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@pknam
Last active August 29, 2015 14:25
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using System.Collections;
using System.Collections.Generic;
using OpenCvSharp;
using System.Runtime.InteropServices;
using System;
public class MyBlobLabeling : System.Object
{
public int m_nBlobs;
public List<CvRect> m_recBlobs;
private int m_nWidth;
private int m_nHeight;
// buffer for labeling
private byte[] m_cdataBuf;
private const int MAX_BLOBS = 254;
public MyBlobLabeling()
{
m_nBlobs = MAX_BLOBS;
m_recBlobs = null;
}
public void Label(IplImage image)
{
m_recBlobs = new List<CvRect>();
m_nBlobs = 0;
m_nWidth = image.Width;
m_nHeight = image.Height;
m_cdataBuf = new byte[m_nWidth * m_nHeight];
// copy pixel data
Marshal.Copy(image.ImageData, m_cdataBuf, 0, m_nWidth * m_nHeight);
m_nBlobs = _Labeling();
}
private int _Labeling()
{
int nX, nY;
byte nLabel = 0;
// search blobs
for (nY = 0; nY < m_nHeight; nY++)
{
for (nX = 0; nX < m_nWidth; nX++)
{
// found new blob
if (m_cdataBuf[nY * m_nWidth + nX] == 255)
{
CvRect rt = FindNeighbor(nX, nY, nLabel);
// ignore under 50
if (rt.Width * rt.Height > 50)
{
m_recBlobs.Add(rt);
nLabel++;
}
if (nLabel == MAX_BLOBS)
return m_recBlobs.Count;
}
}
}
return m_recBlobs.Count;
}
// Blob Labeling using BFS
private CvRect FindNeighbor(int nX, int nY, byte nLabel)
{
Queue<CvPoint> q = new Queue<CvPoint>();
int left = nX;
int right = nX;
int top = nY;
int bottom = nY;
q.Enqueue(new CvPoint(nX, nY));
while(q.Count > 0)
{
CvPoint ptTmp = q.Dequeue();
// if already visited
if (m_cdataBuf[ptTmp.Y * m_nWidth + ptTmp.X] == nLabel)
continue;
// check visited
m_cdataBuf[ptTmp.Y * m_nWidth + ptTmp.X] = nLabel;
if (ptTmp.X > 0 && m_cdataBuf[ptTmp.Y * m_nWidth + (ptTmp.X - 1)] == 255)
q.Enqueue(new CvPoint(ptTmp.X - 1, ptTmp.Y));
if (ptTmp.Y > 0 && m_cdataBuf[(ptTmp.Y - 1) * m_nWidth + ptTmp.X] == 255)
q.Enqueue(new CvPoint(ptTmp.X, ptTmp.Y - 1));
if (ptTmp.X < m_nWidth - 1 && m_cdataBuf[ptTmp.Y * m_nWidth + (ptTmp.X + 1)] == 255)
q.Enqueue(new CvPoint(ptTmp.X + 1, ptTmp.Y));
if (ptTmp.Y < m_nHeight - 1 && m_cdataBuf[(ptTmp.Y + 1) * m_nWidth + ptTmp.X] == 255)
q.Enqueue(new CvPoint(ptTmp.X, ptTmp.Y + 1));
if (ptTmp.X < left)
left = ptTmp.X;
if (ptTmp.X > right)
right = ptTmp.X;
if (ptTmp.Y < top)
top = ptTmp.Y;
if (ptTmp.Y > bottom)
bottom = ptTmp.Y;
}
return new CvRect(left, top, right - left, bottom - top);
}
}
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