This feature allows a user to specify a ‘Key-Value pair’ which can be used for extracting document level index field values based on relative location of ‘value’ against a specified key.
User is provided with ‘Add’ and ‘Edit’ buttons to define and modify the KV patterns. These buttons are available on KV Extraction Rule node present under each index field:
Figure: Key Value Extraction Grid under Batch Class Management
As soon as user will click on any of the above specified buttons, another UI will open up with following options with text boxes and labels displayed.
Figure: Key Value Extraction View
Each key value field consists of following attributes in KV extraction:
- Key Pattern (regex or other pre-defined field)
- Value Pattern (regex)
- Fuzzy Percent (None, 10%, 20% or 30%)
- Fetch Value (First, Last or All)
- Page Value (First, Last or All)
- Zone Value(All, Top, Left, Right, Middle or Bottom)
- Weight (0 to 1)
Key: Regular expression pattern for the key.
Value: Regular expression pattern for the value.
Fuzzy Percent: Fuzzy percent option returns extracted results that match a pattern approximately.
Allowed user values are none, 10%, 20% and 30%.
Fetch Value: User can specify following fetch value while defining advanced key value pair:
- First to extract only first data from the value zone matching the value pattern specified.
- Last to extract only last data from the value zone matching the value pattern specified.
- All to extract only all data from the value zone matching the value pattern specified.
Page Value: User can specify following page value while defining advanced key value pair:
- ALL KV Extraction will be performed on all pages of the document.
- FIRST KV Extraction will be performed on first page of the document.
- LAST KV Extraction will be performed on last page of the document.
Weight: multiplied with confidence score value to calculate new confidence score.
Anchor to be used for multiple fields:
It aims to use the result of previously extracted document level fields for extraction of other document level fields.
User can use previously defined field as a key while defining key value field for some other document level field.
- There is a “Use Existing Field For Key” checkbox present on KV extraction UI.
- On checking this, a list will be populated with the names of document level fields that can be used as a key.
User can select any of those fields as key.
- Note: Only those document level fields will be shown in drop down whose field order number is less than the field order number of the field for which key value pair is being defined.
- If “Use Existing Field For Key” check box is selected, value of the field selected as key should be captured.
Example: Suppose there are two document level fields State and City, and image contains following data:
While defining the advanced key value field for City,
- Use existing field for key should be checked.
- State should be selected from the drop down for key pattern.
- CALIFORNIA should be captured as key.
- LA should be captured as a value.
Multiple file uploading support is provided on KV extraction screen from 4.0 version. File format supported for uploading are:
Figure: Key Value Extraction File Upload View
Dropdowns and arrow keys are available on menu bar for traversing between files and pages respectively.
Editing Overlays in KV Extraction:
Functionality to edit key and value overlays on the KV Extraction Screen has been made much smoother and easier on the latest 4.0 version.
Default Overlays for key and value appears on the uploaded image. Overlays are resizable and draggable inside the image, which makes working on them much easier.
View OCR Data:
Feature to view OCR’ed contents of image is introduced in version 4.0. ‘View OCR Data’ toggle button is available on menu bar. This button generates the OCR content of the current loaded image and displays it on UI.
Figure: Key Value Extraction View OCR Data View
Feature to view the extracted results from Key-Value pair is enhanced to show the matched values on image. Values extracted from the image based on key and value pattern are drawn on the image and respective details of extraction are shown on bottom panel grid. User can scroll into view by clicking on respective row.
Figure: Key Value Extraction Test KV View
Feature to clear the extracted results from the image and redraws Key-Value overlays.