Creates a thumbnail from the specified image file.
public RasterImage ReadThumbnail(
string fileName,
CodecsThumbnailOptions options,
int pageNumber
)
Public Overloads Function ReadThumbnail( _
ByVal fileName As String, _
ByVal options As CodecsThumbnailOptions, _
ByVal pageNumber As Integer _
) As RasterImage
- (nullable LTRasterImage *)readThumbnailFromFile:(NSString *)file
options:(LTCodecsThumbnailOptions *)thumbnailOptions
pageNumber:(NSInteger)pageNumber
error:(NSError **)error
public:
RasterImage^ ReadThumbnail(
String^ fileName,
CodecsThumbnailOptions options,
int pageNumber
)
fileName
A String containing the name of the file from which the thumbnail image will be created.
options
Options for creating the thumbnail image.
pageNumber
1-based index of the page from which the thumbnail image should be created.
The RasterImage object that this method creates.
This method will always return a thumbnail image. Depending on the options passed, this method might read the stamp stored inside EXIF, CMP, JFIF and FlashPix files and return that. To read the file stamp only, use ReadStamp.
This example will read a thumbnail from a CMP file
using Leadtools;
using Leadtools.Codecs;
using Leadtools.ImageProcessing;
using Leadtools.ImageProcessing.Color;
using Leadtools.Svg;
using LeadtoolsExamples.Common;
public void ReadThumbnailExample()
{
RasterCodecs codecs = new RasterCodecs();
string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp");
// Create a thumbnail with default options
CodecsThumbnailOptions options = CodecsThumbnailOptions.Default;
options.LoadStamp = false;
RasterImage thumbnail = codecs.ReadThumbnail(srcFileName, options, 1);
Console.WriteLine("Thumbnail with default option:");
Console.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel);
thumbnail.Dispose();
// Create a thumbnail with some options
options.LoadStamp = false;
options.Width = 40;
options.Height = 80;
options.ForceSize = true;
options.MaintainAspectRatio = false;
options.BackColor = RasterColor.FromKnownColor(RasterKnownColor.LightBlue);
options.BitsPerPixel = 8;
thumbnail = codecs.ReadThumbnail(srcFileName, options, 1);
Console.WriteLine("Thumbnail with set option (size: {0} by {1}, Bits/Pixel: {2}, ForeSize: {3}",
options.Width, options.Height, options.BitsPerPixel, options.ForceSize);
Console.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel);
thumbnail.Dispose();
codecs.Dispose();
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}
Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.ImageProcessing
Imports Leadtools.ImageProcessing.Color
Imports Leadtools.Drawing
Imports Leadtools.Svg
Public Sub ReadThumbnailExample()
Dim codecs As RasterCodecs = New RasterCodecs()
Dim srcFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp")
' Create a thumbnail with default options
Dim options As CodecsThumbnailOptions = CodecsThumbnailOptions.Default
options.LoadStamp = False
Dim thumbnail As RasterImage = codecs.ReadThumbnail(srcFileName, options, 1)
Console.WriteLine("Thumbnail with default option:")
Console.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel)
thumbnail.Dispose()
' Create a thumbnail with some options
options.LoadStamp = False
options.Width = 40
options.Height = 80
options.ForceSize = True
options.MaintainAspectRatio = False
options.BackColor = RasterColor.FromKnownColor(RasterKnownColor.LightBlue)
options.BitsPerPixel = 8
thumbnail = codecs.ReadThumbnail(srcFileName, options, 1)
Console.WriteLine("Thumbnail with set option (size: {0} by {1}, Bits/Pixel: {2}, ForeSize: {3}", options.Width, options.Height, options.BitsPerPixel, options.ForceSize)
Console.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel)
thumbnail.Dispose()
codecs.Dispose()
End Sub
Public NotInheritable Class LEAD_VARS
Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class
c#[Silverlight C# Example]
using Leadtools;
using Leadtools.Codecs;
using Leadtools.Examples;
using Leadtools.ImageProcessing;
using Leadtools.ImageProcessing.Color;
using Leadtools.Windows.Media;
public void ReadThumbnailExample(Stream inStreamCmp)
{
RasterCodecs codecs = new RasterCodecs();
// Create a thumbnail with default options
CodecsThumbnailOptions options = CodecsThumbnailOptions.Default;
options.LoadStamp = false;
RasterImage thumbnail = codecs.ReadThumbnail(inStreamCmp, options, 1);
Debug.WriteLine("Thumbnail with default option:");
Debug.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel);
thumbnail.Dispose();
// Create a thumbnail with some options
options.LoadStamp = false;
options.Width = 40;
options.Height = 80;
options.ForceSize = true;
options.MaintainAspectRatio = false;
options.BackColor = new RasterColor(0x00, 0x00, 0x7F);
options.BitsPerPixel = 8;
thumbnail = codecs.ReadThumbnail(inStreamCmp, options, 1);
Debug.WriteLine("Thumbnail with set option (size: {0} by {1}, Bits/Pixel: {2}, ForeSize: {3}",
options.Width, options.Height, options.BitsPerPixel, options.ForceSize);
Debug.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel);
thumbnail.Dispose();
}
vb[Silverlight VB Example]
Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.ImageProcessing
Imports Leadtools.ImageProcessing.Color
Imports Leadtools.Windows.Media
Public Sub ReadThumbnailExample(ByVal inStreamCmp As Stream)
Dim codecs As RasterCodecs = New RasterCodecs()
' Create a thumbnail with default options
Dim options As CodecsThumbnailOptions = CodecsThumbnailOptions.Default
options.LoadStamp = False
Dim thumbnail As RasterImage = codecs.ReadThumbnail(inStreamCmp, options, 1)
Debug.WriteLine("Thumbnail with default option:")
Debug.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel)
thumbnail.Dispose()
' Create a thumbnail with some options
options.LoadStamp = False
options.Width = 40
options.Height = 80
options.ForceSize = True
options.MaintainAspectRatio = False
options.BackColor = New RasterColor(&H0, &H0, &H7F)
options.BitsPerPixel = 8
thumbnail = codecs.ReadThumbnail(inStreamCmp, options, 1)
Debug.WriteLine("Thumbnail with set option (size: {0} by {1}, Bits/Pixel: {2}, ForeSize: {3}", options.Width, options.Height, options.BitsPerPixel, options.ForceSize)
Debug.WriteLine(" Size: {0} by {1} pixels. Bits/Pixel: {2}", thumbnail.Width, thumbnail.Height, thumbnail.BitsPerPixel)
thumbnail.Dispose()
End Sub
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