blobdetection.java

自已用MATLAB写的一个blob Detection

package blobDetection;

import java.lang.reflect.*;

//==================================================
//class BlobDetection
//==================================================
public class BlobDetection extends EdgeDetection
{
	// Temp
	Object	parent;
	Method 	filterBlobMethod;
	// Temp
	
	public static int        	blobMaxNumber = 1000;
	public int        			blobNumber;
	public Blob[]     			blob;
	public boolean[]  			gridVisited;

	public int					blobWidthMin, blobHeightMin;
	
//	--------------------------------------------
// Constructor
//	--------------------------------------------
public BlobDetection(int imgWidth, int imgHeight)
{
  super(imgWidth, imgHeight);
  
  gridVisited   = new boolean[nbGridValue];
  blob         	= new Blob[blobMaxNumber];
  blobNumber   	= 0;
  for (int i=0 ; i<blobMaxNumber;i++) 
  		blob[i] = new Blob(this); 

  blobWidthMin	= 0;
  blobHeightMin	= 0;
  
  filterBlobMethod = null;
}

//--------------------------------------------
// setBlobDimensionMin()
//--------------------------------------------
/*
public void setBlobDimensionMin(int w, int h)
{
  if (w<0) w=0;
  if (h<0) h=0;
  if (w>imgWidth) w=imgWidth;
  if (h>imgHeight) h=imgHeight;
  
  blobWidthMin	= w;
  blobHeightMin	= h;
}
*/
//--------------------------------------------
// setNumberBlobMax()
//--------------------------------------------
public void setBlobMaxNumber(int nb)
{
	blobMaxNumber = nb;
}

//--------------------------------------------
// getBlob()
//--------------------------------------------
public Blob getBlob(int n)
{
	Blob b=null;
	if (n<blobNumber)
		return blob[n];
	return b;
}

//--------------------------------------------
// getBlobNb()
//--------------------------------------------
public int getBlobNb()
{
	return blobNumber;
}

//--------------------------------------------
// computeBlobs()
//--------------------------------------------
public void computeBlobs(int[] pixels)
{
	// Image
	setImage(pixels);
	
     // Clear gridVisited
     for (int i=0 ; i<nbGridValue; i++) 
     	gridVisited[i]=false;
	
     // Compute Isovalue
	computeIsovalue();
	
     // Get Lines indices
	int		x,y,squareIndex,n;
	int		iEdge;
	int		offx, offy, offAB;
	int		toCompute;
	int		offset;
	float	t;
	float	vx,vy;

	nbLineToDraw 	= 0;
	vx	     		= 0.0f;
    blobNumber   	= 0;
	for (x=0 ; x<resx-1 ; x++)
	{
		vy = 0.0f;
		for (y=0 ; y<resy-1 ; y++)
		{
			 // > offset in the grid
			offset		= x + resx*y;

	         // > if we were already there, just go the next square!
            if (gridVisited[offset] == true) continue;
                     
             // > squareIndex
			squareIndex     = getSquareIndex(x,y);

             // >Found something
			 if (squareIndex > 0 && squareIndex < 15)
			 {
			 	if (blobNumber < blobMaxNumber)
			 	{
					   findBlob(blobNumber,x,y);
						 blobNumber++;
			 		
			 	}
			 }
			vy += stepy;
		}	// for y
		vx += stepx;
	}	// for x
	nbLineToDraw /= 2;
	//blobNumber+=1;
}

//--------------------------------------------
// findBlob()
//--------------------------------------------
public void findBlob(int iBlob, int x, int y)
{
	 // Reset Blob values

	blob[iBlob].id     = iBlob; 
	 blob[iBlob].xMin   =  1000.0f;
	 blob[iBlob].xMax   =  -1000.0f;
	 blob[iBlob].yMin   =  1000.0f;
	 blob[iBlob].yMax   =  -1000.0f;
	 blob[iBlob].nbLine = 0; 

	
	 // Find it !!    
	computeEdgeVertex(iBlob, x,y);
	{
	
	 // > This is just a temp patch (somtimes 'big' blobs are detected on the grid edges)

	 if (blob[iBlob].xMin>=1000.0f || blob[iBlob].xMax<=-1000.0f || blob[iBlob].yMin>=1000.0f || blob[iBlob].yMax<=-1000.0f)
	   blobNumber--;    
	 else  
	 {
		blob[iBlob].update();
        // User Filter
		if (filterBlobMethod != null)
        {
        	try 
			{
        		Boolean returnObj = (Boolean)(filterBlobMethod.invoke(parent, new Object[]{ blob[iBlob] } ));
        		boolean returnValue = returnObj.booleanValue();
        		if (returnValue == false) blobNumber--;    
			} 
        	catch (Exception e) 
			{
				System.out.println("Disabling filterBlobMethod() because of an error.");
				filterBlobMethod = null;
			}
        }
	  }

	}


}

//--------------------------------------------
// computeEdgeVertex()
//--------------------------------------------
void computeEdgeVertex(int iBlob, int x, int y)
{
	 // offset
	 int offset = x+resx*y;
	 
	 // Mark voxel as visited
	 if (gridVisited[offset] == true) return;
	 gridVisited[offset]=true;    
	
	 // 
	 int   iEdge, offx, offy, offAB;
	 int[] edgeOffsetInfo;
	 int   squareIndex     = getSquareIndex(x,y);
	 float vx = (float)x*stepx;
	 float vy = (float)y*stepy;
	 
	 int   n = 0;
	 while ( (iEdge = MetaballsTable.edgeCut[squareIndex][n++]) != -1)
	 {
		edgeOffsetInfo  = MetaballsTable.edgeOffsetInfo[iEdge];
		offx			= edgeOffsetInfo[0];
		offy			= edgeOffsetInfo[1];
		offAB			= edgeOffsetInfo[2];
	
	    if (blob[iBlob].nbLine < Blob.MAX_NBLINE) 
	    	lineToDraw[nbLineToDraw++] = blob[iBlob].line[blob[iBlob].nbLine++] = voxel[(x+offx) + resx*(y+offy)] + offAB;
	    else
	    	return;
	 }
	 
	 int   toCompute = MetaballsTable.edgeToCompute[squareIndex];
	 float t = 0.0f;
	 float value = 0.0f;
	 if (toCompute>0)
	 {
	   if ( (toCompute & 1) > 0) // Edge 0
	   {
	   		t	= (isovalue - gridValue[offset]) / (gridValue[offset+1] - gridValue[offset]); 
			value   = vx*(1.0f-t) + t*(vx+stepx); 
			edgeVrt[voxel[offset]].x = value;
	     
			if (value < blob[iBlob].xMin ) blob[iBlob].xMin = value;
			if (value > blob[iBlob].xMax ) blob[iBlob].xMax = value;
	      
	   }
	   if ( (toCompute & 2) > 0) // Edge 3
	   {
	   		t	= (isovalue - gridValue[offset]) / (gridValue[offset+resx] - gridValue[offset]); 
	   		value   = vy*(1.0f-t) + t*(vy+stepy);
	   		edgeVrt[voxel[offset]+1].y = value;
	     
	   		if (value < blob[iBlob].yMin ) blob[iBlob].yMin = value;
	   		if (value > blob[iBlob].yMax ) blob[iBlob].yMax = value;
	
	   }
				
	 } // toCompute
	
	 // Propagate to neightbors : use of Metaballs.neighborsTable 
	 byte neighborVoxel = MetaballsTable.neightborVoxel[squareIndex];    
	 if (x<resx-2   && (neighborVoxel & (1<<0))>0)        computeEdgeVertex(iBlob, x+1,y);
	 if (x>0        && (neighborVoxel & (1<<1))>0)        computeEdgeVertex(iBlob, x-1,y);
	 if (y<resy-2   && (neighborVoxel & (1<<2))>0)        computeEdgeVertex(iBlob, x,y+1);
	 if (y>0        && (neighborVoxel & (1<<3))>0)        computeEdgeVertex(iBlob, x,y-1);
 
}

//--------------------------------------------
// filterBlob()
//--------------------------------------------
/*
public boolean acceptBlob(Blob b)
{
	if ( (b.w*imgWidth>=blobWidthMin) || (b.h*imgHeight>=blobHeightMin) )
		return true;
	return false;
}
*/
//--------------------------------------------
// activeCustomFilter
//--------------------------------------------
public void activeCustomFilter(Object parent)
{
	this.parent = parent;
	  try 
	  {
	  	filterBlobMethod = parent.getClass().getMethod("newBlobDetectedEvent", new Class[] { Blob.class });
      	//System.out.println("newBlobDetectedEvent found!");
      } catch (Exception e) 
	  {
      	//System.out.println("no such metho or error");
        // no such method, or an error.. which is fine, just ignore
      }
}

};