private static double CalculateMean
(
RectangleF roiBoundingBox,
GrayscalePixelData pixelData,
IModalityLut modalityLut,
IsPointInRoiDelegate isPointInRoi
)
{
double sum = 0;
int pixelCount = 0;
var boundingBox = RectangleUtilities.RoundInflate(RectangleUtilities.ConvertToPositiveRectangle(roiBoundingBox));
pixelData.ForEachPixel(
boundingBox.Left,
boundingBox.Top,
boundingBox.Right,
boundingBox.Bottom,
delegate(int i, int x, int y, int pixelIndex)
{
if (isPointInRoi(x, y))
{
++pixelCount;
// Make sure we run the raw pixel through the modality LUT
// when doing the calculation. Note that the modality LUT
// can be something other than a rescale intercept, so we can't
// just run the mean through the LUT.
int storedValue = pixelData.GetPixel(pixelIndex);
double realValue = modalityLut != null ? modalityLut[storedValue] : storedValue;
sum += realValue;
}
});
if (pixelCount == 0)
return 0;
return sum/pixelCount;
}
public void ForEachPixel()
{
int columns = 5;
int rows = 4;
int bitsAllocated = 16;
int bitsStored = 16;
int highBit = 15;
bool isSigned = true;
int samplesPerPixel = 1;
int imageSize = columns * rows * bitsAllocated / 8 * samplesPerPixel;
byte[] pixelData = new byte[imageSize];
PixelData pixelDataWrapper = new GrayscalePixelData(
rows,
columns,
bitsAllocated,
bitsStored,
highBit,
isSigned,
pixelData);
int i = 0;
for (int y = 0; y < rows; y++)
{
for (int x = 0; x < columns; x++)
{
pixelDataWrapper.SetPixel(x, y, i);
i++;
}
}
int left = 1, top = 1, right = 3, bottom = 3;
int pixelCount = 0;
pixelDataWrapper.ForEachPixel(left, top, right, bottom,
delegate(int j, int x, int y, int pixelIndex)
{
if (j == 0)
Assert.AreEqual(6, pixelDataWrapper.GetPixel(pixelIndex));
else if (j == 1)
Assert.AreEqual(7, pixelDataWrapper.GetPixel(pixelIndex));
else if (j == 3)
Assert.AreEqual(11, pixelDataWrapper.GetPixel(pixelIndex));
pixelCount++;
});
Assert.AreEqual(9, pixelCount);
}
private static double CalculateStandardDeviation
(
double mean,
RectangleF roiBoundingBox,
GrayscalePixelData pixelData,
IModalityLut modalityLut,
IsPointInRoiDelegate isPointInRoi
)
{
double sum = 0;
int pixelCount = 0;
var boundingBox = RectangleUtilities.RoundInflate(RectangleUtilities.ConvertToPositiveRectangle(roiBoundingBox));
pixelData.ForEachPixel(
boundingBox.Left,
boundingBox.Top,
boundingBox.Right,
boundingBox.Bottom,
delegate(int i, int x, int y, int pixelIndex)
{
if (isPointInRoi(x, y)) {
++pixelCount;
int storedValue = pixelData.GetPixel(pixelIndex);
double realValue = modalityLut != null ? modalityLut[storedValue] : storedValue;
double deviation = realValue - mean;
sum += deviation*deviation;
}
});
if (pixelCount == 0)
return 0;
return Math.Sqrt(sum/pixelCount);
}
