五种基于RGB色彩空间统计的皮肤检测算法

原文链接：http://blog.csdn.net/jia20003/article/details/7694408，尊重原创！

申明：文中的方法我还没有进行测试，我只是先留着以后用，我目前正在使用的人脸检测的色彩模型的效果也不错，但是在一些特殊的情况下Cover的不是很好，等有时间把这几种方法都试验一下做一个对比。

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最近一直在研究多脸谱识别以及如何分辨多个皮肤区域是否是人脸的问题

网上找了很多资料，看了很多篇文章，将其中基于RGB色彩空间识别皮肤

的统计算法做了一下总结，统计识别方法主要是简单相比与很多其它基于

机器学习的算法，本人总结了五种RGB色彩空间的统计算法源码如下：

Skin Filter1：

 public class SkinFilter1 extends AbstractBufferedImageOp {

     @Override
     public BufferedImage filter(BufferedImage src, BufferedImage dest) {
         int width = src.getWidth();
         int height = src.getHeight();

         if ( dest == null )
             dest = createCompatibleDestImage( src, null );

         int[] inPixels = new int[width*height];
         int[] outPixels = new int[width*height];
         getRGB( src, 0, 0, width, height, inPixels );
         int index = 0;
         for(int row=0; row<height; row++) {
             int ta = 0, tr = 0, tg = 0, tb = 0;
             for(int col=0; col<width; col++) {
                 index = row * width + col;
                 ta = (inPixels[index] >> 24) & 0xff;
                 tr = (inPixels[index] >> 16) & 0xff;
                 tg = (inPixels[index] >> 8) & 0xff;
                 tb = inPixels[index] & 0xff;

                 // detect skin method...
                 double sum = tr + tg + tb;
                 if (((double)tr/(double)tb > 1.185) &&
                     ((double)(tr*tb)/(double)(sum*sum)>0.107) &&
                     ((double)(tr*tg)/(double)(sum*sum)>0.112))
                 {
                     tr = tg = tb = 0; // black - skin detected!!
                 } else {
                     tr = tg = tb = 255; // white color means non-skin pixel
                 }
                 outPixels[index] = (ta << 24) | (tr << 16) | (tg << 8) | tb;
             }
         }
         setRGB( dest, 0, 0, width, height, outPixels );
         return dest;
     }
 }

Skin Filter2：

 public class SkinFilter2 extends AbstractBufferedImageOp {

     @Override
     public BufferedImage filter(BufferedImage src, BufferedImage dest) {
         int width = src.getWidth();
         int height = src.getHeight();

         if ( dest == null )
             dest = createCompatibleDestImage( src, null );

         int[] inPixels = new int[width*height];
         int[] outPixels = new int[width*height];
         getRGB( src, 0, 0, width, height, inPixels );
         int index = 0;
         for(int row=0; row<height; row++) {
             int ta = 0, tr = 0, tg = 0, tb = 0;
             for(int col=0; col<width; col++) {
                 index = row * width + col;
                 ta = (inPixels[index] >> 24) & 0xff;
                 tr = (inPixels[index] >> 16) & 0xff;
                 tg = (inPixels[index] >> 8) & 0xff;
                 tb = inPixels[index] & 0xff;
                 double sum = tr + tg + tb;


                 if(((double)3*tb*tr*tr/(double)(sum*sum*sum)>0.1276)&&
                     ((double)(tr*tb+tg*tg)/(double)(tg*tb)>2.14)&&
                     ((double)(sum)/(double)(3*tr)+(double)(tr-tg)/(double)(sum)<2.7775))
                 {
                     tr = tg = tb = 0;
                 } else {
                     tr = tg = tb = 255;
                 }
                 outPixels[index] = (ta << 24) | (tr << 16) | (tg << 8) | tb;
             }
         }
         setRGB( dest, 0, 0, width, height, outPixels );
         return dest;
     }
 }

Skin Filter3：

 public class SkinFilter3 extends AbstractBufferedImageOp {

     @Override
     public BufferedImage filter(BufferedImage src, BufferedImage dest) {
         int width = src.getWidth();
         int height = src.getHeight();

         if ( dest == null )
             dest = createCompatibleDestImage( src, null );

         int[] inPixels = new int[width*height];
         int[] outPixels = new int[width*height];
         getRGB( src, 0, 0, width, height, inPixels );
         int index = 0;
         for(int row=0; row<height; row++) {
             int ta = 0, tr = 0, tg = 0, tb = 0;
             for(int col=0; col<width; col++) {
                 index = row * width + col;
                 ta = (inPixels[index] >> 24) & 0xff;
                 tr = (inPixels[index] >> 16) & 0xff;
                 tg = (inPixels[index] >> 8) & 0xff;
                 tb = inPixels[index] & 0xff;

                 // detect skin method...
                 double sum = tr + tg + tb;
                 if (((double)tg / (double)tg - (double)tr / (double)tb <= -0.0905) &&
                     ((double)(sum) / (double)(3 * tr) + (double)(tr - tg) / (double)(sum) <= 0.9498))
                 {
                     tr = tg = tb = 0;
                 } else {
                     tr = tg = tb = 255;
                 }
                 outPixels[index] = (ta << 24) | (tr << 16) | (tg << 8) | tb;
             }
         }
         setRGB( dest, 0, 0, width, height, outPixels );
         return dest;
     }
 }

Skin Filter4：

 import java.awt.image.BufferedImage;
 /**
  * this skin detection is absolutely good skin classification,
  * i love this one very much
  *
  * this one should be always primary skin detection
  * from all five filters
  *
  * @author zhigang
  *
  */
 public class SkinFilter4 extends AbstractBufferedImageOp {

     @Override
     public BufferedImage filter(BufferedImage src, BufferedImage dest) {
         int width = src.getWidth();
         int height = src.getHeight();

         if ( dest == null )
             dest = createCompatibleDestImage( src, null );

         int[] inPixels = new int[width*height];
         int[] outPixels = new int[width*height];
         getRGB( src, 0, 0, width, height, inPixels );
         int index = 0;
         for(int row=0; row<height; row++) {
             int ta = 0, tr = 0, tg = 0, tb = 0;
             for(int col=0; col<width; col++) {
                 index = row * width + col;
                 ta = (inPixels[index] >> 24) & 0xff;
                 tr = (inPixels[index] >> 16) & 0xff;
                 tg = (inPixels[index] >> 8) & 0xff;
                 tb = inPixels[index] & 0xff;

                 // detect skin method...
                 double sum = tr + tg + tb;
                 if (((double)tb/(double)tg<1.249) &&
                     ((double)sum/(double)(3*tr)>0.696) &&
                     (0.3333-(double)tb/(double)sum>0.014) &&
                     ((double)tg/(double)(3*sum)<0.108))
                 {
                     tr = tg = tb = 0;
                 } else {
                     tr = tg = tb = 255;
                 }
                 outPixels[index] = (ta << 24) | (tr << 16) | (tg << 8) | tb;
             }
         }
         setRGB(dest, 0, 0, width, height, outPixels);
         return dest;
     }
 }

Skin Filter5：

 import java.awt.image.BufferedImage;
 /**
  * this is very good skin detection
  * get real skin segmentation correctly....
  * ohh... cool
  *
  * @author zhigang
  *
  */
 public class SkinFilter5 extends AbstractBufferedImageOp {

     @Override
     public BufferedImage filter(BufferedImage src, BufferedImage dest) {
         int width = src.getWidth();
         int height = src.getHeight();

         if ( dest == null )
             dest = createCompatibleDestImage( src, null );

         int[] inPixels = new int[width*height];
         int[] outPixels = new int[width*height];
         getRGB( src, 0, 0, width, height, inPixels );
         int index = 0;
         for(int row=0; row<height; row++) {
             int ta = 0, tr = 0, tg = 0, tb = 0;
             for(int col=0; col<width; col++) {
                 index = row * width + col;
                 ta = (inPixels[index] >> 24) & 0xff;
                 tr = (inPixels[index] >> 16) & 0xff;
                 tg = (inPixels[index] >> 8) & 0xff;
                 tb = inPixels[index] & 0xff;

                 // detect skin method...
                 double sum = tr + tg + tb;
                 if (((double)tg/(double)tb - (double)tr/(double)tg<=-0.0905)&&
                 ((double)(tg*sum)/(double)(tb*(tr-tg))>3.4857)&&
                 ((double)(sum*sum*sum)/(double)(3*tg*tr*tr)<=7.397)&&
                 ((double)sum/(double)(9*tr)-0.333 > -0.0976))
                 {
                     tr = tg = tb = 0;
                 } else {
                     tr = tg = tb = 255;
                 }
                 outPixels[index] = (ta << 24) | (tr << 16) | (tg << 8) | tb;
             }
         }
         setRGB( dest, 0, 0, width, height, outPixels );
         return dest;
     }