''' <summary>
''' Extracts Hounsfield values from DICOM frame.
''' </summary>
Public Class ExtractHounsfieldValuesFromDicomFrame

    ''' <summary>
    ''' Returns the Hounsfield values of DICOM frame.
    ''' </summary>
    ''' <param name="frame">The DICOM frame.</param>
    ''' <returns>
    ''' The Hounsfield values.
    ''' </returns>
    Public Shared Function GetHounsfieldValuesOfFrame(frame As Vintasoft.Imaging.Codecs.ImageFiles.Dicom.DicomFrame) As Long(,)
        ' create DICOM decoding settings
        Dim settings As New Vintasoft.Imaging.Codecs.Decoders.DicomDecodingSettings(True, False, Vintasoft.Imaging.Codecs.ImageFiles.Dicom.DicomImagePixelFormat.Source)

        ' load image of DICOM frame
        Using image As Vintasoft.Imaging.VintasoftImage = frame.GetImage(settings, Nothing)
            ' pixel matrix of the image
            Dim pixelValues As Long(,) = New Long(image.Width - 1, image.Height - 1) {}

            ' open the pixel manipulator
            Using pixelManipulator As Vintasoft.Imaging.PixelManipulator = image.OpenPixelManipulator()
                ' lock image pixels
                Dim lockRectangle As New System.Drawing.Rectangle(0, 0, image.Width, image.Height)
                pixelManipulator.LockPixels(lockRectangle, Vintasoft.Imaging.BitmapLockMode.Read)

                Dim stride As Integer = pixelManipulator.Stride

                ' get significant channel of image
                Dim significantChannel As Vintasoft.Imaging.ChannelFormat = GetSignificantChannel(image)

                ' get count of bits per pixel
                Dim bitsPerPixel As Integer = image.ColorChannelsFormat.BitsPerPixel
                ' get a value indicating whether pixel values are unsigned
                Dim isUnsigned As Boolean = significantChannel.IsUnsigned

                ' read image pixels
                For y As Integer = 0 To image.Height - 1
                    ' read row
                    Dim row As Byte() = pixelManipulator.ReadRowData(y)

                    Select Case bitsPerPixel
                        Case 8
                            If isUnsigned Then
                                For x As Integer = 0 To image.Width - 1
                                    pixelValues(x, y) = row(x)
                                Next
                            Else
                                For x As Integer = 0 To image.Width - 1
                                    pixelValues(x, y) = CSByte(row(x))
                                Next
                            End If
                            Exit Select

                        Case 16
                            If isUnsigned Then
                                Dim x As Integer = 0, rowIndex As Integer = 0
                                While x < image.Width
                                    pixelValues(x, y) = CUShort(row(rowIndex) Or (row(rowIndex + 1) << 8))
                                    x += 1
                                    rowIndex += 2
                                End While
                            Else
                                Dim x As Integer = 0, rowIndex As Integer = 0
                                While x < image.Width
                                    pixelValues(x, y) = CShort(row(rowIndex) Or (row(rowIndex + 1) << 8))
                                    x += 1
                                    rowIndex += 2
                                End While
                            End If
                            Exit Select

                        Case 32
                            If isUnsigned Then
                                Dim x As Integer = 0, rowIndex As Integer = 0
                                While x < image.Width
                                    pixelValues(x, y) = CUInt(row(rowIndex) Or (row(rowIndex + 1) << 8) Or (row(rowIndex + 2) << 16) Or (row(rowIndex + 3) << 24))
                                    x += 1
                                    rowIndex += 4
                                End While
                            Else
                                Dim x As Integer = 0, rowIndex As Integer = 0
                                While x < image.Width
                                    pixelValues(x, y) = CInt(row(rowIndex) Or (row(rowIndex + 1) << 8) Or (row(rowIndex + 2) << 16) Or (row(rowIndex + 3) << 24))
                                    x += 1
                                    rowIndex += 4
                                End While
                            End If
                            Exit Select
                        Case Else

                            Throw New System.NotImplementedException()
                    End Select
                Next
            End Using

            Return pixelValues
        End Using
    End Function

    ''' <summary>
    ''' Returns the significant channel of image.
    ''' </summary>
    ''' <param name="image">The image.</param>
    ''' <returns>
    ''' The significant channel.
    ''' </returns>
    ''' <exception cref="System.InvalidOperationException">The significant channel does not exist.</exception>
    Private Shared Function GetSignificantChannel(image As Vintasoft.Imaging.VintasoftImage) As Vintasoft.Imaging.ChannelFormat
        For Each channel As Vintasoft.Imaging.ChannelFormat In image.ColorChannelsFormat.Channels
            If channel.IsSignificant Then
                Return channel
            End If
        Next

        Throw New System.InvalidOperationException("The significant channel does not exist.")
    End Function

End Class

/// <summary>
/// Extracts Hounsfield values from DICOM frame.
/// </summary>
public class ExtractHounsfieldValuesFromDicomFrame
{

    /// <summary>
    /// Returns the Hounsfield values of DICOM frame.
    /// </summary>
    /// <param name="frame">The DICOM frame.</param>
    /// <returns>
    /// The Hounsfield values.
    /// </returns>
    public static long[,] GetHounsfieldValuesOfFrame(Vintasoft.Imaging.Codecs.ImageFiles.Dicom.DicomFrame frame)
    {
        // create DICOM decoding settings
        Vintasoft.Imaging.Codecs.Decoders.DicomDecodingSettings settings =
            new Vintasoft.Imaging.Codecs.Decoders.DicomDecodingSettings(
                true, false, Vintasoft.Imaging.Codecs.ImageFiles.Dicom.DicomImagePixelFormat.Source);

        // load image of DICOM frame
        using (Vintasoft.Imaging.VintasoftImage image = frame.GetImage(settings, null))
        {
            // pixel matrix of the image
            long[,] pixelValues = new long[image.Width, image.Height];

            // open the pixel manipulator
            using (Vintasoft.Imaging.PixelManipulator pixelManipulator = image.OpenPixelManipulator())
            {
                // lock image pixels
                System.Drawing.Rectangle lockRectangle = new System.Drawing.Rectangle(0, 0, image.Width, image.Height);
                pixelManipulator.LockPixels(lockRectangle, Vintasoft.Imaging.BitmapLockMode.Read);

                int stride = pixelManipulator.Stride;

                // get significant channel of image
                Vintasoft.Imaging.ChannelFormat significantChannel = GetSignificantChannel(image);

                // get count of bits per pixel
                int bitsPerPixel = image.ColorChannelsFormat.BitsPerPixel;
                // get a value indicating whether pixel values are unsigned
                bool isUnsigned = significantChannel.IsUnsigned;

                // read image pixels
                for (int y = 0; y < image.Height; y++)
                {
                    // read row
                    byte[] row = pixelManipulator.ReadRowData(y);

                    switch (bitsPerPixel)
                    {
                        case 8:
                            if (isUnsigned)
                            {
                                for (int x = 0; x < image.Width; x++)
                                    pixelValues[x, y] = row[x];
                            }
                            else
                            {
                                for (int x = 0; x < image.Width; x++)
                                    pixelValues[x, y] = (sbyte)row[x];
                            }
                            break;

                        case 16:
                            if (isUnsigned)
                            {
                                for (int x = 0, rowIndex = 0; x < image.Width; x++, rowIndex += 2)
                                    pixelValues[x, y] = (ushort)(row[rowIndex] | (row[rowIndex + 1] << 8));
                            }
                            else
                            {
                                for (int x = 0, rowIndex = 0; x < image.Width; x++, rowIndex += 2)
                                    pixelValues[x, y] = (short)(row[rowIndex] | (row[rowIndex + 1] << 8));
                            }
                            break;

                        case 32:
                            if (isUnsigned)
                            {
                                for (int x = 0, rowIndex = 0; x < image.Width; x++, rowIndex += 4)
                                {
                                    pixelValues[x, y] = (uint)(row[rowIndex] |
                                        (row[rowIndex + 1] << 8) |
                                        (row[rowIndex + 2] << 16) |
                                        (row[rowIndex + 3] << 24));
                                }
                            }
                            else
                            {
                                for (int x = 0, rowIndex = 0; x < image.Width; x++, rowIndex += 4)
                                {
                                    pixelValues[x, y] = (int)(row[rowIndex] |
                                        (row[rowIndex + 1] << 8) |
                                        (row[rowIndex + 2] << 16) |
                                        (row[rowIndex + 3] << 24));
                                }
                            }
                            break;

                        default:
                            throw new System.NotImplementedException();
                    }
                }
            }

            return pixelValues;
        }
    }

    /// <summary>
    /// Returns the significant channel of image.
    /// </summary>
    /// <param name="image">The image.</param>
    /// <returns>
    /// The significant channel.
    /// </returns>
    /// <exception cref="System.InvalidOperationException">The significant channel does not exist.</exception>
    private static Vintasoft.Imaging.ChannelFormat GetSignificantChannel(Vintasoft.Imaging.VintasoftImage image)
    {
        foreach (Vintasoft.Imaging.ChannelFormat channel in image.ColorChannelsFormat.Channels)
        {
            if (channel.IsSignificant)
                return channel;
        }

        throw new System.InvalidOperationException("The significant channel does not exist.");
    }

}