public FusionOverlayImageGraphic(FusionOverlayFrameData fusionOverlayFrameData)
: base(fusionOverlayFrameData._overlayFrameParams.Rows, fusionOverlayFrameData._overlayFrameParams.Columns,
fusionOverlayFrameData._overlayFrameParams.BitsAllocated, fusionOverlayFrameData._overlayFrameParams.BitsStored, fusionOverlayFrameData._overlayFrameParams.HighBit,
fusionOverlayFrameData._overlayFrameParams.IsSigned, fusionOverlayFrameData._overlayFrameParams.IsInverted,
fusionOverlayFrameData._overlayFrameParams.RescaleSlope, fusionOverlayFrameData._overlayFrameParams.RescaleIntercept,
fusionOverlayFrameData.GetPixelData)
{
// this image graphic needs to keep a transient reference on the slice, otherwise it could get disposed before we do!
_overlayFrameData = fusionOverlayFrameData.CreateTransientReference();
if (fusionOverlayFrameData.OverlayData.Modality == @"PT" && RescaleSlope < 1.0/(1 << BitsStored))
{
// some PET images have such a small slope that all stored pixel values map to one single value post-modality LUT
// we detect this condition here and apply the inverse of the modality LUT as a normalization function for VOI purposes
// http://groups.google.com/group/comp.protocols.dicom/browse_thread/thread/8930b159cb2a8e73?pli=1
NormalizationLut = new InvertedLinearLut(RescaleSlope, RescaleIntercept);
}
}
/// <summary>
/// Cloning constructor.
/// </summary>
/// <param name="source">The source object from which to clone.</param>
/// <param name="context">The cloning context object.</param>
private InvertedLinearLut(InvertedLinearLut source, ICloningContext context)
{
_rescaleSlope = source._rescaleSlope;
_rescaleIntercept = source._rescaleIntercept;
}
/// <summary>
/// Cloning constructor.
/// </summary>
/// <param name="source">The source object from which to clone.</param>
/// <param name="context">The cloning context object.</param>
private InvertedLinearLut(InvertedLinearLut source, ICloningContext context)
{
_rescaleSlope = source._rescaleSlope;
_rescaleIntercept = source._rescaleIntercept;
}
