Leadtools.Forms.Ocr Namespace > IOcrPageCollection Interface > AddDib Method : AddDib(IBuffer,OcrProgressCallback) Method |
IOcrPage AddDib( IBuffer dib, OcrProgressCallback callback )
'Declaration Overloads Function AddDib( _ ByVal dib As IBuffer, _ ByVal callback As OcrProgressCallback _ ) As IOcrPage
'Usage Dim instance As IOcrPageCollection Dim dib As IBuffer Dim callback As OcrProgressCallback Dim value As IOcrPage value = instance.AddDib(dib, callback)
IOcrPage AddDib( IBuffer dib, OcrProgressCallback callback )
function Leadtools.Forms.Ocr.IOcrPageCollection.AddDib(IBuffer,OcrProgressCallback)( dib , callback )
IOcrPage^ AddDib( IBuffer^ dib, OcrProgressCallback^ callback )
This method will add a device independent bitmap (DIB) stored in Windows Runtime IBuffer to the OCR document.
This method will add the page to the end of the collection if you already have pages in this IOcrPageCollection.
You can use the OcrProgressCallback to show the operation progress or to abort it. For more information and an example, refer to OcrProgressCallback.
The LEADTOOLS OCR engine supports pages of dots per inch (DPI) values of 150 and greater. If you try to add a page with a DPI of less than 150 then the engine might be able to recognize any data from this page.
Note, the LEADTOOLS Plus OCR engine does not support image size greater than A3 paper size (11.7 by 16.5 inches at 300 dpi). Attempting to add an image that has a size greater than A3 will result in an error. For document of size greater than the maximum allowed, you must first resize the image before adding it to the LEADTOOLS Plus OCR engine. The Professional and Advantage engines do not have a restriction on the image size.
Note: The value of the "Recognition.ShareOriginalImage" (only supported by the Advantage OCR engine) setting is not used when calling this method. The engine loads the image(s) and sets them in the pages internally. The original image reference can be obtained from the page using IOcrPage.GetRasterImage(OcrPageType.Original). Sharing the original image minimizes the memory used during OCR operations.
Imports Leadtools Imports Leadtools.Codecs Imports Leadtools.Forms.Ocr Imports Leadtools.Forms Imports Leadtools.Forms.DocumentWriters Imports Leadtools.WinForms Imports Leadtools.ImageProcessing.Core Imports Leadtools.Drawing Public Sub AddPageFromDibExample() Dim tifFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.tif") Dim bmpFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.bmp") Dim pdfFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.pdf") ' Get a DIB ' In this example, we will save the TIF file as BMP, then load it without the BITMAPFILEHEADER structure ' The result is a valid Windows DIB Using codecs As New RasterCodecs() codecs.Convert(tifFileName, bmpFileName, RasterImageFormat.Bmp, 0, 0, 1, Nothing) End Using ' From MSDN Dim bitmapFileHeaderStructSize As Integer = 14 Dim dib As IntPtr = IntPtr.Zero Using fs As FileStream = File.OpenRead(bmpFileName) ' Allocate the DIB Dim dibSize As Integer = CType(fs.Length - bitmapFileHeaderStructSize, Integer) dib = Marshal.AllocHGlobal(dibSize) Dim dibOffset As Integer = 0 ' Now read it fs.Seek(bitmapFileHeaderStructSize, SeekOrigin.Begin) Dim bufferSize As Integer = 1024 * 4 Dim buffer(bufferSize - 1) As Byte Dim bytes As Integer = 0 Do bytes = fs.Read(buffer, 0, bufferSize) If (bytes > 0) Then Dim dibPtr As New IntPtr(dib.ToInt64() + dibOffset) Marshal.Copy(buffer, 0, dibPtr, bytes) dibOffset += bytes End If Loop While (bytes > 0) End Using ' Create an instance of the engine Using ocrEngine As IOcrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, False) ' Start the engine using default parameters ocrEngine.Startup(Nothing, Nothing, Nothing, LEAD_VARS.OcrAdvantageRuntimeDir) ' Create an OCR document Using ocrDocument As IOcrDocument = ocrEngine.DocumentManager.CreateDocument() ' Add the image ocrDocument.Pages.AddDib(dib, Nothing) ' Free the DIB since we do not need it anymore Marshal.FreeHGlobal(dib) ' Recognize ocrDocument.Pages.Recognize(Nothing) ' Save ocrDocument.Save(pdfFileName, DocumentFormat.Pdf, Nothing) End Using ' Shutdown the engine ' Note: calling Dispose will also automatically shutdown the engine if it has been started ocrEngine.Shutdown() End Using End Sub Public NotInheritable Class LEAD_VARS Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images" Public Const OcrAdvantageRuntimeDir As String = "C:\LEADTOOLS 18\Bin\Common\OcrAdvantageRuntime" End Class
using Leadtools; using Leadtools.Codecs; using Leadtools.Forms.Ocr; using Leadtools.Forms.DocumentWriters; using Leadtools.Forms; using Leadtools.ImageProcessing.Core; public void AddPageFromDibExample() { string tifFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.tif"); string bmpFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.bmp"); string pdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.pdf"); // Get a DIB // In this example, we will save the TIF file as BMP, then load it without the BITMAPFILEHEADER structure // The result is a valid Windows DIB using (RasterCodecs codecs = new RasterCodecs()) codecs.Convert(tifFileName, bmpFileName, RasterImageFormat.Bmp, 0, 0, 1, null); // From MSDN const int bitmapFileHeaderStructSize = 14; IntPtr dib = IntPtr.Zero; using (FileStream fs = File.OpenRead(bmpFileName)) { // Allocate the DIB int dibSize = (int)fs.Length - bitmapFileHeaderStructSize; dib = Marshal.AllocHGlobal(dibSize); int dibOffset = 0; // Now read it fs.Seek(bitmapFileHeaderStructSize, SeekOrigin.Begin); const int bufferSize = 1024 * 4; byte[] buffer = new byte[bufferSize]; int bytes = 0; do { bytes = fs.Read(buffer, 0, bufferSize); if (bytes > 0) { IntPtr dibPtr = new IntPtr(dib.ToInt64() + dibOffset); Marshal.Copy(buffer, 0, dibPtr, bytes); dibOffset += bytes; } } while (bytes > 0); } // Create an instance of the engine using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, false)) { // Start the engine using default parameters ocrEngine.Startup(null, null, null, LEAD_VARS.OcrAdvantageRuntimeDir); // Create an OCR document using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument()) { // Add the image ocrDocument.Pages.AddDib(dib, null); // Free the DIB since we do not need it anymore Marshal.FreeHGlobal(dib); // Recognize ocrDocument.Pages.Recognize(null); // Save ocrDocument.Save(pdfFileName, DocumentFormat.Pdf, null); } // Shutdown the engine // Note: calling Dispose will also automatically shutdown the engine if it has been started ocrEngine.Shutdown(); } } static class LEAD_VARS { public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images"; public const string OcrAdvantageRuntimeDir = @"C:\LEADTOOLS 18\Bin\Common\OcrAdvantageRuntime"; }
using Leadtools; using Leadtools.Codecs; using Leadtools.Forms.Ocr; using Leadtools.Forms.DocumentWriters; using Leadtools.Forms; using Leadtools.ImageProcessing.Core; [TestMethod] public async Task AddPageFromDibExample() { string tifFileName = @"Assets\Ocr1.tif"; string bmpFileName = "Ocr1.bmp"; string pdfFileName = "Ocr1.pdf"; // Get a DIB // In this example, we will save the TIF file as BMP, then load it without the BITMAPFILEHEADER structure // The result is a valid Windows DIB StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(tifFileName); StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(bmpFileName, CreationCollisionOption.ReplaceExisting); RasterCodecs codecs = new RasterCodecs(); await codecs.ConvertAsync(LeadStreamFactory.Create(loadFile), LeadStreamFactory.Create(saveFile), RasterImageFormat.Bmp, 0, 0, 1, null); Windows.Storage.Streams.IBuffer dib; loadFile = await Tools.AppLocalFolder.GetFileAsync(bmpFileName); using (RasterImage image = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile))) { dib = image.ToDib(RasterConvertToDibType.BitmapInfoHeader); } // Create an instance of the engine IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, false); // Start the engine using default parameters ocrEngine.Startup(null, null, String.Empty, Tools.OcrEnginePath); // Create an OCR document IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument(); // Add the image ocrDocument.Pages.AddDib(dib, null); // Recognize ocrDocument.Pages.Recognize(null); // Save saveFile = await Tools.AppLocalFolder.CreateFileAsync(pdfFileName, CreationCollisionOption.ReplaceExisting); await ocrDocument.SaveAsync(LeadStreamFactory.Create(saveFile), DocumentFormat.Pdf, null); // Shutdown the engine ocrEngine.Shutdown(); }