public static void RoundTripAndRender()
{
foreach (FileInfo fi in new DirectoryInfo("..\\CompressionSamples").GetFiles("*.dcm"))
{
Console.WriteLine("Compression Test -- Filename: " + fi.Name);
DICOMData data = new DICOMData();
data.ParseFile(fi.FullName, true, new NullLogger());
TransferSyntax syntax = data.TransferSyntax;
int compressedLength = (int)data[DICOMTags.PixelData].GetDataLength(false);
data.Uncompress();
Image testImage = DICOMQuickRenderer.QuickRender(data, 0);
Assert.IsNotNull(testImage);
int uncompressedLength = (int)data[DICOMTags.PixelData].GetDataLength(false);
Assert.IsTrue(uncompressedLength > compressedLength);
if (CompressionWorker.SupportsCompression(syntax.Compression))
{
data.ChangeTransferSyntax(syntax);
int recompressedLength = (int)data[DICOMTags.PixelData].GetDataLength(false);
Assert.IsTrue(recompressedLength < uncompressedLength);
}
//data.WriteFile(fi.FullName.Replace(".dcm", "_un.dcm"));
}
}
/// <summary>
/// Checks to see if we support both the decompression (if any) and compression (if any) to perform the transfer syntax change requested.
/// If either step is not available, then this will return false, but you may still be able to do a decompression. You can check that with
/// the static methods on <see cref="DICOMSharp.Data.Compression.CompressionWorker"/>.
/// </summary>
/// <param name="newSyntax">The new transfer syntax you'd like to change to</param>
/// <returns>Whether or not the complete change can be performed.</returns>
public bool CanChangeTransferSyntax(TransferSyntax newSyntax)
{
if (!CompressionWorker.SupportsDecompression(this.TransferSyntax.Compression))
{
return(false);
}
if (!CompressionWorker.SupportsCompression(newSyntax.Compression))
{
return(false);
}
return(true);
}
public virtual void Compress()
{
if (Compressable && (_unCompressedStream != null))
{
var stream = _unCompressedStream;
stream.Position = 0;
if (StreamWrapper != null)
{
StreamWrapper.Stream = CompressionWorker.Compress(stream, Compression);
}
}
}
public virtual void DeCompress()
{
if (Compressable && (_unCompressedStream == null) && (this.Data != null))
{
this._unCompressedStream = null;
try {
_unCompressedStream = CompressionWorker.DeCompress(StreamWrapper.Stream, Compression);
_streamWrapper.Clear();
_streamWrapper = null;
_unCompressedStream.Position = 0;
} catch (Exception e) {
_unCompressedStream = null;
Trace.TraceError("StreamThing.DeCompress Error {0}", e.Message);
}
}
}
/// <summary>
/// Changes the transfer syntax used by the DICOMData structure (compressed/uncompressed, endianness, implicit/explicit VR, etc.) to a new syntax.
/// </summary>
/// <param name="newSyntax">The new transfer syntax to change to.</param>
/// <returns>Returns <c>true</c> if the change was successful, or <c>false</c> if an error was encountered.</returns>
public bool ChangeTransferSyntax(TransferSyntax newSyntax)
{
if (!CanChangeTransferSyntax(newSyntax))
{
return(false);
}
CompressionInfo oldCompression = TransferSyntax.Compression;
CompressionInfo newCompression = newSyntax.Compression;
if (oldCompression != newCompression)
{
//Is it compressed?
if (oldCompression != CompressionInfo.None)
{
//Attempt to uncompress
if (!this.Uncompress())
{
return(false);
}
}
//Need to compress it?
if (newCompression != CompressionInfo.None)
{
//Attempt to compress
if (!CompressionWorker.Compress(this, newSyntax))
{
return(false);
}
}
}
//Compressionworker will do this...
//TransferSyntax = newSyntax;
return(true);
}
/// <summary>
/// Attempts to remove any compression from the image data and changes the Transfer Syntax to Explicit VR Little Endian.
/// </summary>
/// <returns>Returns <c>true</c> if the change was successful, or <c>false</c> if an error was encountered.</returns>
public bool Uncompress()
{
return(CompressionWorker.Uncompress(this));
}
