LoadZonesAsync Method (IOcrDocument)

IAsyncAction LoadZonesAsync( 
   IStorageFile file
)

'Declaration
 
Function LoadZonesAsync( _
   ByVal file As IStorageFile _
) As IAsyncAction

'Usage
 
Dim instance As IOcrDocument
Dim file As IStorageFile
Dim value As IAsyncAction
 
value = instance.LoadZonesAsync(file)

IAsyncAction LoadZonesAsync( 
   IStorageFile file
)

function Leadtools.Forms.Ocr.IOcrDocument.LoadZonesAsync( 
   file 
)

IAsyncAction^ LoadZonesAsync( 
   IStorageFile^ file
) 

Parameters

file

The Windows Runtime storage containing the zones to load.

To save and load the zones of OCR pages, you can use one of these methods:

• IOcrPage.SaveZonesAsync(storageFile): This method save the zones of a particular OCR page to a single-page storage file. This method will not use the page number, and hence, the file will contain zones that are not tied to any particular page and can be loaded back into any OCR page regardless of its number. To load these zones back into any OCR page, use IOcrPage.LoadZonesAsync(storageFile).

• IOcrPage.SaveZonesAsync(storageFile, pageNumber): This method save the zones of a particular OCR page to a multi-page file. If the file exists previously, these methods will replace the zones specified in 'pageNumber' with the zones of the IOcrPage. If the file does not contain zones for the specified page number, the zones will be appended to the file or stream at the end and can be loaded later using IOcrPage.LoadZonesAsync(file, pageNumber).

• IOcrDocument.SaveZonesAsync(file): This method save the zones of all the OCR pages in a document to a multi-page file. The saved data will contain the page number of the zones. To load these zones, you can use IOcrDocument.LoadZonesAsync(file) to load the zones from a multi-page file back into a multi-page OCR document. Or IOcrPage.LoadZonesAsync(file, pageNumber) to load any single page from a multi-page OCR document into a particular OCR page.

Note on loading zones from a multi-page zone file: If the file does not contain zones data with the correct page number, the engine will not load any zones for this page. After the method returns, any OCR page that did not have zones data will contain zero zones. (the IOcrPage.Zones property conatins 0 items). You can then use IOcrPage.AutoZone if required to re-zone this page.

Use this method to load the zones previously saved into a multi-page zones disk file with the IOcrDocument.SaveZones(fileName) method.

The zones of this page will first be cleared prior to loading the new items.

After this method finishes, you can access the loaded zones in the IOcrPage.Zones property.

Saving zones to an external file or a stream could be useful when you are processing forms. For example, you can load one of the forms and automatically find the zones inside it using AutoZone, if the automatic zone detection was not 100 percent satisfactory, you can update the zones in the IOcrPage.Zones collection manually and then save the result with IOcrDocument.SaveZonesAsync(file). Once the zones are saved. You can now process all similar forms in the following manner:

• Add the form page or pages to an OCR document using the Pages collection of IOcrDocument.
• Load the zones previously saved for each page using IOcrDocument.LoadZonesAsync(file).
• Skip calling AutoZone and directly call IOcrPage.Recognize or IOcrPage.RecognizeText. This will also speed up the recognition process considerably.

Target Platforms

Reference

IOcrDocument Interface
IOcrDocument Members
IOcrPage.LoadZonesAsync(file)
IOcrPage.LoadZonesAsync(file, pageNumber)
IOcrPage.SaveZonesAsync(file)
IOcrPage.SaveZonesAsync(file, pageNumber)
IOcrDocument.SaveZonesAsync(file)
IOcrPageCollection Interface
IOcrZoneCollection Interface
OcrZone Structure
IOcrPage.Recognize
Programming with the LEADTOOLS .NET OCR