Load(Uri,int) Method

Summary

Loads a page from the specified image URL using default options.

Syntax

C++

public RasterImage Load( 
   Uri uri, 
   int pageNumber 
)

Public Overloads Function Load( _ 
   ByVal uri As Uri, _ 
   ByVal pageNumber As Integer _ 
) As RasterImage

public: 
RasterImage^ Load(  
   Uri^ uri, 
   int pageNumber 
)

Parameters

uri
The Uri containing the input image data.

pageNumber
1-based index to the page number to load.

Return Value

The RasterImage object that this method loads.

Remarks

The file can be in any supported image file format and bits per pixel, whether compressed or uncompressed.

This method will load a single page from a multipage file. The resulting image will have the same bits/pixel and color order value of the image as it was stored in the file.

LEADTOOLS will attempt to load corrupted files so you can see at least a portion of the image. For these images, the load methods succeed, but LoadStatus will return an error code.

Use the CodecsLoadOptions class to set up other load option parameters before calling this method.

Support for 12 and 16-bit grayscale, and 48 and 64-bit color images is only available in the Document/Medical Imaging editions.

For supported formats, refer to Summary of All Supported File Formats.

LEADTOOLS loads all PDF files as Raster PDF uncompressed RasterImageFormat.RasPdf, regardless of the compression and color space used when saving the file.

LEADTOOLS supports the following URI schemes:

Scheme	Description
UriSchemeFile	Specifies that the URI is a disk file in local machine or universal naming convention (UNC) path.
UriSchemeHttp	Specifies that the URI is accessed through the Hypertext Transfer Protocol (HTTP).
UriSchemeHttps	Specifies that the URI is accessed through the Secure Hypertext Transfer Protocol (HTTPS).
UriSchemeFtp	Specifies that the URI is accessed through the File Transfer Protocol (FTP).

If uri points to a resource in a UriSchemeHttp, UriSchemeHttps or UriSchemeFtp, then this RasterCodecs will attempt to download image data in an iterative fashion by creating a temporary buffer. The size of this buffer can be determined and changed by setting up the UriOperationBufferSize prior to calling this method.

For authenticity and proxy settings, refer to UriOperationCredentials and UriOperationProxy.

Example

This example will query the number of pages from a URI and then load them.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Svg; 
using LeadtoolsExamples.Common; 
 
private static void LoadPagesFromUriTest(Uri uri) 
{ 
   // Create a new RasterCodecs instance 
   using (RasterCodecs rasterCodecs = new RasterCodecs()) 
   { 
      // Get the number of pages 
      int pageCount = rasterCodecs.GetTotalPages(uri); 
      Console.WriteLine("Number of pages in the file is {0}", pageCount); 
 
      // Load all pages 
      for (int pageNumber = 1; pageNumber <= pageCount; pageNumber++) 
      { 
         using (RasterImage rasterImage = rasterCodecs.Load(uri, pageNumber)) 
         { 
            Console.WriteLine("Page {0} loaded", pageNumber); 
         } 
      } 
   } 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing 
Imports Leadtools.ImageProcessing.Color 
Imports Leadtools.Drawing 
Imports Leadtools.Svg 
 
Private Shared Sub LoadPagesFromUriTest(uri As Uri) 
   ' Create a new RasterCodecs instance 
   Using rasterCodecs As New RasterCodecs() 
      ' Get the number of pages 
      Dim pageCount As Integer = rasterCodecs.GetTotalPages(uri) 
      Console.WriteLine("Number of pages in the file is {0}", pageCount) 
 
      ' Load all pages 
      For pageNumber As Integer = 1 To pageCount 
         Using rasterImage As RasterImage = rasterCodecs.Load(uri, pageNumber) 
            Console.WriteLine("Page {0} loaded", pageNumber) 
         End Using 
      Next 
   End Using 
End Sub