/// <summary>
 /// Contructor from a <see cref="DicomCompressedPixelData"/> instance.
 /// </summary>
 /// <param name="compressedPixelData"></param>
 public DicomUncompressedPixelData(DicomCompressedPixelData compressedPixelData)
     : base(compressedPixelData)
 {
     if (BitsAllocated > 8)
     {
         _pd = new DicomElementOw(DicomTags.PixelData);
     }
     else
     {
         var pdTag = DicomTagDictionary.GetDicomTag(DicomTags.PixelData);
         var obTag = new DicomTag(DicomTags.PixelData, pdTag.Name, pdTag.VariableName, DicomVr.OBvr, pdTag.MultiVR, pdTag.VMLow, pdTag.VMHigh, pdTag.Retired);
         _pd = new DicomElementOb(obTag);
     }
     InitializeFrameData(this, _pd);
 }
Example #2
0
        public void ChangeTransferSyntax(TransferSyntax newTransferSyntax, IDicomCodec inputCodec, DicomCodecParameters inputParameters)
        {
            IDicomCodec          codec      = inputCodec;
            DicomCodecParameters parameters = inputParameters;

            if (newTransferSyntax.Encapsulated && TransferSyntax.Encapsulated)
            {
                throw new DicomCodecException("Source and destination transfer syntaxes encapsulated");
            }

            if (newTransferSyntax.Encapsulated)
            {
                if (codec == null)
                {
                    codec = DicomCodecRegistry.GetCodec(newTransferSyntax);
                    if (codec == null)
                    {
                        LogAdapter.Logger.ErrorWithFormat("Unable to get registered codec for {0}", newTransferSyntax);
                        throw new DicomCodecException("No registered codec for: " + newTransferSyntax.Name);
                    }
                }
                if (parameters == null)
                {
                    parameters = DicomCodecRegistry.GetCodecParameters(newTransferSyntax, DataSet);
                }

                DicomElement pixelData;
                if (DataSet.TryGetAttribute(DicomTags.PixelData, out pixelData))
                {
                    if (pixelData.IsNull)
                    {
                        throw new DicomCodecException("Sop pixel data has no valid value and cannot be compressed.");
                    }

                    new OverlayPlaneModuleIod(DataSet).ExtractEmbeddedOverlays();

                    var pd = new DicomUncompressedPixelData(DataSet);
                    using (var pixelStream = ((DicomElementBinary)pixelData).AsStream())
                    {
                        //Before compression, make the pixel data more "typical", so it's harder to mess up the codecs.
                        //NOTE: Could combine mask and align into one method so we're not iterating twice, but I prefer having the methods separate.
                        if (DicomUncompressedPixelData.RightAlign(pixelStream, pd.BitsAllocated, pd.BitsStored, pd.HighBit))
                        {
                            var newHighBit = (ushort)(pd.HighBit - pd.LowBit);
                            LogAdapter.Logger.WarnWithFormat("Right aligned pixel data (High Bit: {0}->{1}).", pd.HighBit, newHighBit);

                            pd.HighBit = newHighBit;                             //correct high bit after right-aligning.
                            DataSet[DicomTags.HighBit].SetUInt16(0, newHighBit);
                        }
                        if (DicomUncompressedPixelData.ZeroUnusedBits(pixelStream, pd.BitsAllocated, pd.BitsStored, pd.HighBit))
                        {
                            LogAdapter.Logger.Warning("Zeroed some unused bits before compression.");
                        }
                    }

                    // Set transfer syntax before compression, the codecs need it.
                    var fragments = new DicomCompressedPixelData(pd)
                    {
                        TransferSyntax = newTransferSyntax
                    };
                    codec.Encode(pd, fragments, parameters);
                    fragments.UpdateMessage(this);

                    //TODO: should we validate the number of frames in the compressed data?
                    if (!DataSet.TryGetAttribute(DicomTags.PixelData, out pixelData) || pixelData.IsNull)
                    {
                        throw new DicomCodecException("Sop has no pixel data after compression.");
                    }
                }
                else
                {
                    //A bit cheap, but check for basic image attributes - if any exist
                    // and are non-empty, there should probably be pixel data too.

                    DicomElement element;
                    if (DataSet.TryGetAttribute(DicomTags.Rows, out element) && !element.IsNull)
                    {
                        throw new DicomCodecException("Suspect Sop appears to be an image (Rows is non-empty), but has no pixel data.");
                    }

                    if (DataSet.TryGetAttribute(DicomTags.Columns, out element) && !element.IsNull)
                    {
                        throw new DicomCodecException("Suspect Sop appears to be an image (Columns is non-empty), but has no pixel data.");
                    }

                    TransferSyntax = newTransferSyntax;
                }
            }
            else
            {
                if (codec == null)
                {
                    codec = DicomCodecRegistry.GetCodec(TransferSyntax);
                    if (codec == null)
                    {
                        LogAdapter.Logger.ErrorWithFormat("Unable to get registered codec for {0}", TransferSyntax);

                        throw new DicomCodecException("No registered codec for: " + TransferSyntax.Name);
                    }

                    if (parameters == null)
                    {
                        parameters = DicomCodecRegistry.GetCodecParameters(TransferSyntax, DataSet);
                    }
                }

                DicomElement pixelData;
                if (DataSet.TryGetAttribute(DicomTags.PixelData, out pixelData))
                {
                    if (pixelData.IsNull)
                    {
                        throw new DicomCodecException("Sop pixel data has no valid value and cannot be decompressed.");
                    }

                    var fragments = new DicomCompressedPixelData(DataSet);
                    var pd        = new DicomUncompressedPixelData(fragments);

                    codec.Decode(fragments, pd, parameters);

                    pd.TransferSyntax = TransferSyntax.ExplicitVrLittleEndian;
                    TransferSyntax    = TransferSyntax.ExplicitVrLittleEndian;

                    pd.UpdateMessage(this);

                    //TODO: should we validate the number of frames in the decompressed data?
                    if (!DataSet.TryGetAttribute(DicomTags.PixelData, out pixelData) || pixelData.IsNull)
                    {
                        throw new DicomCodecException("Sop has no pixel data after decompression.");
                    }
                }
                else
                {
                    //NOTE: doing this for consistency, really.
                    DicomElement element;
                    if (DataSet.TryGetAttribute(DicomTags.Rows, out element) && !element.IsNull)
                    {
                        throw new DicomCodecException("Suspect Sop appears to be an image (Rows is non-empty), but has no pixel data.");
                    }

                    if (DataSet.TryGetAttribute(DicomTags.Columns, out element) && !element.IsNull)
                    {
                        throw new DicomCodecException("Suspect Sop appears to be an image (Columns is non-empty), but has no pixel data.");
                    }

                    TransferSyntax = TransferSyntax.ExplicitVrLittleEndian;
                }
            }
        }