FragmentJpxFile Method

Visual Basic
C#
Objective-C
Java
C++

public void FragmentJpxFile( 
   string inputFileName,
   string outputFileName,
   List<UuidUrl> urls,
   List<Fragment> fragments
)

'Declaration
 
Public Sub FragmentJpxFile( _
   ByVal inputFileName As String, _
   ByVal outputFileName As String, _
   ByVal urls As List(Of UuidUrl), _
   ByVal fragments As List(Of Fragment) _
)

'Usage
 
Dim instance As Jpeg2000Engine
Dim inputFileName As String
Dim outputFileName As String
Dim urls As List(Of UuidUrl)
Dim fragments As List(Of Fragment)
 
instance.FragmentJpxFile(inputFileName, outputFileName, urls, fragments)

public:
void FragmentJpxFile( 
   String^ inputFileName,
   String^ outputFileName,
   List<UuidUrl>^ urls,
   List<Fragment>^ fragments
)

Parameters

inputFileName

System.String containing the name of the JPX file from which frames are to be extracted.

outputFileName

System.String containing the name of the fragmented JPX file.

urls

List of UuidUrl specifying the URLs where the fragments are contained.

fragments

List of Fragment specifying the following for each fragment:

The code stream index to be fragmented
The index for the URL which contains the fragment
The offset of the first byte of the fragment within the specified URL

It is up to the user to save the fragmented code streams in their URL locations.

Fragmentation in JPX works by specifying a table of pointers to the individual fragments. Each pointer specifies three things:

The file which contains the fragment. Because multiple fragments across multiple code streams can be stored in the same file, the format encapsulates all filename/URL data into a table (the Data Reference box). Each fragment specification then references an entry in the data reference table.
The offset of the first byte of the fragment within the specified file. This offset is with respect to the first byte of the file (byte 0) and points directly to the first byte of code stream data for the fragment-- it does NOT point to the start of the box containing that fragment.
The length of the fragment, in bytes.

Fragmentation is an important feature of the JPX file format since it allows applications to implement such features as:

The capability to edit an image, resaving the changed tiles to the end of the file.
The capability to distribute the image across several disks for faster access.
The capability to distribute the image across the internet, allowing only certain customers access to the high quality or high resolution portions of the code stream.
The capability to reuse the headers from within a code stream across multiple code streams (to minimize file overhead when storing similar code streams within the same JPX file).

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.Jpeg2000

Public Sub FragmentJpxFileExample()
   Dim engine As New Jpeg2000Engine()

   Dim fileInfo As Jpeg2000FileInformation = engine.GetFileInformation(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx"))

   If (1 > fileInfo.CodeStream.GetLength(0)) Then
      Return
   End If

   Dim frames As New List(Of Integer)
   frames.Add(0)
   Dim url As New UuidUrl()
   ReDim url.Flag(2)
   url.Flag(0) = 0
   url.Flag(1) = 0
   url.Flag(2) = 0
   url.Version = 0
   Dim loaction As String = Path.Combine(LEAD_VARS.ImagesDir, "codestream.bin")
   Dim data() As Byte = Encoding.ASCII.GetBytes(loaction)
   ReDim url.Location(data.GetLength(0))
   data.CopyTo(url.Location, 0)

   Dim urls As New List(Of UuidUrl)
   urls.Add(url)
   Dim _fragment As New Fragment()
   _fragment.CodeStreamIndex = 0
   _fragment.Offset = 0
   _fragment.UrlIndex = 0
   Dim fragments As New List(Of Fragment)
   fragments.Add(_fragment)
   engine.FragmentJpxFile(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx"), Path.Combine(LEAD_VARS.ImagesDir, "Test.jpx"), urls, fragments)
End Sub

Public NotInheritable Class LEAD_VARS
Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class

using Leadtools;
using Leadtools.Codecs;
using Leadtools.Jpeg2000;

public void FragmentJpxFileExample()
{
   Jpeg2000Engine engine = new Jpeg2000Engine();

   Jpeg2000FileInformation fileInfo = engine.GetFileInformation(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx"));

   if (1 > fileInfo.CodeStream.GetLength(0))
      return;

   List<int> frames = new List<int>();
   frames.Add(0);
   UuidUrl url = new UuidUrl();
   url.Flag = new byte[3];
   url.Flag[0] = 0;
   url.Flag[1] = 0;
   url.Flag[2] = 0;
   url.Version = 0;
   String loaction = Path.Combine(LEAD_VARS.ImagesDir, "codestream.bin");
   byte[] data = Encoding.ASCII.GetBytes(loaction);
   url.Location = new byte[data.GetLength(0)];
   data.CopyTo(url.Location, 0);

   List<UuidUrl> urls = new List<UuidUrl>();
   urls.Add(url);
   Fragment fragment = new Fragment();
   fragment.CodeStreamIndex = 0;
   fragment.Offset = 0;
   fragment.UrlIndex = 0;
   List<Fragment> fragments = new List<Fragment>();
   fragments.Add(fragment);
   engine.FragmentJpxFile(Path.Combine(LEAD_VARS.ImagesDir, "image1.jpx"), Path.Combine(LEAD_VARS.ImagesDir, "Test.jpx"), urls, fragments);
}

static class LEAD_VARS
{
public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}

Target Platforms

Reference

Jpeg2000Engine Class
Jpeg2000Engine Members
AppendFrames(RasterCodecs,String,List<CompositeJpxImages>,Int32,Int32) Method
AppendGmlData
ExtractFrames
ExtractFramesMemory
ExtractFramesNativeMemory
ReadBox
ReadFrames
ReadGmlData
Compression Using LEAD and JPEG Formats
File Formats - JPEG And LEAD Compressed
Bitmaps In Memory And In Files
JPEG2000 File Comments
JPEG And LEAD File Comments
Programming with JPEG 2000 Features
JPEG 2000 Boxes