JAVA圖像縮放處理

1、JAVA圖像縮放處理 今天在網(wǎng)上看到了一篇關(guān)于JAVA圖像處理的文章，博主貼出了一個處理類：特點是高品質(zhì)縮小，具體代碼如下：import java.awt.image.BufferedImage;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import javax.imageio.ImageIO;public class ImageScale     privat

2、e int width;    private int height;    private int scaleWidth;    double support = (double) 3.0;    double contrib;    double normContrib;&#

3、160;   double tmpContrib;    int startContrib, stopContrib;    int nDots;    int nHalfDots;    public BufferedImage imageZoomOut(BufferedImage srcBufferImage, i

4、nt w, int h, boolean lockScale)         width = srcBufferImage.getWidth();        height = srcBufferImage.getHeight();        scal

5、eWidth = w;        if (lockScale)             h = w * height / width;             

6、60;  if (DetermineResultSize(w, h) = 1)             return srcBufferImage;                CalContrib();   

7、;     BufferedImage pbOut = HorizontalFiltering(srcBufferImage, w);        BufferedImage pbFinalOut = VerticalFiltering(pbOut, h);        return pbFin

8、alOut;        /* */*     * 決定圖像尺寸     */    private int DetermineResultSize(int w, int h)         double 

9、scaleH, scaleV;        scaleH = (double) w / (double) width;        scaleV = (double) h / (double) height;        /

10、 需要判斷一下scaleH，scaleV，不做放大操作        if (scaleH >= 1.0 && scaleV >= 1.0)             return 1;       &#

11、160;        return 0;     / end of DetermineResultSize()    private double Lanczos(int i, int inWidth, int outWidth, double Support)   

12、      double x;        x = (double) i * (double) outWidth / (double) inWidth;        return Math.sin(x * Math.PI) / 

13、;(x * Math.PI) * Math.sin(x * Math.PI / Support) / (x * Math.PI / Support);     / end of Lanczos()    /    / Assumption: same horizonta

14、l and vertical scaling factor    /    private void CalContrib()         nHalfDots = (int) (double) width * support / (double) scaleWidth);&#

15、160;       nDots = nHalfDots * 2 + 1;        try             contrib = new doublenDots;    

16、0;       normContrib = new doublenDots;            tmpContrib = new doublenDots;         catch (Exception e)  

17、           System.out.println("init contrib,normContrib,tmpContrib" + e);                int center = nHalfDots;  &

18、#160;     contribcenter = 1.0;        double weight = 0.0;        int i = 0;        for (i = 1; 

19、;i <= center; i+)             contribcenter + i = Lanczos(i, width, scaleWidth, support);            weight += c

20、ontribcenter + i;                for (i = center - 1; i >= 0; i-)             contribi =

21、0;contribcenter * 2 - i;                weight = weight * 2 + 1.0;        for (i = 0; i <= center

22、; i+)             normContribi = contribi / weight;                for (i = center + 1; i <&

23、#160;nDots; i+)             normContribi = normContribcenter * 2 - i;             / end of CalContrib()   

24、; / 處理邊緣    private void CalTempContrib(int start, int stop)         double weight = 0;        int i = 0;    &

25、#160;   for (i = start; i <= stop; i+)             weight += contribi;                for

26、60;(i = start; i <= stop; i+)             tmpContribi = contribi / weight;             / end of CalTem

27、pContrib()    private int GetRedValue(int rgbValue)         int temp = rgbValue & 0x00ff0000;        return temp >> 16;  

28、;      private int GetGreenValue(int rgbValue)         int temp = rgbValue & 0x0000ff00;        return temp >> 8; &

29、#160;      private int GetBlueValue(int rgbValue)         return rgbValue & 0x000000ff;        private int ComRGB(int redValue, int

30、 greenValue, int blueValue)         return (redValue << 16) + (greenValue << 8) + blueValue;        / 行水平濾波    private

31、 int HorizontalFilter(BufferedImage bufImg, int startX, int stopX, int start, int stop, int y,            double pContrib)        

32、 double valueRed = 0.0;        double valueGreen = 0.0;        double valueBlue = 0.0;        int valueRGB = 0;

33、0;       int i, j;        for (i = startX, j = start; i <= stopX; i+, j+)             valueR

34、GB = bufImg.getRGB(i, y);            valueRed += GetRedValue(valueRGB) * pContribj;            valueGreen += GetGreenValue(valueRGB)

35、60;* pContribj;            valueBlue += GetBlueValue(valueRGB) * pContribj;                valueRGB = ComRGB(Clip(int) v

36、alueRed), Clip(int) valueGreen), Clip(int) valueBlue);        return valueRGB;     / end of HorizontalFilter()    / 圖片水平濾波    private BufferedIma

37、ge HorizontalFiltering(BufferedImage bufImage, int iOutW)         int dwInW = bufImage.getWidth();        int dwInH = bufImage.getHeight();    &#

38、160;   int value = 0;        BufferedImage pbOut = new BufferedImage(iOutW, dwInH, BufferedImage.TYPE_INT_RGB);        for (int x = 0; 

39、x < iOutW; x+)             int startX;            int start;            int X 

40、;= (int) (double) x) * (double) dwInW) / (double) iOutW) + 0.5);            int y = 0;            startX 

41、= X - nHalfDots;            if (startX < 0)                 startX = 0;       

42、;         start = nHalfDots - X;             else                 start = 0

43、;                        int stop;            int stopX = X + nHalfDots;   

44、         if (stopX > (dwInW - 1)                 stopX = dwInW - 1;         &

45、#160;      stop = nHalfDots + (dwInW - 1 - X);             else                 

46、stop = nHalfDots * 2;                        if (start > 0 | stop < nDots - 1)     &

47、#160;           CalTempContrib(start, stop);                for (y = 0; y < dwInH; y+)      

48、               value = HorizontalFilter(bufImage, startX, stopX, start, stop, y, tmpContrib);               &#

49、160;    pbOut.setRGB(x, y, value);                             else         

50、0;       for (y = 0; y < dwInH; y+)                     value = HorizontalFilter(bufImage, startX, sto

51、pX, start, stop, y, normContrib);                    pbOut.setRGB(x, y, value);               &

52、#160;                            return pbOut;     / end of HorizontalFiltering()    private

53、60;int VerticalFilter(BufferedImage pbInImage, int startY, int stopY, int start, int stop, int x,            double pContrib)        &#

54、160;double valueRed = 0.0;        double valueGreen = 0.0;        double valueBlue = 0.0;        int valueRGB = 0; 

55、       int i, j;        for (i = startY, j = start; i <= stopY; i+, j+)             valueRGB

56、 = pbInImage.getRGB(x, i);            valueRed += GetRedValue(valueRGB) * pContribj;            valueGreen += GetGreenValue(valueRGB)&#

57、160;* pContribj;            valueBlue += GetBlueValue(valueRGB) * pContribj;                valueRGB = ComRGB(Clip(int) 

58、valueRed), Clip(int) valueGreen), Clip(int) valueBlue);        / System.out.println(valueRGB);        return valueRGB;     / end of VerticalFilter()&#

59、160;   private BufferedImage VerticalFiltering(BufferedImage pbImage, int iOutH)         int iW = pbImage.getWidth();        int iH = pbImage.get

60、Height();        int value = 0;        BufferedImage pbOut = new BufferedImage(iW, iOutH, BufferedImage.TYPE_INT_RGB);        for 

61、(int y = 0; y < iOutH; y+)             int startY;            int start;         &

62、#160;  int Y = (int) (double) y) * (double) iH) / (double) iOutH) + 0.5);            startY = Y - nHalfDots;      &

63、#160;     if (startY < 0)                 startY = 0;                start =&

64、#160;nHalfDots - Y;             else                 start = 0;           &

65、#160;            int stop;            int stopY = Y + nHalfDots;            if (stopY

66、 > (int) (iH - 1)                 stopY = iH - 1;                stop = nHalf

67、Dots + (iH - 1 - Y);             else                 stop = nHalfDots * 2;    &

68、#160;                   if (start > 0 | stop < nDots - 1)                &

69、#160;CalTempContrib(start, stop);                for (int x = 0; x < iW; x+)                

70、     value = VerticalFilter(pbImage, startY, stopY, start, stop, x, tmpContrib);                    pbOut.setRGB(x, y, value)

71、;                             else                 for (int x = 0; x < iW; x+)