, it is easier to map content management metadata objects to new document types, since all of the extracted data values for and structure of a multi-page document are capture in one form.
Although the foregoing embodiments have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed embodiments are illustrative and not restrictive.
Claims
1. A method of capturing document data, comprising:
- obtaining a multi-page document;
- extracting data from multiple pages of the multi-page document;
- identifying two or more values located on at least two different pages of the multi-page document, wherein at least a first one of the two or more values is dependent on at least a second one of the two or more values; and
- validating the at least the first one of the two or more values and the at least the second one of the two or more values according to one or more validation rules.
2. The method of claim 1, wherein the validating comprises: accessing a set of validation rules in a library of validation rules; sequentially applying the set of validation rules to the at least the first one of the two or more values and the at least the second one of the two or more values; and marking the at least the first one of the two or more values and the at least the second one of the two or more values as having an error if one of the validation rules fails.
3. The method of claim 2, further comprising receiving a document type definition corresponding to the multi-page document, wherein the document type definition identifies the set of validation rules to be applied to the at least the first one of the two or more values and the at least the second one of the two or more values.
4. The method of claim 3, wherein the document type definition includes a mapping to document type fields to be used to apply each rule.
5. The method of claim 4, further comprising identifying a document type of the multi-page document, and identifying the document type definition based on the identified document type of the multi-page document.
6. The method of claim 5, wherein the document type contains one or more scalar fields and one or more tables of array fields.
7. The method of claim 6, further comprising extracting values from each page into per-page scalar and array fields by name.
8. The method of claim 7, wherein for each extracted value, a corresponding location on the page from which the value was extracted is saved.
9. The method of claim 6, further comprising combining data extracted from the respective pages into a form associated with the document type, wherein combining data extracted from the respective pages into a form associated with the document type includes forming an array that spans multiple pages concatenating a first set of rows of values extracted from a first page with a second set of rows of values extracted from a second page to create a combined set of rows to be included in the document type.
10. The method of claim 1, wherein the validating comprises providing one or more of the at least the first one of the two or more values and the at least the second one of the two or more values to a user for manual validation.
11. The method of claim 10, further comprising presenting an interface to the user, wherein the interface displays to the user a plurality of fields which are marked as having errors and enables the user to iterate through the plurality of fields, wherein the plurality of fields displayed to the user include only dependent fields that require validation.
12. The method of claim 11, further comprising identifying a document type of the multi-page document, and creating an instance of a selected one of a plurality of type-specific data entry forms in a forms library based at least in part on the identified document type of the multi-page document, wherein the plurality of fields displayed to the user are fields contained in the created instance.
13. The method of claim 12, wherein the two or more values presented to the user for manual validation are identified by determining whether the first one of the two or more values matches the second one of the two or more values in the multi-page document.
14. The method of claim 11, wherein the interface is configured to repetitively iterate through each of the plurality of fields until either the user enters data that clears the validation error associated with the field.
15. The method of claim 11, further comprising populating, based at least in part on the data extracted from the multi-page document, a plurality of fields of the instance of the selected data entry form including the plurality of fields displayed to the user.
16. The method of claim 11, wherein as each form field is displayed, a corresponding snippet or other partial image from a page from which a current data value associated with the form field was extracted is displayed adjacent to the field.
17. The method of claim 1, wherein the first and second ones of the two or more values are contained in a table or array of the multi-page document.
18. The method of claim 1, The method further comprising determining that a sequence of pages comprise the multi-page document, wherein determining that a sequence of pages in a stream of document page images comprise the single multi-page document includes processing each page individually to determine a corresponding page type; and processing the stream of page types to identify a sequence associated with a multi-page document type.
19. A document capture system, comprising:
- a communication or other interface configured to receive a multi-page document; and one or more processors coupled to the interface and configured to: obtain a multi-page document; extract data from multiple pages of the multi-page document; identify two or more values located on at least two different pages of the multi-page document, wherein at least a first one of the two or more values is dependent on at least a second one of the two or more values; and validate the at least the first one of the two or more values and the at least the second one of the two or more values according to one or more validation rules.
20. A computer program product to capture document data, the computer program product being embodied in a non-transitory computer readable storage medium and comprising computer instructions for:
- obtaining a multi-page document;
- extracting data from multiple pages of the multi-page document;
- identifying two or more values located on at least two different pages of the multi-page document, wherein at least a first one of the two or more values is dependent on at least a second one of the two or more values; and
- validating the at least the first one of the two or more values and the at least the second one of the two or more values according to one or more validation rules.
Type: Application
Filed: Nov 20, 2020
Publication Date: Mar 11, 2021
Inventor: Ming Fung Ho (Fremont, CA)
Application Number: 16/953,561