FeedLoad(IntPtr,int) Method

Summary

Supplies unmanaged memory image data to the file-load process from a buffer that you provide.

Syntax

Objective-C

C++/CLI

Python

public void FeedLoad( 
   IntPtr data, 
   int length 
)

- (BOOL)feedLoad:(const unsigned char *)buffer length:(NSUInteger)length error:(NSError **)error 
- (BOOL)feedLoadData:(NSData *)data length:(NSUInteger)length error:(NSError **)error

public: 
void FeedLoad(  
   IntPtr data, 
   int length 
)

def FeedLoad(self,data,length):

Parameters

data
The image file unmanaged memory data.

length
Total size (in bytes) of the image data.

Remarks

Use this method with the StartFeedLoad and StopFeedLoad methods.

For a description of how the methods relate to each other, refer to StartFeedLoad.

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.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Svg; 
 
 
public void FeedLoadExample() 
{ 
   RasterCodecs codecs = new RasterCodecs(); 
 
   codecs.CancelFeedLoad(); 
 
   string url = @"https://www.leadtools.com/images/page_graphics/leadlogo.png"; 
   string destFileName = Path.Combine(LEAD_VARS.ImagesDir, "FeedLoad.bmp"); 
 
   // Create a WebRequest for the URL 
   WebRequest request = WebRequest.Create(url); 
   request.Proxy.Credentials = CredentialCache.DefaultCredentials; 
 
   // reduce the timeout to 20sec 
   request.Timeout = 20000; 
 
   WebResponse response = request.GetResponse(); 
   try 
   { 
      Stream strm = response.GetResponseStream(); 
 
      // Read chunks from the stream and feed load to the image 
      codecs.StartFeedLoad(0, CodecsLoadByteOrder.BgrOrGray); 
 
      const int bufferSize = 1024; 
      byte[] buffer = new byte[bufferSize]; 
 
      int read; 
 
      do 
      { 
         System.Windows.Forms.Application.DoEvents(); 
 
         read = strm.Read(buffer, 0, bufferSize); 
         Debug.WriteLine("Downloading {0} bytes", read); 
         if (read > 0) 
            codecs.FeedLoad(buffer, 0, read); 
      } 
      while (read > 0); 
   } 
   finally 
   { 
      response.Close(); 
   } 
 
   RasterImage image = codecs.StopFeedLoad(); 
 
   // Save the image to disk 
   codecs.Save(image, destFileName, RasterImageFormat.Bmp, 24); 
   image.Dispose(); 
 
   // Clean up 
   codecs.Dispose(); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}