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dcmjpeg: a compression/decompression library and utility apps

This module contains classes that convert between uncompressed and JPEG compressed representations (transfer syntaxes) of a DICOM image object. Both lossless and lossy JPEG processes are supported. This module implements a family of codecs that are derived from class DcmCodec and can be registered in the codec list maintained in module dcmdata.

The main interface classes are:

Tools

This module contains the following command line tools:

Examples

The following example shows how to compress a DICOM image file with lossless JPEG:

DJEncoderRegistration::registerCodecs(); // register JPEG codecs
DcmFileFormat fileformat;
if (fileformat.loadFile("test.dcm").good())
{
 DcmDataset *dataset = fileformat.getDataset();
 DcmItem *metaInfo = fileformat.getMetaInfo();
 DJ_RPLossless params; // codec parameters, we use the defaults

 // this causes the lossless JPEG version of the dataset to be created
 if (dataset->chooseRepresentation(EXS_JPEGProcess14SV1, &params).good() &&
      dataset->canWriteXfer(EXS_JPEGProcess14SV1))
  {
 // store in lossless JPEG format
    fileformat.saveFile("test_jpeg.dcm", EXS_JPEGProcess14SV1);
  }
}
DJEncoderRegistration::cleanup(); // deregister JPEG codecs

The following example shows how to decompress a JPEG-compressed DICOM image file:

DJDecoderRegistration::registerCodecs(); // register JPEG codecs
DcmFileFormat fileformat;
if (fileformat.loadFile("test_jpeg.dcm").good())
{
 DcmDataset *dataset = fileformat.getDataset();

 // decompress data set if compressed
 if (dataset->chooseRepresentation(EXS_LittleEndianExplicit, NULL).good() &&
      dataset->canWriteXfer(EXS_LittleEndianExplicit))
  {
    fileformat.saveFile("test_decompressed.dcm", EXS_LittleEndianExplicit);
  }
}
DJDecoderRegistration::cleanup(); // deregister JPEG codecs