C++ DImage::imresize方法代码示例

void GaussianPyramid::ConstructPyramidLevels(const DImage &image, double ratio, int _nLevels)
{
	// the ratio cannot be arbitrary numbers
	if(ratio>0.98 || ratio<0.4)
		ratio=0.75;
	nLevels = _nLevels;
	if(ImPyramid!=NULL)
		delete []ImPyramid;
	ImPyramid=new DImage[nLevels];
	ImPyramid[0].copyData(image);
	double baseSigma=(1/ratio-1);
	int n=log(0.25)/log(ratio);
	double nSigma=baseSigma*n;
	for(int i=1;i<nLevels;i++)
	{
		DImage foo;
		if(i<=n)
		{
			double sigma=baseSigma*i;
			image.GaussianSmoothing(foo,sigma,sigma*3);
			foo.imresize(ImPyramid[i],pow(ratio,i));
		}
		else
		{
			ImPyramid[i-n].GaussianSmoothing(foo,nSigma,nSigma*3);
			double rate=(double)pow(ratio,i)*image.width()/foo.width();
			foo.imresize(ImPyramid[i],rate);
		}
	}
}

//--------------------------------------------------------------------------------------
// function to perfomr coarse to fine optical flow estimation
//--------------------------------------------------------------------------------------
void OpticalFlow::Coarse2FineFlow(DImage &vx, DImage &vy, DImage &warpI2,const DImage &Im1, const DImage &Im2, double alpha, double ratio, int minWidth, 
																	 int nOuterFPIterations, int nInnerFPIterations, int nCGIterations)
{
    
	// first build the pyramid of the two images
	GaussianPyramid GPyramid1;
	GaussianPyramid GPyramid2;
	if(IsDisplay)
		cout<<"Constructing pyramid...";
	GPyramid1.ConstructPyramid(Im1,ratio,minWidth);
	GPyramid2.ConstructPyramid(Im2,ratio,minWidth);
	if(IsDisplay)
		cout<<"done!"<<endl;
	
	// now iterate from the top level to the bottom
	DImage Image1,Image2,WarpImage2;


	// initialize noise

    // cout << GPyramid1.nlevels()  << " pyramid levels\n";

	for(int k=GPyramid1.nlevels()-1;k>=0;k--)
	{
		if(IsDisplay)
			cout<<"Pyramid level "<<k+1;
		int width=GPyramid1.Image(k).width();
		int height=GPyramid1.Image(k).height();
		im2feature(Image1,GPyramid1.Image(k));
		im2feature(Image2,GPyramid2.Image(k));

        // cout << "\t- level " << k+1 << " size " << width <<"x" << height <<endl;

		if(k==GPyramid1.nlevels()-1) // if at the top level
		{
			vx.allocate(width,height);
			vy.allocate(width,height);
			WarpImage2.copyData(Image2);
		}
		else
		{

			vx.imresize(width,height);
			vx.Multiplywith(1/ratio);
			vy.imresize(width,height);
			vy.Multiplywith(1/ratio);
			if(interpolation == Bilinear)
				warpFL(WarpImage2,Image1,Image2,vx,vy);
			else
				Image2.warpImageBicubicRef(Image1,WarpImage2,vx,vy);
		}
		SmoothFlowSOR(Image1,Image2,WarpImage2,vx,vy,alpha,nOuterFPIterations+k,nInnerFPIterations,nCGIterations+k*3);

		//GMPara.display();
		if(IsDisplay)
			cout<<endl;
	}
	//warpFL(warpI2,Im1,Im2,vx,vy);
	Im2.warpImageBicubicRef(Im1,warpI2,vx,vy);
	warpI2.threshold();
}

//------------------------------------------------------------------------------------------------
// multi-grid belie propagation
//------------------------------------------------------------------------------------------------
void BPFlow::generateCoarserLevel(BPFlow &bp)
{
	//------------------------------------------------------------------------------------------------
	// set the dimensions and parameters
	//------------------------------------------------------------------------------------------------
	bp.Width=Width/2;
	if(Width%2==1)
		bp.Width++;

	bp.Height=Height/2;
	if(Height%2==1)
		bp.Height++;

	bp.Area=bp.Width*bp.Height;
	bp.s=s;
	bp.d=d;

	DImage foo;
	Im_s.smoothing(foo);
	foo.imresize(bp.Im_s,bp.Width,bp.Height);
	Im_d.smoothing(foo);
	foo.imresize(bp.Im_d,bp.Width,bp.Height);

	bp.IsDisplay=IsDisplay;
	bp.nNeighbors=nNeighbors;

	//------------------------------------------------------------------------------------------------
	// allocate buffers
	//------------------------------------------------------------------------------------------------
	for(int i=0;i<2;i++)
	{
		bp.pOffset[i]=new int[bp.Area];
		bp.pWinSize[i]=new int[bp.Area];
		ReduceImage(bp.pOffset[i],Width,Height,pOffset[i]);
		ReduceImage(bp.pWinSize[i],Width,Height,pWinSize[i]);
		for(int j = 0;j<bp.Area;j++)
			bp.pWinSize[i][j] = __max(bp.pWinSize[i][j],1);
	}
	//------------------------------------------------------------------------------------------------
	// generate data term
	//------------------------------------------------------------------------------------------------
	bp.nTotalMatches=bp.AllocateBuffer(bp.pDataTerm,bp.ptrDataTerm,bp.pWinSize[0],bp.pWinSize[1]);
	for(int i=0;i<bp.Height;i++)
		for(int j=0;j<bp.Width;j++)
		{
			int offset=i*bp.Width+j;
			for(int ii=0;ii<2;ii++)
				for(int jj=0;jj<2;jj++)
				{
					int y=i*2+ii;
					int x=j*2+jj;
					if(y<Height && x<Width)
					{
						int nStates=(bp.pWinSize[0][offset]*2+1)*(bp.pWinSize[1][offset]*2+1);
						for(int k=0;k<nStates;k++)
							bp.pDataTerm[offset].data()[k]+=pDataTerm[y*Width+x].data()[k];
					}
				}
		}
	//------------------------------------------------------------------------------------------------
	// generate range term
	//------------------------------------------------------------------------------------------------
	bp.ComputeRangeTerm(gamma/2);
}

//--------------------------------------------------------------------------------------
// function to perfomr coarse to fine optical flow estimation
//--------------------------------------------------------------------------------------
void OpticalFlow::Coarse2FineFlow(DImage &vx, DImage &vy, DImage &warpI2,const DImage &Im1, const DImage &Im2, double alpha, double ratio, int minWidth, 
																	 int nOuterFPIterations, int nInnerFPIterations, int nCGIterations)
{
	// first build the pyramid of the two images
	GaussianPyramid GPyramid1;
	GaussianPyramid GPyramid2;
	if(IsDisplay)
		cout<<"Constructing pyramid...";
	GPyramid1.ConstructPyramid(Im1,ratio,minWidth);
	GPyramid2.ConstructPyramid(Im2,ratio,minWidth);
	if(IsDisplay)
		cout<<"done!"<<endl;
	
	// now iterate from the top level to the bottom
	DImage Image1,Image2,WarpImage2;
	//GaussianMixture GMPara(Im1.nchannels()+2);

	// initialize noise
	switch(noiseModel){
	case GMixture:
		GMPara.reset(Im1.nchannels()+2);
		break;
	case Lap:
		LapPara.allocate(Im1.nchannels()+2);
		for(int i = 0;i<LapPara.dim();i++)
			LapPara[i] = 0.02;
		break;
	}

	for(int k=GPyramid1.nlevels()-1;k>=0;k--)
	{
		if(IsDisplay)
			cout<<"Pyramid level "<<k;
		int width=GPyramid1.Image(k).width();
		int height=GPyramid1.Image(k).height();
		im2feature(Image1,GPyramid1.Image(k));
		im2feature(Image2,GPyramid2.Image(k));

		if(k==GPyramid1.nlevels()-1) // if at the top level
		{
			vx.allocate(width,height);
			vy.allocate(width,height);
			//warpI2.copyData(Image2);
			WarpImage2.copyData(Image2);
		}
		else
		{

			vx.imresize(width,height);
			vx.Multiplywith(1/ratio);
			vy.imresize(width,height);
			vy.Multiplywith(1/ratio);
			//warpFL(warpI2,GPyramid1.Image(k),GPyramid2.Image(k),vx,vy);
			if(interpolation == Bilinear)
				warpFL(WarpImage2,Image1,Image2,vx,vy);
			else
				Image2.warpImageBicubicRef(Image1,WarpImage2,vx,vy);
		}
		//SmoothFlowPDE(GPyramid1.Image(k),GPyramid2.Image(k),warpI2,vx,vy,alpha,nOuterFPIterations,nInnerFPIterations,nCGIterations);
		//SmoothFlowPDE(Image1,Image2,WarpImage2,vx,vy,alpha*pow((1/ratio),k),nOuterFPIterations,nInnerFPIterations,nCGIterations,GMPara);
		
		//SmoothFlowPDE(Image1,Image2,WarpImage2,vx,vy,alpha,nOuterFPIterations,nInnerFPIterations,nCGIterations);
		SmoothFlowSOR(Image1,Image2,WarpImage2,vx,vy,alpha,nOuterFPIterations+k,nInnerFPIterations,nCGIterations+k*3);

		//GMPara.display();
		if(IsDisplay)
			cout<<endl;
	}
	//warpFL(warpI2,Im1,Im2,vx,vy);
	Im2.warpImageBicubicRef(Im1,warpI2,vx,vy);
	warpI2.threshold();
}