/// <summary>
/// Load a DICOM file from an input stream, given a delegate to open the stream.
/// </summary>
/// <remarks>
/// Note: If the file does not contain DICM encoded in it, and
/// <see cref="Stream.CanSeek"/> is true for the stream returned by <paramref name="streamOpener"/>,
/// the routine will assume the file is not a Part 10 format file, and is
/// instead encoded as just a DataSet with the transfer syntax set to
/// Implicit VR Little Endian.
///
/// Also, if you are using the <see cref="DicomReadOptions.StorePixelDataReferences"/> option with
/// a <see cref="Stream"/> as opposed to simply a file name, you must use this method so that the
/// stream can be reopenened internally whenever pixel data is accessed.
/// </remarks>
/// <param name="streamOpener">A delegate that opens the stream to read from.</param>
/// <param name="stopTag">The dicom tag to stop the reading at.</param>
/// <param name="options">The dicom read options to consider.</param>
public void Load(DicomStreamOpener streamOpener, DicomTag stopTag, DicomReadOptions options)
{
Platform.CheckForNullReference(streamOpener, "streamOpener");
StreamOpener = streamOpener;
using (var stream = streamOpener.Open())
LoadCore(stream, streamOpener, stopTag, options);
}
private void LoadCore(Stream stream, DicomStreamOpener streamOpener, DicomTag stopTag, DicomReadOptions options)
{
// TODO CR (24 Jan 2014): DICOM stream read only uses tag value, so the real implementation should be the uint overload!
if (stopTag == null)
{
stopTag = new DicomTag(0xFFFFFFFF, "Bogus Tag", "BogusTag", DicomVr.NONE, false, 1, 1, false);
}
DicomStreamReader dsr;
var iStream = stream ?? streamOpener.Open();
if (iStream.CanSeek)
{
iStream.Seek(128, SeekOrigin.Begin);
if (!FileHasPart10Header(iStream))
{
if (!Flags.IsSet(options, DicomReadOptions.ReadNonPart10Files))
{
throw new DicomException(String.Format("File is not part 10 format file: {0}", Filename));
}
iStream.Seek(0, SeekOrigin.Begin);
dsr = new DicomStreamReader(iStream)
{
StreamOpener = streamOpener,
TransferSyntax = TransferSyntax.ImplicitVrLittleEndian,
Dataset = DataSet
};
DicomReadStatus stat = dsr.Read(stopTag, options);
if (stat != DicomReadStatus.Success)
{
Platform.Log(LogLevel.Error, "Unexpected error when reading file: {0}", Filename);
throw new DicomException("Unexpected read error with file: " + Filename);
}
TransferSyntax = TransferSyntax.ImplicitVrLittleEndian;
if (DataSet.Contains(DicomTags.SopClassUid))
{
MediaStorageSopClassUid = DataSet[DicomTags.SopClassUid].ToString();
}
if (DataSet.Contains(DicomTags.SopInstanceUid))
{
MediaStorageSopInstanceUid = DataSet[DicomTags.SopInstanceUid].ToString();
}
Loaded = true;
return;
}
}
else
{
// TODO CR (04 Apr 2014): this code here is almost identical to the seekable stream above, except that we use the 4CC wrapper
// we can combine these two when we trust that the wrapper works in all cases
iStream = FourCcReadStream.Create(iStream);
// Read the 128 byte header first, then check for DICM
iStream.SeekEx(128, SeekOrigin.Begin);
if (!FileHasPart10Header(iStream))
{
if (!Flags.IsSet(options, DicomReadOptions.ReadNonPart10Files))
{
throw new DicomException(String.Format("File is not part 10 format file: {0}", Filename));
}
iStream.Seek(0, SeekOrigin.Begin);
dsr = new DicomStreamReader(iStream)
{
StreamOpener = streamOpener,
TransferSyntax = TransferSyntax.ImplicitVrLittleEndian,
Dataset = DataSet
};
DicomReadStatus stat = dsr.Read(stopTag, options);
if (stat != DicomReadStatus.Success)
{
Platform.Log(LogLevel.Error, "Unexpected error when reading file: {0}", Filename);
throw new DicomException("Unexpected read error with file: " + Filename);
}
TransferSyntax = TransferSyntax.ImplicitVrLittleEndian;
if (DataSet.Contains(DicomTags.SopClassUid))
{
MediaStorageSopClassUid = DataSet[DicomTags.SopClassUid].ToString();
}
if (DataSet.Contains(DicomTags.SopInstanceUid))
{
MediaStorageSopInstanceUid = DataSet[DicomTags.SopInstanceUid].ToString();
}
Loaded = true;
return;
}
}
dsr = new DicomStreamReader(iStream)
{
TransferSyntax = TransferSyntax.ExplicitVrLittleEndian,
StreamOpener = streamOpener,
Dataset = MetaInfo
};
DicomReadStatus readStat =
dsr.Read(new DicomTag(0x0002FFFF, "Bogus Tag", "BogusTag", DicomVr.UNvr, false, 1, 1, false), options);
if (readStat != DicomReadStatus.Success)
{
Platform.Log(LogLevel.Error, "Unexpected error when reading file Meta info for file: {0}", Filename);
throw new DicomException("Unexpected failure reading file Meta info for file: " + Filename);
}
MetaInfoFileLength = dsr.EndGroupTwo + 128 + 4;
dsr.Dataset = DataSet;
dsr.TransferSyntax = TransferSyntax;
readStat = dsr.Read(stopTag, options);
if (readStat != DicomReadStatus.Success)
{
Platform.Log(LogLevel.Error, "Unexpected error ({0}) when reading file at offset {2}: {1}", readStat, Filename, dsr.BytesRead);
throw new DicomException("Unexpected failure (" + readStat + ") reading file at offset " + dsr.BytesRead + ": " + Filename);
}
Loaded = true;
}