StopFeedGetInformation Method

Summary

Ends a file information process in which you control the input stream.

Syntax

Objective-C

C++/CLI

Java

Python

public CodecsImageInfo StopFeedGetInformation()

- (nullable LTCodecsImageInfo *)stopFeedGetInformation:(NSError **)error

public CodecsImageInfo stopFeedGetInformation()

public: 
CodecsImageInfo^ StopFeedGetInformation();

def StopFeedGetInformation(self):

Return Value

An CodecsImageInfo object containing information about the image data provided by FeedGetInformation.

Remarks

This cleans up all the variables and buffers allocated by the StartFeedGetInformation and FeedGetInformation methods and resets all internal variables to their default settings.

You must call this method to complete the file information that was started with StartFeedGetInformation.

If you call this method before enough data is supplied to obtain the image information, it will successfully clean up the process, but will throw an exception. You should trap the error if the process is canceled purposely.

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

Example

Java

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Svg; 
 
 
public void FeedGetInformationExample() 
{ 
   RasterCodecs codecs = new RasterCodecs(); 
 
   codecs.CancelFeedGetInformation(); 
 
   string url = @"https://www.leadtools.com/images/page_graphics/leadlogo.png"; 
 
   // Create a WebRequest for the URL 
   WebRequest request = WebRequest.Create(url); 
   request.Proxy.Credentials = CredentialCache.DefaultCredentials; 
 
   // reduce the timeout to 20 sec 
   request.Timeout = 20000; 
 
   WebResponse response = request.GetResponse(); 
 
   try 
   { 
      Stream strm = response.GetResponseStream(); 
 
      // Read chunks from the stream and feed load to the image 
      codecs.StartFeedGetInformation(true, 1); 
 
      const int bufferSize = 1024; 
      byte[] buffer = new byte[bufferSize]; 
 
      bool more; 
 
      do 
      { 
         System.Windows.Forms.Application.DoEvents(); 
 
         int read = strm.Read(buffer, 0, bufferSize); 
         Debug.WriteLine("Downloading {0} bytes", read); 
         if (read > 0) 
            more = codecs.FeedGetInformation(buffer, 0, read); 
         else 
         { 
            // no more image data in the stream 
            more = false; 
         } 
      } 
      while (more); 
   } 
   finally 
   { 
      response.Close(); 
   } 
 
   CodecsImageInfo info = codecs.StopFeedGetInformation(); 
 
   // Clean up 
   codecs.Dispose(); 
 
   // Show the information 
   Debug.WriteLine(info.ToString()); 
}

 
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 feedGetInformationExample() throws IOException { 
   RasterCodecs codecs = new RasterCodecs(); 
   URL url = new URL("https://www.leadtools.com/images/page_graphics/leadlogo.png"); 
 
   // Create a WebRequest for the URL 
   HttpURLConnection con = (HttpURLConnection) url.openConnection(); 
   con.setRequestMethod("GET"); 
   con.setDefaultUseCaches(true); 
 
   // reduce the timeout to 20sec 
   con.setConnectTimeout(20000); 
   con.setReadTimeout(20000); 
   con.getResponseCode(); 
 
   FeedCallbackThunk feedLoad; 
   try { 
      InputStream inputStream = con.getInputStream(); 
 
      // Read chunks from the stream and feed load to the image 
      feedLoad = codecs.startFeedGetInformation(true, 1); 
 
      final int bufferSize = 1024; 
      byte[] buffer = new byte[bufferSize]; 
 
      boolean more; 
 
      do { 
         int read = inputStream.read(buffer, 0, bufferSize); 
         System.out.println("Downloading " + read + " bytes"); 
         if (read > 0) 
            more = feedLoad.feedGetInformation(buffer, 0, read); 
         else { 
            // no more image data in the stream 
            more = false; 
         } 
      } while (more); 
   } finally { 
      con.disconnect(); 
   } 
 
   CodecsImageInfo info = feedLoad.stopFeedGetInformation(); 
 
   // Clean up 
   codecs.dispose(); 
 
   // Show the information 
   assertTrue("The URL is invalid (null)", url != null); 
   System.out.println(info.toString()); 
}

Requirements

Target Platforms

Reference

RasterCodecs Class

RasterCodecs Members

Download our FREE evaluation

Help Version 23.0.2024.2.29

Leadtools.Codecs Assembly

Introduction

Getting Started

Namespaces

Leadtools.Codecs Namespace

Assemblies