java实现图像转码为字符画的方法

public class ImageProcesser {    private static final char[] charset1 = {'M','8','V','|',':','.',' '}; //默认字符素材集  private char[] charset; //字符画素材集  private String imgString = ""; //储存转化后的字符串      //使用指定字符集构造  public ImageProcesser(char[] charset){   this.charset = charset;  }  //使用默认字符集构造  public ImageProcesser(){   this.charset = charset1;  }    public String getImgString(){   return imgString;  }   /*将图形文件转化为字符画字符串*/  public ImageProcesser toBitmapConvert(String imagepath){   return toBitmapConvert(new File(imagepath));  }  public ImageProcesser toBitmapConvert(File imageFile){      StringBuffer sb = new StringBuffer();   if(!imageFile.exists()){ //当读取的文件不存在时，结束程序    System.out.println("File is not exists!");    System.exit(1);   }   Color color;   try{    BufferedImage buff = ImageIO.read(imageFile); //将图片文件装载如BufferedImage流    buff = compressImage(buff);      int bitmapH = buff.getHeight();    int bitmapW = buff.getWidth();        //逐行扫描图像的像素点，读取RGB值，取其平均值，并从charset中获取相应的字符素材，并装载到sb中    for(int y=0; y<bitmapH; y++){        for(int x=0; x<bitmapW; x++){      int rgb = buff.getRGB(x,y);      color = new Color(rgb);            int cvalue = (color.getRed()+color.getGreen()+color.getBlue()) / 3;      sb.append(charset[(int)((cvalue * charset.length - 1)/255)]+" ");     }     sb.append("/r/n");    }   }catch(IOException ex){    ex.printStackTrace();   }   imgString = sb.toString();   return this;  }      /*图像文件预处理:将图片压缩到 最长边为 100px*/  private BufferedImage compressImage(BufferedImage srcImg){   int h = srcImg.getHeight();   int w = srcImg.getWidth();   if(Math.max(h,w)<=100)    return srcImg;   int new_H;   int new_W;   if(w>h){    new_W = 100;    new_H = 100*h/w ;   }else{    new_H = 100;    new_W = 100*w/h;   }   BufferedImage smallImg = new BufferedImage(new_W,new_H,srcImg.getType());   Graphics g = smallImg.getGraphics();   g.drawImage(srcImg,0,0,new_W,new_H,null);   g.dispose();   return smallImg;  }    /*将字符串保存为.txt文件*/  public void saveAsTxt(String fileName){   try{    PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(fileName)));    for(int i = 0;i<imgString.length();i++){     out.print(imgString.charAt(i));    }    out.close();       }catch(IOException ex){    ex.printStackTrace();   }  }    /*批处理图像文件*/  public static void batchImgFile(String srcfile, String tragetfile){      File folder = new File(tragetfile); //生成图片的文件夹   File srcfolder = new File(srcfile);   if(!folder.exists() || !folder.isDirectory())    folder.mkdirs();   ImageProcesser processer = new ImageProcesser();   File[] filelist = srcfolder.listFiles();      for(int i=0;i<filelist.length;i++){    if(!filelist[i].isFile())     continue;    processer.toBitmapConvert(filelist[i]);    processer.saveAsTxt(tragetfile+"/"+(i+1)+".txt");    System.out.println(filelist[i].getName()+" is converted!");   }   System.out.println("All img were converted!");     }  }