JAVA图像缩放处理.doc

JAVA图像缩放处理 今天在网上看到了一篇关于JAVA图像处理的文章，博主贴出了一个处理类：特点是高品质缩小，具体代码如下：importjava.awt.image.BufferedImage;importjava.io.File;importjava.io.FileOutputStream;importjava.io.IOException;importjavax.imageio.ImageIO;publicclassImageScaleprivateintwidth;privateintheight;privateintscaleWidth;doublesupport=(double)3.0;doublecontrib;doublenormContrib;doubletmpContrib;intstartContrib,stopContrib;intnDots;intnHalfDots;publicBufferedImageimageZoomOut(BufferedImagesrcBufferImage,intw,inth,booleanlockScale)width=srcBufferImage.getWidth();height=srcBufferImage.getHeight();scaleWidth=w;if(lockScale)h=w*height/width;if(DetermineResultSize(w,h)=1)returnsrcBufferImage;CalContrib();BufferedImagepbOut=HorizontalFiltering(srcBufferImage,w);BufferedImagepbFinalOut=VerticalFiltering(pbOut,h);returnpbFinalOut;/*/*决定图像尺寸*/privateintDetermineResultSize(intw,inth)doublescaleH,scaleV;scaleH=(double)w/(double)width;scaleV=(double)h/(double)height;/需要判断一下scaleH，scaleV，不做放大操作if(scaleH=1.0&scaleV=1.0)return1;return0;/endofDetermineResultSize()privatedoubleLanczos(inti,intinWidth,intoutWidth,doubleSupport)doublex;x=(double)i*(double)outWidth/(double)inWidth;returnMath.sin(x*Math.PI)/(x*Math.PI)*Math.sin(x*Math.PI/Support)/(x*Math.PI/Support);/endofLanczos()/Assumption:samehorizontalandverticalscalingfactor/privatevoidCalContrib()nHalfDots=(int)(double)width*support/(double)scaleWidth);nDots=nHalfDots*2+1;trycontrib=newdoublenDots;normContrib=newdoublenDots;tmpContrib=newdoublenDots;catch(Exceptione)System.out.println(initcontrib,normContrib,tmpContrib+e);intcenter=nHalfDots;contribcenter=1.0;doubleweight=0.0;inti=0;for(i=1;i=0;i-)contribi=contribcenter*2-i;weight=weight*2+1.0;for(i=0;i=center;i+)normContribi=contribi/weight;for(i=center+1;inDots;i+)normContribi=normContribcenter*2-i;/endofCalContrib()/处理边缘privatevoidCalTempContrib(intstart,intstop)doubleweight=0;inti=0;for(i=start;i=stop;i+)weight+=contribi;for(i=start;i16;privateintGetGreenValue(intrgbValue)inttemp=rgbValue&0x0000ff00;returntemp8;privateintGetBlueValue(intrgbValue)returnrgbValue&0x000000ff;privateintComRGB(intredValue,intgreenValue,intblueValue)return(redValue16)+(greenValue8)+blueValue;/行水平滤波privateintHorizontalFilter(BufferedImagebufImg,intstartX,intstopX,intstart,intstop,inty,doublepContrib)doublevalueRed=0.0;doublevalueGreen=0.0;doublevalueBlue=0.0;intvalueRGB=0;inti,j;for(i=startX,j=start;i=stopX;i+,j+)valueRGB=bufImg.getRGB(i,y);valueRed+=GetRedValue(valueRGB)*pContribj;valueGreen+=GetGreenValue(valueRGB)*pContribj;valueBlue+=GetBlueValue(valueRGB)*pContribj;valueRGB=ComRGB(Clip(int)valueRed),Clip(int)valueGreen),Clip(int)valueBlue);returnvalueRGB;/endofHorizontalFilter()/图片水平滤波privateBufferedImageHorizontalFiltering(BufferedImagebufImage,intiOutW)intdwInW=bufImage.getWidth();intdwInH=bufImage.getHeight();intvalue=0;BufferedImagepbOut=newBufferedImage(iOutW,dwInH,BufferedImage.TYPE_INT_RGB);for(intx=0;xiOutW;x+)intstartX;intstart;intX=(int)(double)x)*(double)dwInW)/(double)iOutW)+0.5);inty=0;startX=X-nHalfDots;if(startX(dwInW-1)stopX=dwInW-1;stop=nHalfDots+(dwInW-1-X);elsestop=nHalfDots*2;if(start0|stopnDots-1)CalTempContrib(start,stop);for(y=0;ydwInH;y+)value=HorizontalFilter(bufImage,startX,stopX,start,stop,y,tmpContrib);pbOut.setRGB(x,y,value);elsefor(y=0;ydwInH;y+)value=HorizontalFilter(bufImage,startX,stopX,start,stop,y,normContrib);pbOut.setRGB(x,y,value);returnpbOut;/endofHorizontalFiltering()privateintVerticalFilter(BufferedImagepbInImage,intstartY,intstopY,intstart,intstop,intx,doublepContrib)doublevalueRed=0.0;doublevalueGreen=0.0;doublevalueBlue=0.0;intvalueRGB=0;inti,j;for(i=startY,j=start;i=stopY;i+,j+)valueRGB=pbInImage.getRGB(x,i);valueRed+=GetRedValue(valueRGB)*pContribj;valueGreen+=GetGreenValue(valueRGB)*pContribj;valueBlue+=GetBlueValue(valueRGB)*pContribj;valueRGB=ComRGB(Clip(int)valueRed),Clip(int)valueGreen),Clip(int)valueBlue);/System.out.println(valueRGB);returnvalueRGB;/endofVerticalFilter()privateBufferedImageVerticalFiltering(BufferedImagepbImage,intiOutH)intiW=pbImage.getWidth();intiH=pbImage.getHeight();intvalue=0;BufferedImagepbOut=newBufferedImage(iW,iOutH,BufferedImage.TYPE_INT_RGB);for(inty=0;yiOutH;y+)intstartY;intstart;intY=(int)(double)y)*(double)iH)/(double)iOutH)+0.5);startY=Y-nHalfDots;if(startY(int)(iH-1)stopY=iH-1;stop=nHalfDots+(iH-1-Y);elsestop=nHalfDots*2;if(start0|stopnDots-1)CalTempContrib(start,stop);for(intx=0;xiW;x+)value=VerticalFilter(pbImage,startY,stopY,start,stop,x,tmpContrib);pbOut.setRGB(x,y,value);elsefor(intx=0;xiW;x+)value=VerticalFilter(pbImage,startY,stopY,start,stop,x,normContrib);pbOut.setRGB(x,y,value);returnpbOut;/endofVerticalFiltering()intClip(intx)if(x255)return255;returnx;publicstaticvoidmain(Stringargs)throwsIOExceptionImageScaleis=newImageScale();Stringpath=D:MyDocumentsMyPicturespictrue;BufferedImageimage1=ImageIO.read(newFile(path+test.jpg);intw=200,h=400;BufferedImageimage2=is.imageZoomOut(image1,w