/// <summary>
/// Calculate value for position in result matrix (made from multiplication of image and kernel)
/// </summary>
/// <param name="image">image</param>
/// <param name="row">current result matrix row</param>
/// <param name="column">current result matrix column</param>
/// <param name="kernel">kernel</param>
/// <param name="kernelSum">Optional. Sum of kernel matrix. If not specified every time it will calculate (bad for performance i guess)</param>
/// <returns>calculated value for specified position</returns>
private IMatrixData CalculateValueForPosition(int row, int column, IMatrix image, IMatrix kernel,
float kernelSum = -1)
{
IMatrixData endValue = ZeroRepresentationOfMatrixData;
for (var i = 0; i < kernel.Height; i++)
{
IMatrixData innerCycleCalculationResult = ZeroRepresentationOfMatrixData;
for (var j = 0; j < kernel.Width; j++)
{
var imageColumn = column + j - 1;
var imageRow = row + i - 1;
//allows bluring edges of the picture (a.k.a prevents from throwing exceptions when kernel is on the edge of the picture)
if (imageColumn < 0 || imageRow < 0 || imageColumn >= image.Width || imageRow >= image.Height)
{
continue;
}
var imageValue = image.GetValue(imageColumn, imageRow);
var kernelValue = kernel.GetValue(j, i);
var imageValueMultipliedByKernelValue = this.arithmeticsController.Multiply(imageValue, kernelValue);
innerCycleCalculationResult = this.arithmeticsController.Add(innerCycleCalculationResult, imageValueMultipliedByKernelValue);
}
endValue = this.arithmeticsController.Add(endValue, innerCycleCalculationResult);
}
if (Math.Abs(kernelSum - (-1)) > 0.001f)
{
if (Math.Abs(kernelSum) < 0.001f)
{
return(endValue.CompareTo(endValue.ZeroRepresentation) < 0 ? endValue.ZeroRepresentation : endValue);
}
return(this.arithmeticsController.Divide(endValue, new FloatNumberMatrixData(kernelSum)));
}
var sum = kernel.Sum;
var sumValue = Convert.ToDouble(sum.RawValue);
if (Math.Abs(sumValue) > 0.001f)
{
return(this.arithmeticsController.Divide(endValue, new FloatNumberMatrixData((float)sumValue)));
}
return(endValue.CompareTo(endValue.ZeroRepresentation) < 0 ? endValue.ZeroRepresentation : endValue);
}
