DecompressJPEGFile.cs

This is a C# example on how to use gdcm::SequenceOfFragments

/*=========================================================================
Program: GDCM (Grassroots DICOM). A DICOM library
Copyright (c) 2006-2011 Mathieu Malaterre
All rights reserved.
See Copyright.txt or http://gdcm.sourceforge.net/Copyright.html for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notice for more information.
=========================================================================*/
/*
* Usage:
* $ export LD_LIBRARY_PATH=$HOME/Projects/gdcm/debug-gcc/bin
* $ mono bin/DecompressJPEGFile.exe somejpegfile.jpg
*/
using System;
using gdcm;
public class DecompressJPEGFile
{
public static int Main(string[] args)
{
string file1 = args[0];
System.IO.FileStream infile =
new System.IO.FileStream(file1, System.IO.FileMode.Open, System.IO.FileAccess.Read);
uint fsize = gdcm.PosixEmulation.FileSize(file1);
byte[] jstream = new byte[fsize];
infile.Read(jstream, 0 , jstream.Length);
Trace.DebugOn();
Image image = new Image();
image.SetNumberOfDimensions( 2 ); // important for now
DataElement pixeldata = new DataElement( new gdcm.Tag(0x7fe0,0x0010) );
// DO NOT set a ByteValue here, JPEG is a particular kind of encapsulated syntax
// in which can one cannot use a simple byte array for storage. Instead, see
// gdcm.SequenceOfFragments
//pixeldata.SetByteValue( jstream, new gdcm.VL( (uint)jstream.Length ) );
// Create a new SequenceOfFragments C++ object, store it as a SmartPointer :
SmartPtrFrag sq = SequenceOfFragments.New();
Fragment frag = new Fragment();
frag.SetByteValue( jstream, new gdcm.VL( (uint)jstream.Length) );
// Single file => single fragment
sq.AddFragment( frag );
// Pass by reference:
pixeldata.SetValue( sq.__ref__() );
// insert:
image.SetDataElement( pixeldata );
// JPEG use YBR to achieve better compression ratio by default (not RGB)
// FIXME hardcoded:
PhotometricInterpretation pi = new PhotometricInterpretation( PhotometricInterpretation.PIType.YBR_FULL );
image.SetPhotometricInterpretation( pi );
// FIXME hardcoded:
PixelFormat pixeltype = new PixelFormat(3,8,8,7);
image.SetPixelFormat( pixeltype );
// FIXME hardcoded:
image.SetTransferSyntax( new TransferSyntax( TransferSyntax.TSType.JPEGLosslessProcess14_1 ) );
image.SetDimension(0, 692);
image.SetDimension(1, 721);
// Decompress !
byte[] decompressedData = new byte[(int)image.GetBufferLength()];
image.GetBuffer(decompressedData);
// Write out the decompressed bytes
System.Console.WriteLine(image.toString());
using (System.IO.Stream stream =
System.IO.File.Open(@"/tmp/dd.raw",
System.IO.FileMode.Create))
{
System.IO.BinaryWriter writer = new System.IO.BinaryWriter(stream);
writer.Write(decompressedData);
}
return 0;
}
}
gdcm::Bitmap::SetNumberOfDimensions
void SetNumberOfDimensions(unsigned int dim)
gdcm::Bitmap::GetBufferLength
unsigned long GetBufferLength() const
gdcm::Bitmap::SetDataElement
void SetDataElement(DataElement const &de)
Definition gdcmBitmap.h:76
gdcm::Bitmap::SetDimension
void SetDimension(unsigned int idx, unsigned int dim)
gdcm::Bitmap::SetTransferSyntax
void SetTransferSyntax(TransferSyntax const &ts)
Transfer syntax.
Definition gdcmBitmap.h:69
gdcm::Bitmap::GetBuffer
bool GetBuffer(char *buffer) const
Access the raw data.
gdcm::Bitmap::SetPhotometricInterpretation
void SetPhotometricInterpretation(PhotometricInterpretation const &pi)
gdcm::Bitmap::SetPixelFormat
void SetPixelFormat(PixelFormat const &pf)
Definition gdcmBitmap.h:115
gdcm::DataElement
Class to represent a Data Element either Implicit or Explicit.
Definition gdcmDataElement.h:59
gdcm::DataElement::SetValue
void SetValue(Value const &vl)
Definition gdcmDataElement.h:100
gdcm::DataElement::SetByteValue
void SetByteValue(const char *array, VL length)
Definition gdcmDataElement.h:126
gdcm::Fragment
Class to represent a Fragment.
Definition gdcmFragment.h:44
gdcm::Image
Image.
Definition gdcmImage.h:47
gdcm::PhotometricInterpretation
Class to represent an PhotometricInterpretation.
Definition gdcmPhotometricInterpretation.h:29
gdcm::PhotometricInterpretation::PIType
PIType
Definition gdcmPhotometricInterpretation.h:31
gdcm::PixelFormat
PixelFormat.
Definition gdcmPixelFormat.h:46
gdcm::SequenceOfFragments
Class to represent a Sequence Of Fragments.
Definition gdcmSequenceOfFragments.h:32
gdcm::SequenceOfFragments::New
static SmartPointer< SequenceOfFragments > New()
Definition gdcmSequenceOfFragments.h:289
gdcm::System
Class to do system operation.
Definition gdcmSystem.h:27
gdcm::Tag
Class to represent a DICOM Data Element (Attribute) Tag (Group, Element).
Definition gdcmTag.h:39
gdcm::Trace
Trace.
Definition gdcmTrace.h:42
gdcm::Trace::DebugOn
static void DebugOn()
gdcm::TransferSyntax
Class to manipulate Transfer Syntax.
Definition gdcmTransferSyntax.h:40
gdcm::TransferSyntax::TSType
TSType
Definition gdcmTransferSyntax.h:61
gdcm::VL
Value Length.
Definition gdcmVL.h:30
gdcm
Definition gdcmASN1.h:21