public WatershedPixel RemoveAtFront()
{
WatershedPixel temp = queue[0];
queue.RemoveAt(0);
return(temp);
}
private void CreatePixelMapAndHeightSortedArray(Image <Gray, byte> wtImg)
{
MIplImage data = wtImg.MIplImage;
_pictureWidth = data.width;
_pictureHeight = data.height;
// pixel map holds every pixel thus size of (_pictureWidth * _pictureHeight)
_pixelMap = new Dictionary <string, WatershedPixel>(_pictureWidth * _pictureHeight);
unsafe
{
int offset = data.widthStep - data.width;
byte *ptr = (byte *)(data.imageData);
// get histogram of all values in grey = height
for (int y = 0; y < data.height; y++)
{
for (int x = 0; x < data.width; x++, ptr++)
{
WatershedPixel p = new WatershedPixel(x, y, *ptr);
// add every pixel to the pixel map
_pixelMap.Add(p.X.ToString() + "," + p.Y.ToString(), p);
_heightSortedList[*ptr].Add(p);
}
ptr += offset;
}
}
this._currentLabel = 0;
}
public void AddToEnd(WatershedPixel p)
{
queue.Add(p);
}
private List<WatershedPixel> GetNeighbouringPixels(WatershedPixel centerPixel)
{
List<WatershedPixel> temp = new List<WatershedPixel>();
if (_numberOfNeighbours == 8)
{
/*
CP = Center pixel
(X,Y) -- get all 8 connected
|-1,-1|0,-1|1,-1|
|-1, 0| CP |1, 0|
|-1,+1|0,+1|1,+1|
*/
// -1, -1
if ((centerPixel.X - 1) >= 0 && (centerPixel.Y - 1) >= 0)
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + (centerPixel.Y - 1).ToString()]);
// 0, -1
if ((centerPixel.Y - 1) >= 0)
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y - 1).ToString()]);
// 1, -1
if ((centerPixel.X + 1) < _pictureWidth && (centerPixel.Y - 1) >= 0)
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + (centerPixel.Y - 1).ToString()]);
// -1, 0
if ((centerPixel.X - 1) >= 0)
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + centerPixel.Y.ToString()]);
// 1, 0
if ((centerPixel.X + 1) < _pictureWidth)
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + centerPixel.Y.ToString()]);
// -1, 1
if ((centerPixel.X - 1) >= 0 && (centerPixel.Y + 1) < _pictureHeight)
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + (centerPixel.Y + 1).ToString()]);
// 0, 1
if ((centerPixel.Y + 1) < _pictureHeight)
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y + 1).ToString()]);
// 1, 1
if ((centerPixel.X + 1) < _pictureWidth && (centerPixel.Y + 1) < _pictureHeight)
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + (centerPixel.Y + 1).ToString()]);
}
else
{
/*
CP = Center pixel, N/A = not used
(X,Y) -- get only 4 connected
| N/A |0,-1| N/A |
|-1, 0| CP |+1, 0|
| N/A |0,+1| N/A |
*/
// -1, 0
if ((centerPixel.X - 1) >= 0)
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + centerPixel.Y.ToString()]);
// 0, -1
if ((centerPixel.Y - 1) >= 0)
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y - 1).ToString()]);
// 1, 0
if ((centerPixel.X + 1) < _pictureWidth)
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + centerPixel.Y.ToString()]);
// 0, 1
if ((centerPixel.Y + 1) < _pictureHeight)
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y + 1).ToString()]);
}
return temp;
}
private void CreatePixelMapAndHeightSortedArray(Image<Gray, byte> wtImg)
{
MIplImage data = wtImg.MIplImage;
_pictureWidth = data.width;
_pictureHeight = data.height;
// pixel map holds every pixel thus size of (_pictureWidth * _pictureHeight)
_pixelMap = new Dictionary<string, WatershedPixel>(_pictureWidth * _pictureHeight);
unsafe
{
int offset = data.widthStep - data.width;
byte* ptr = (byte*)(data.imageData);
// get histogram of all values in grey = height
for (int y = 0; y < data.height; y++)
{
for (int x = 0; x < data.width; x++, ptr++)
{
WatershedPixel p = new WatershedPixel(x, y, *ptr);
// add every pixel to the pixel map
_pixelMap.Add(p.X.ToString() + "," + p.Y.ToString(), p);
_heightSortedList[*ptr].Add(p);
}
ptr += offset;
}
}
this._currentLabel = 0;
}
public override bool Equals(Object obj)
{
WatershedPixel p = (WatershedPixel)obj;
return(X == p.X && X == p.Y);
}
public void AddToEnd(WatershedPixel p)
{
queue.Add(p);
}
private List <WatershedPixel> GetNeighbouringPixels(WatershedPixel centerPixel)
{
List <WatershedPixel> temp = new List <WatershedPixel>();
if (_numberOfNeighbours == 8)
{
/*
* CP = Center pixel
* (X,Y) -- get all 8 connected
|-1,-1|0,-1|1,-1|
|-1, 0| CP |1, 0|
|-1,+1|0,+1|1,+1|
*/
// -1, -1
if ((centerPixel.X - 1) >= 0 && (centerPixel.Y - 1) >= 0)
{
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + (centerPixel.Y - 1).ToString()]);
}
// 0, -1
if ((centerPixel.Y - 1) >= 0)
{
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y - 1).ToString()]);
}
// 1, -1
if ((centerPixel.X + 1) < _pictureWidth && (centerPixel.Y - 1) >= 0)
{
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + (centerPixel.Y - 1).ToString()]);
}
// -1, 0
if ((centerPixel.X - 1) >= 0)
{
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + centerPixel.Y.ToString()]);
}
// 1, 0
if ((centerPixel.X + 1) < _pictureWidth)
{
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + centerPixel.Y.ToString()]);
}
// -1, 1
if ((centerPixel.X - 1) >= 0 && (centerPixel.Y + 1) < _pictureHeight)
{
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + (centerPixel.Y + 1).ToString()]);
}
// 0, 1
if ((centerPixel.Y + 1) < _pictureHeight)
{
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y + 1).ToString()]);
}
// 1, 1
if ((centerPixel.X + 1) < _pictureWidth && (centerPixel.Y + 1) < _pictureHeight)
{
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + (centerPixel.Y + 1).ToString()]);
}
}
else
{
/*
* CP = Center pixel, N/A = not used
* (X,Y) -- get only 4 connected
| N/A |0,-1| N/A |
|-1, 0| CP |+1, 0|
| N/A |0,+1| N/A |
*/
// -1, 0
if ((centerPixel.X - 1) >= 0)
{
temp.Add(_pixelMap[(centerPixel.X - 1).ToString() + "," + centerPixel.Y.ToString()]);
}
// 0, -1
if ((centerPixel.Y - 1) >= 0)
{
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y - 1).ToString()]);
}
// 1, 0
if ((centerPixel.X + 1) < _pictureWidth)
{
temp.Add(_pixelMap[(centerPixel.X + 1).ToString() + "," + centerPixel.Y.ToString()]);
}
// 0, 1
if ((centerPixel.Y + 1) < _pictureHeight)
{
temp.Add(_pixelMap[centerPixel.X.ToString() + "," + (centerPixel.Y + 1).ToString()]);
}
}
return(temp);
}
private void Segment()
{
// Geodesic SKIZ (skeleton by influence zones) of each level height
for (int h = 0; h < _heightSortedList.Count; h++)
{
// get all pixels for current height
foreach (WatershedPixel heightSortedPixel in _heightSortedList[h])
{
heightSortedPixel.Label = WatershedCommon.MASK;
// for each pixel on current height get neighbouring pixels
List <WatershedPixel> neighbouringPixels = GetNeighbouringPixels(heightSortedPixel);
// initialize queue with neighbours at level h of current basins or watersheds
foreach (WatershedPixel neighbouringPixel in neighbouringPixels)
{
if (neighbouringPixel.Label > 0 || neighbouringPixel.Label == WatershedCommon.WSHED)
{
heightSortedPixel.Distance = 1;
_fifoQueue.AddToEnd(heightSortedPixel);
break;
}
}
}
_currentDistance = 1;
_fifoQueue.AddToEnd(FictitiousPixel);
// extend basins
while (true)
{
WatershedPixel p = _fifoQueue.RemoveAtFront();
if (p.Equals(FictitiousPixel))
{
if (_fifoQueue.IsEmpty)
{
break;
}
else
{
_fifoQueue.AddToEnd(FictitiousPixel);
_currentDistance++;
p = _fifoQueue.RemoveAtFront();
}
}
List <WatershedPixel> neighbouringPixels = GetNeighbouringPixels(p);
// labelling p by inspecting neighbours
foreach (WatershedPixel neighbouringPixel in neighbouringPixels)
{
// neighbouringPixel belongs to an existing basin or to watersheds
// in the original algorithm the condition is:
// if (neighbouringPixel.Distance < currentDistance &&
// (neighbouringPixel.Label > 0 || neighbouringPixel.Label == WatershedCommon.WSHED))
// but this returns incomplete borders so the this one is used
if (neighbouringPixel.Distance <= _currentDistance &&
(neighbouringPixel.Label > 0 || neighbouringPixel.Label == WatershedCommon.WSHED))
{
if (neighbouringPixel.Label > 0)
{
// the commented condition is also in the original algorithm
// but it also gives incomplete borders
if (p.Label == WatershedCommon.MASK /*|| p.Label == WatershedCommon.WSHED*/)
{
p.Label = neighbouringPixel.Label;
}
else if (p.Label != neighbouringPixel.Label)
{
p.Label = WatershedCommon.WSHED;
_watershedPixelCount++;
}
}
else if (p.Label == WatershedCommon.MASK)
{
p.Label = WatershedCommon.WSHED;
_watershedPixelCount++;
}
}
// neighbouringPixel is plateau pixel
else if (neighbouringPixel.Label == WatershedCommon.MASK && neighbouringPixel.Distance == 0)
{
neighbouringPixel.Distance = _currentDistance + 1;
_fifoQueue.AddToEnd(neighbouringPixel);
}
}
}
// detect and process new minima at height level h
foreach (WatershedPixel p in _heightSortedList[h])
{
// reset distance to zero
p.Distance = 0;
// if true then p is inside a new minimum
if (p.Label == WatershedCommon.MASK)
{
// create new label
_currentLabel++;
p.Label = _currentLabel;
_fifoQueue.AddToEnd(p);
while (!_fifoQueue.IsEmpty)
{
WatershedPixel q = _fifoQueue.RemoveAtFront();
// check neighbours of q
List <WatershedPixel> neighbouringPixels = GetNeighbouringPixels(q);
foreach (WatershedPixel neighbouringPixel in neighbouringPixels)
{
if (neighbouringPixel.Label == WatershedCommon.MASK)
{
neighbouringPixel.Label = _currentLabel;
_fifoQueue.AddToEnd(neighbouringPixel);
}
}
}
}
}
}
}
