Public Overloads Function Load( _
   ByVal stream As Stream, _
   ByVal bitsPerPixel As Integer, _
   ByVal order As CodecsLoadByteOrder, _
   ByVal firstPage As Integer, _
   ByVal lastPage As Integer _
) As RasterImage

Visual Basic (Usage)	Copy Code
Dim instance As RasterCodecs Dim stream As Stream Dim bitsPerPixel As Integer Dim order As CodecsLoadByteOrder Dim firstPage As Integer Dim lastPage As Integer Dim value As RasterImage   value = instance.Load(stream, bitsPerPixel, order, firstPage, lastPage)

public RasterImage Load( 
   Stream stream,
   int bitsPerPixel,
   CodecsLoadByteOrder order,
   int firstPage,
   int lastPage
)

public:
RasterImage Load( 
   Stream^ stream,
   int bitsPerPixel,
   CodecsLoadByteOrder order,
   int firstPage,
   int lastPage
) 

Parameters

stream

A Stream containing the the image data to load.

bitsPerPixel

Resulting image pixel depth. Valid values are:

value	meaning
0	Keep the original file's pixel depth (Do not convert).
1 to 8	The specified bits per pixel in the resulting image.
12	12 bits per pixel in the resulting image.
16	16 bits per pixel in the resulting image.
24	24 bits per pixel in the resulting image.
32	32 bits per pixel in the resulting image.
48	48 bits per pixel in the resulting image.
64	64 bits per pixel in the resulting image.

order

Color order for 16-, 24-, 32-, 48-, and 64-bit images. If the resulting image is less than 16 bits per pixel, this will have no effect since palletized images have no order. The following are valid values.

Value	Meaning
CodecsLoadByteOrder.Rgb	Red, green, and blue color order in memory
CodecsLoadByteOrder.Bgr	Blue, green, and red color order in memory
CodecsLoadByteOrder.Gray	12 or 16-bit grayscale image. 12 and 16-bit grayscale images are only supported in the Document/Medical Imaging editions.
CodecsLoadByteOrder.RgbOrGray	Load the image as red, green, blue OR as a 12 or 16-bit grayscale image. 12 and 16-bit grayscale images are supported in the Document/Medical Imaging editions
CodecsLoadByteOrder.BgrOrGray	Load the image as blue, green, red OR as a 12 or 16-bit grayscale image. 12 and 16-bit grayscale images are supported in the Document/Medical Imaging editions
CodecsLoadByteOrder.Romm	ROMM order. ROMM only supports 24 and 48-bit images
CodecsLoadByteOrder.BgrOrGrayOrRomm	Load the image as red, green, blue OR as a 12 or 16-bit grayscale image OR as ROMM. 12 and 16-bit grayscale images are supported in the Document/Medical Imaging editions only. ROMM only supports 24 and 48-bit color images.

firstPage

1-based index of the first page to load.

lastPage

The 1-based index of the last page to load. Must be greater than or equal to firstPage. You can pass -1 to load from firstPage to the last page in the stream.

Return Value

This example will show how to load an image using different bits/pixel and color order than that saved on disk. Also, it will show how to load a single page or a group of pages from a multipage file All loading operation uses a stream instead of a file on disk

Visual Basic

Copy Code

Public Sub LoadStream2Example()    RasterCodecs.Startup()    Dim codecs As RasterCodecs = New RasterCodecs()    Dim multiPageFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "Eye.gif"    Dim fs As FileStream = File.OpenRead(multiPageFileName)    ' Get the file information (we are interested in the number of pages)    Dim info As CodecsImageInfo = codecs.GetInformation(fs, True)    Console.WriteLine("Number of pages according to info: {0}", info.TotalPages)    ' Load the first page    Dim first As Integer = 1    Dim last As Integer = 1    Dim image As RasterImage = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, first, last)    Console.WriteLine("Loading pages {0} to {1}, pages loaded = {2}", first, last, image.PageCount)    Debug.Assert(image.PageCount = last - first + 1)    image.Dispose()    ' Load the second page    first = 2    last = 2    image = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, first, last)    Console.WriteLine("Loading pages {0} to {1}, pages loaded = {2}", first, last, image.PageCount)    Debug.Assert(image.PageCount = last - first + 1)    image.Dispose()    ' Load from the second page to page before last    first = 2    last = info.TotalPages - 1    image = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, first, last)    Console.WriteLine("Loading pages {0} to {1}, pages loaded = {2}", first, last, image.PageCount)    Debug.Assert(image.PageCount = last - first + 1)    image.Dispose()    ' load all the pages    image = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, 1, -1)    Console.WriteLine("Loading all pages, pages loaded = {0}", image.PageCount)    Debug.Assert(image.PageCount = info.TotalPages)    image.Dispose()    fs.Close()    ' Clean up    codecs.Dispose()    RasterCodecs.Shutdown() End Sub

C#

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public void LoadStream2Example()  {     RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();       string multiPageFileName = LeadtoolsExamples.Common.ImagesPath.Path + "Eye.gif";       FileStream fs = File.OpenRead(multiPageFileName);       // Get the file information (we are interested in the number of pages)     CodecsImageInfo info = codecs.GetInformation(fs, true);     Console.WriteLine("Number of pages according to info: {0}", info.TotalPages);       // Load the first page     int first = 1;     int last = 1;     RasterImage image = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, first, last);     Console.WriteLine("Loading pages {0} to {1}, pages loaded = {2}", first, last, image.PageCount);     Debug.Assert(image.PageCount == last - first + 1);     image.Dispose();       // Load the second page     first = 2;     last = 2;     image = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, first, last);     Console.WriteLine("Loading pages {0} to {1}, pages loaded = {2}", first, last, image.PageCount);     Debug.Assert(image.PageCount == last - first + 1);     image.Dispose();       // Load from the second page to page before last     first = 2;     last = info.TotalPages - 1;     image = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, first, last);     Console.WriteLine("Loading pages {0} to {1}, pages loaded = {2}", first, last, image.PageCount);     Debug.Assert(image.PageCount == last - first + 1);     image.Dispose();       // load all the pages     image = codecs.Load(fs, 0, CodecsLoadByteOrder.BgrOrGray, 1, -1);     Console.WriteLine("Loading all pages, pages loaded = {0}", image.PageCount);     Debug.Assert(image.PageCount == info.TotalPages);     image.Dispose();       fs.Close();       // Clean up     codecs.Dispose();     RasterCodecs.Shutdown();  }

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

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 options parameters before calling this method.

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

For supported formats, refer to Summary of All Supported Image 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.

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

Reference