public void ExportPages(
int firstPageIndex,
int lastPageIndex,
Stream stream,
RasterImageFormat format,
int bitsPerPixel,
int firstSavePageNumber,
CodecsSavePageMode pageMode
)
firstPageIndex
The zero-based index of the first page to export.
lastPageIndex
The zero-based index of the last page to export. A value of -1 means export up to and including the last page in the OCR document.
stream
The .NET stream to save the pages to.
format
The image file format to use.
bitsPerPixel
The bits/pixel value of the result image file.
firstSavePageNumber
1-based index of the first output page. If the output file already exists, then this parameter lets you control which pages to overwrite and/or where to append the new pages.
pageMode
Determines how to handle the page when saving to multipage formats. This can be one of the following:
Value | Meaning |
---|---|
CodecsSavePageMode.Append | Append the new page(s) to the end of the file. If the file does not exist, this option will create the file and add the pages to it. firstSavePageNumber is not used. |
CodecsSavePageMode.Insert | Insert the new page(s) at the index specified by firstSavePageNumber. |
CodecsSavePageMode.Replace | Replace the page(s) starting at the index specified by firstSavePageNumber. |
CodecsSavePageMode.Overwrite | Overwrite the page(s) starting at the index specified by firstSavePageNumber. |
CodecsSavePageMode.Append | Append the new page(s) to the end of the file. If the file does not exist, this option will create the file and add the pages to it. |
To export one page to a .NET stream, use ExportPages(int pageIndex, Stream stream, RasterImageFormat format, int bitsPerPixel)
. You can export the page to any of the file formats supported by LEADTOOLS. For more information, refer to Summary of All Supported Image File Formats.
This member only works with memory-based documents and will throw an exception otherwise. For more information, refer to IOcrDocumentManager.CreateDocument and Programming with the LEADTOOLS .NET OCR.
This example will add pages to an OCR document before exporting a range of it back to a .NET stream.
using Leadtools;
using Leadtools.Codecs;
using Leadtools.Ocr;
using Leadtools.Document.Writer;
using Leadtools.Forms.Common;
using Leadtools.ImageProcessing.Core;
public void ExportPagesToStream()
{
string tifFileName = Path.Combine(LEAD_VARS.ImagesDir, "OcrMultiPage.tif");
// Create an instance of the engine
using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD))
{
// Since we have a RasterCodecs object, re-use it in the OCR engine. Although
// this demo will not use it, it is always a good practice
ocrEngine.Startup(null, null, null, LEAD_VARS.OcrLEADRuntimeDir);
// Create an OCR document
using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument())
{
// Loop through the images, add them to the document
for (int i = 0; i < 4; i++)
{
string pageFileName = Path.Combine(LEAD_VARS.ImagesDir, string.Format("Ocr{0}.tif", i + 1));
ocrDocument.Pages.AddPage(pageFileName, null);
}
Console.WriteLine("OCR Document contains {0} pages", ocrDocument.Pages.Count);
// Export the pages from index 1 to 3 to disk
using (FileStream fs = File.Create(tifFileName))
{
ocrDocument.Pages.ExportPages(1, 3, fs, RasterImageFormat.Tif, 1, 1, CodecsSavePageMode.Overwrite);
}
}
// 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:\LEADTOOLS23\Resources\Images";
public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS23\Bin\Common\OcrLEADRuntime";
}