/// <summary>
/// FindVerticalMinimumValues method finds the minimum values of the DP table vertically
/// </summary>
/// <param name="seamTable"></param>
/// <param name="pixels"></param>
private void FindVerticalMinimumValues(ref SeamItem[][] seamTable, Pixel[][] pixels)
{
int width = pixels[0].Length;
int height = pixels.Length;
double min;
int index;
double left, top, right;
for (int i = 1; i < height; i++)
{
for (int j = 0; j < width; j++)
{
left = (Utility.ValidateCoordinate(j - 1, i - 1, width, height)) ?
pixels[i][j].Energy + seamTable[i - 1][j - 1].Value : double.MaxValue;
top = (Utility.ValidateCoordinate(j, i - 1, width, height)) ?
pixels[i][j].Energy + seamTable[i - 1][j].Value : double.MaxValue;
right = (Utility.ValidateCoordinate(j + 1, i - 1, width, height)) ?
pixels[i][j].Energy + seamTable[i - 1][j + 1].Value : double.MaxValue;
(min, index) = FindMinimumIndex(new double[] { left, top, right });
seamTable[i][j] = new SeamItem()
{
Value = min,
ParentIndex = j + index - 1
};
}
}
}
/// <summary>
/// FindHorizontalMinimumValues method finds the minimum values of the DP table horizontally
/// </summary>
/// <param name="seamTable"></param>
/// <param name="pixels"></param>
private void FindHorizontalMinimumValues(ref SeamItem[][] seamTable, Pixel[][] pixels)
{
int width = pixels[0].Length;
int height = pixels.Length;
double min;
int index;
double top, left, bottom;
for (int j = 1; j < width; j++)
{
for (int i = 0; i < height; i++)
{
top = (Utility.ValidateCoordinate(j - 1, i - 1, width, height)) ?
pixels[i][j].Energy + seamTable[i - 1][j - 1].Value : double.MaxValue;
left = (Utility.ValidateCoordinate(j - 1, i, width, height)) ?
pixels[i][j].Energy + seamTable[i][j - 1].Value : double.MaxValue;
bottom = (Utility.ValidateCoordinate(j - 1, i + 1, width, height)) ?
pixels[i][j].Energy + seamTable[i + 1][j - 1].Value : double.MaxValue;
(min, index) = FindMinimumIndex(new double[] { top, left, bottom });
seamTable[i][j] = new SeamItem()
{
Value = min,
ParentIndex = i + index - 1
};
}
}
}
/// <summary>
/// FindHorizontalSeam method for finding the horizontal seams of the image
/// </summary>
/// <param name="carvedPixels"></param>
public void FindHorizontalSeam(ref Pixel[][] carvedPixels)
{
int width = carvedPixels[0].Length;
int height = carvedPixels.Length;
SeamItem[][] seamTable = Utility.Initialize2DArray <SeamItem>(width, height);
for (int i = 0; i < height; i++)
{
seamTable[i][0] = new SeamItem()
{
Value = carvedPixels[i][0].Energy,
ParentIndex = -1,
};
}
FindHorizontalMinimumValues(ref seamTable, carvedPixels);
SeamItem[] lastColumn = new SeamItem[height];
for (int i = 0; i < height; i++)
{
lastColumn[i] = seamTable[i][width - 1];
}
(double min, int index) = FindMinimumIndex(lastColumn);
CarveHorizontalSeam(carvedPixels, seamTable, index, width);
}
/// <summary>
/// FindVerticalSeam method for finding the vertical seams of the image
/// </summary>
/// <param name="carvedPixels"></param>
public void FindVerticalSeam(ref Pixel[][] carvedPixels)
{
int width = carvedPixels[0].Length;
int height = carvedPixels.Length;
SeamItem[][] seamTable = Utility.Initialize2DArray <SeamItem>(width, height);
for (int i = 0; i < width; i++)
{
seamTable[0][i] = new SeamItem()
{
Value = carvedPixels[0][i].Energy,
ParentIndex = -1,
};
}
FindVerticalMinimumValues(ref seamTable, carvedPixels);
(double min, int index) = FindMinimumIndex(seamTable[height - 1]);
CarveVerticalSeam(carvedPixels, seamTable, index, height);
}
