SaveAsync Method

IAsyncAction SaveAsync( 
   ILeadStream stream,
   DocumentFormat format,
   OcrProgressCallback callback
)

'Declaration
 
Function SaveAsync( _
   ByVal stream As ILeadStream, _
   ByVal format As DocumentFormat, _
   ByVal callback As OcrProgressCallback _
) As IAsyncAction

'Usage
 
Dim instance As IOcrDocument
Dim stream As ILeadStream
Dim format As DocumentFormat
Dim callback As OcrProgressCallback
Dim value As IAsyncAction
 
value = instance.SaveAsync(stream, format, callback)

IAsyncAction SaveAsync( 
   ILeadStream stream,
   DocumentFormat format,
   OcrProgressCallback callback
)

function Leadtools.Forms.Ocr.IOcrDocument.SaveAsync( 
   stream ,
   format ,
   callback 
)

IAsyncAction^ SaveAsync( 
   ILeadStream^ stream,
   DocumentFormat format,
   OcrProgressCallback^ callback
) 

Parameters

stream

The LEADTOOLS stream object to save the final output document to.

format

The document format to use. If this parameter is DocumentFormat.User, then the document saved using the native engine format set in IOcrDocumentManager.EngineFormat if the engine used supports native formats, otherwise an exception will be thrown. Note that saving the OCR results using the native engine formats may produce more accurate results in table and cell positions since the engine has access to extra data that is saved internally.

callback

Optional callback to show operation progress.

Return Value

To get the extension used commonly with the document format specified in format, use DocumentWriter.GetFormatFileExtension.

Each IOcrPage object in the Pages collection of this IOcrDocument object holds its recognition data internally. This data is used by this method to generate the final output document.

Typical OCR operation using the IOcrEngine involves starting up the engine then creating a new IOcrDocument object using the IOcrDocumentManager.CreateDocument method before adding the pages into it and perform either automatic or manual zoning. Once this is done, you can use the IOcrPage.Recognize method of each page to collect the recognition data and store it internally in the page. After the recognition data is collected, you use SaveAsync to save the document to its final format as well as SaveXmlAsync to save as XML.

You can also use the IOcrPage.RecognizeText method to recognize and return the recognition data as a simple System.String object.

You can use SaveAsync as many times as required to save the document to multiple formats. You can also continue to add and recognize pages (through the IOcrPage.Recognize method after you save the document.

For each IOcrPage that is not recognized (the user did not call Recognize and the value of the page IOcrPage.IsRecognized is still false) the IOcrDocument will insert an empty page into the final document.

To get the low level recognition data including the recognized characters and their confidence, use IOcrPage.GetRecognizedCharacters instead.

The IOcrDocument interface implements System.IDisposable, hence you must dispose the IOcrDocument object as soon as you are finished using it. Disposing an IOcrDocument object will free all the pages stored inside its IOcrDocument.Pages collection.

You can use the OcrProgressCallback to show the operation progress or to abort it. For more information and an example, refer to OcrProgressCallback.

Target Platforms

Reference

IOcrDocument Interface
IOcrDocument Members
Leadtools.Forms.DocumentWriters.DocumentFormat
IOcrDocumentManager Interface
IOcrDocument.Save
IOcrDocument.SaveXml
IOcrPage.Recognize
IOcrEngine Interface
OcrEngineManager Class
OcrEngineType Enumeration
Programming with the LEADTOOLS .NET OCR
Files to be Included with Your Application