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ExtractFramesMemory(string,List<int>) Method

Summary

Extracts the specified frames from the input file, and saves them to a new JPEG 2000 file in a byte array. This method is available in the Document/Medical Toolkits.

Syntax

C++

public byte[] ExtractFramesMemory( 
   string fileName, 
   List<int> frames 
)

  
Public Overloads Function ExtractFramesMemory( _ 
   ByVal fileName As String, _ 
   ByVal frames As List(Of Integer) _ 
) As Byte()

public: 
array<byte>^ ExtractFramesMemory(  
   String^ fileName, 
   List<int>^ frames 
)

Parameters

fileName
System.String containing the name of the JPEG 2000 file from which the frames are being extracted.

frames
Frame indices. A list of integers specifying the indices of the frames to be extracted from the input file. All indices should be 0-based.

Return Value

A byte array that contains a JPEG 2000 file with only the extracted frames.

Remarks

. This file contains only the extracted frame headers/code streams (not any obtained through the decompressing/recompressing process) so it saves processor time and memory.

This method is very suitable for server applications where multiple clients request specific frames of a JPEG 2000 file. Instead of decompressing and then recompressing the frames this method copies only the needed frame data, saving the data to a new JPEG 2000 file.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Jpeg2000; 
 
public byte[] ExtractFramesMemoryStringExample(List<int> frames) 
{ 
   Jpeg2000Engine engine = new Jpeg2000Engine(); 
 
   Jpeg2000FileInformation fileInfo = engine.GetFileInformation(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx")); 
 
   for (int i = 0; i < frames.Count; i++) 
      if (frames[i] >= fileInfo.Frame.GetLength(0)) 
         return null; 
   return engine.ExtractFramesMemory(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx"), frames); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS21\Resources\Images"; 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.Jpeg2000 
 
Private Function ExtractFramesMemoryStringExample(ByVal frames As List(Of Integer)) As Byte() 
   Dim engine As New Jpeg2000Engine() 
 
   Dim fileInfo As Jpeg2000FileInformation = engine.GetFileInformation(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx")) 
 
   For i As Integer = 0 To frames.Count - 1 
      If (frames(i) >= fileInfo.Frame.GetLength(0)) Then 
         Return Nothing 
      End If 
   Next i 
   Return engine.ExtractFramesMemory(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx"), frames) 
End Function 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\LEADTOOLS21\Resources\Images" 
End Class