Load(Stream,LeadRect) Method

Summary

Loads the specified rectangle from the specified image stream using default options.

Syntax

C++/CLI

Java

Python

public RasterImage Load( 
   Stream stream, 
   LeadRect tile 
)

public RasterImage load(ILeadStream stream, LeadRect tile)

public: 
RasterImage^ Load(  
   Stream^ stream, 
   LeadRect tile 
)

def Load(self,stream,tile):

Parameters

stream
A Stream containing the image data to load.

tile
A LeadRect describing the tile/area of the image to load.

Return Value

The RasterImage object that this method loads.

Remarks

This method loads a section of an image stream (any format). The section begins is defined by tile rectangle.

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.

The CodecsLoadOptions.AllPages property controls whether RasterCodecs will try to load all pages or just the first page if the image data contains multiple pages.

Example

This example will create a rectangle area from a stream containing image data.

Java

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Svg; 
 
 
 
public void LoadTileStream1Example() 
{ 
   RasterCodecs codecs = new RasterCodecs(); 
 
   string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"); 
   string destFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1_LoadTileStream1.bmp"); 
 
   FileStream fs = File.OpenRead(srcFileName); 
 
   // Get the image dimension 
   CodecsImageInfo info = codecs.GetInformation(fs, false); 
 
   // Load the lower right corner of the image 
   LeadRect rc = new LeadRect( 
      info.Width / 2, 
      info.Height / 2, 
      info.Width / 2, 
      info.Height / 2); 
 
   RasterImage image = codecs.Load(fs, rc); 
   fs.Close(); 
 
   Debug.Assert(image.Width == (info.Width / 2)); 
   Debug.Assert(image.Height == (info.Height / 2)); 
 
   // Save this image back to disk 
   codecs.Save(image, destFileName, RasterImageFormat.Bmp, 24); 
   image.Dispose(); 
 
   // Clean up 
   codecs.Dispose(); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images"; 
}

 
import java.io.*; 
import java.net.*; 
import java.nio.file.Paths; 
import java.util.*; 
import java.time.Instant; 
import java.time.Duration; 
 
import org.junit.*; 
import org.junit.runner.JUnitCore; 
import org.junit.runner.Result; 
import org.junit.runner.notification.Failure; 
import static org.junit.Assert.*; 
 
import leadtools.*; 
import leadtools.codecs.*; 
import leadtools.codecs.RasterCodecs.FeedCallbackThunk; 
import leadtools.drawing.internal.*; 
import leadtools.imageprocessing.*; 
import leadtools.imageprocessing.color.ChangeIntensityCommand; 
import leadtools.svg.*; 
 
 
public void loadTileStream1Example() throws IOException { 
   final String LEAD_VARS_IMAGES_DIR = "C:\\LEADTOOLS23\\Resources\\Images"; 
   RasterCodecs codecs = new RasterCodecs(); 
 
   String srcFileName = combine(LEAD_VARS_IMAGES_DIR, "Image1.cmp"); 
   String destFileName = combine(LEAD_VARS_IMAGES_DIR, "Image1_LoadTileStream1.bmp"); 
 
   ILeadStream fs = LeadStreamFactory.create(srcFileName); 
 
   // Get the image dimension 
   CodecsImageInfo info = codecs.getInformation(fs, false); 
 
   // Load the lower right corner of the image 
   LeadRect rc = new LeadRect( 
         info.getWidth() / 2, 
         info.getHeight() / 2, 
         info.getWidth() / 2, 
         info.getHeight() / 2); 
 
   RasterImage image = codecs.load(fs, rc); 
   fs.close(); 
 
   assertTrue(image.getWidth() == (info.getWidth() / 2)); 
   assertTrue(image.getHeight() == (info.getHeight() / 2)); 
 
   // Save this image back to disk 
   codecs.save(image, destFileName, RasterImageFormat.BMP, 24); 
   assertTrue("File was unsuccessfully saved to" + destFileName, (new File(destFileName)).exists()); 
   System.out.println("File is saved to" + destFileName); 
 
   // Clean up 
   codecs.dispose(); 
   image.dispose(); 
}