java图像处理方法：灰度化，二值化，降噪，切割，裁剪，找相似等

package com.bdfus.piper.common.util.image; import java.awt.Color; import java.awt.Rectangle; import java.awt.image.BufferedImage; import java.util.ArrayList; import java.util.List; /** * 已经二值化后的图片通过x,y投影实现切割，无粘连情况下效果很好 * @ClassName: CutImg * @Description:TODO(这里用一句话描述这个类的作用) * @author: chenyang * @date: 2017年9月15日 下午5:02:25 * */ public class CutImg { /** * 图像向x轴做投影后的数组 * * @param imagedata * @param w * @param h * @return */ public static int[] xpro(BufferedImage input, int w, int h) { int xpro[] = new int[w]; for (int j = 0; j < w; j++) { for (int i = 0; i < h; i++) { if (input.getRGB(j, i) !=-1) xpro[j]++; } } return xpro; } /** * 基于x投影后再进行y轴投影 * * @param imagedata * @param w * @param h * @return */ public static int[] ypro(BufferedImage input, Rectangle xRectangle) { int ypro[] = new int[(int) xRectangle.getHeight()]; int w = (int) xRectangle.getWidth(); int h = (int) xRectangle.getHeight(); for (int y = (int) xRectangle.getY(); y < h; y++) { for (int x = (int) xRectangle.getX(); x < xRectangle.getX()+w; x++) { if (input.getRGB(x, y) !=-1) ypro[y]++; } } return ypro; } public static BufferedImage verticalProjection(int[] xpro, BufferedImage input){ BufferedImage out = new BufferedImage(input.getWidth(), input.getHeight(), input.getType()); for (int i = 0; i < input.getHeight(); i++) { for (int j = 0; j < input.getWidth(); j++) { int color = new Color(255, 255, 255).getRGB(); //背景设置为白色。 out.setRGB(j, i, color); } } /*将直方图的曲线设为黑色*/ for (int i = 0; i < input.getWidth(); i++) { for (int j = 0; j < xpro[i]; j++) { int color = new Color(0, 0, 0).getRGB(); //直方图设置为黑色 out.setRGB(i, j, color); } } return out; } public static BufferedImage yVerticalProjection(int[] ypro, BufferedImage input){ BufferedImage out = new BufferedImage(input.getWidth(), input.getHeight(), input.getType()); for (int i = 0; i < input.getHeight(); i++) { for (int j = 0; j < input.getWidth(); j++) { int color = new Color(255, 255, 255).getRGB(); //背景设置为白色。 out.setRGB(j, i, color); } } /*将直方图的曲线设为黑色*/ for (int y = 0; y < input.getHeight(); y++) { for (int x = 0; x < ypro[y]; x++) { int color = new Color(0, 0, 0).getRGB(); //直方图设置为黑色 out.setRGB(x, y, color); } } return out; } /** * 简单的基于投影的图像分割 * @param xpro * @param w * @param h * @return */ public static Rectangle[] xproSegment(BufferedImage input, int[] xpro, int FZ) { List<Rectangle> c = new ArrayList<Rectangle>();//用于储存分割出来的每个字符 int startIndex = 0;//记录进入字符区的索引 int endIndex = 0;//记录进入空白区域的索引 boolean inBlock = false;//是否遍历到了字符区内 // int totalWidth = 0; for (int i = 0; i < input.getWidth(); ++i) { if (!inBlock && xpro[i] != 0)//进入字符区了 { inBlock = true; startIndex = i; } else if (xpro[i] == 0 && inBlock)//进入空白区了 { endIndex = i; inBlock = false; int width = endIndex-startIndex; if(width>=FZ){ Rectangle rectangle = new Rectangle(startIndex, 0, width, input.getHeight()); c.add(rectangle); // totalWidth+=width; } } } //预处理一下，先将间隔很小的rectangle合并 List<Rectangle> cc = new ArrayList<Rectangle>();//用于储存分割出来的每个字符 for (int i = 1; i <c.size() ; i++){ Rectangle pre = c.get(i-1); Rectangle now = c.get(i); int xspace = (int) now.getX() - (int)(pre.getX()+pre.getWidth()); if(xspace<2 && (now.getWidth()<=FZ || pre.getWidth()<=4)){ //合并 int x = (int)(pre.getX()); int w = (int)(now.getX()-pre.getX()+now.getWidth()); Rectangle newR = new Rectangle(x, 0, w, input.getHeight()); cc.add(newR); }else{ if(i==1){ cc.add(pre); } if(i!=c.size()-1){ Rectangle next = c.get(i+1); int space = (int) next.getX() - (int)(now.getX()+now.getWidth()); if(space>=2 || (now.getWidth()>FZ && next.getWidth()>4)){ cc.add(now); } }else{ cc.add(now); } } } Rectangle result[] = cc.toArray(new Rectangle[]{}); //如果有三个，找出最多的再分割一次 if(result.length==3){ int maxIndex = 0; int maxWidth = (int) result[0].getWidth(); for(int i=0;i<result.length;i++){ Rectangle r = result[i]; if(maxWidth<r.getWidth()){ maxWidth = (int) r.getWidth(); maxIndex = i; } } Rectangle r = result[maxIndex]; int newXpro[] = new int[(int) r.getWidth()]; for(int i=0; i<r.getWidth(); i++){ newXpro[i] = xpro[(int) (i+r.getX())]; } List<Bottom> bottoms = findXproBottom(newXpro,1); if(bottoms!=null && bottoms.size()>0){ Bottom bottom = bottoms.get(0); Rectangle finalResult[] = new Rectangle[4]; Rectangle new1 = new Rectangle((int)result[maxIndex].getX(), 0, bottom.getStartIndex()+1, input.getHeight()); Rectangle new2 = new Rectangle((int)result[maxIndex].getX()+bottom.getStartIndex(), 0, (int)r.getWidth()-bottom.getStartIndex()-1, input.getHeight()); for(int i=0; i<maxIndex; i++){ finalResult[i] = result[i]; } finalResult[maxIndex] = new1; finalResult[maxIndex+1] = new2; for(int i=maxIndex+2; i<4; i++){ finalResult[i] = result[i-1]; } return finalResult; } } //多了一个，将最少那个和旁边的合并 if(result.length==5){ int minIndex = 0; int minWidth = (int) result[0].getWidth(); for(int i=0;i<result.length;i++){ Rectangle r = result[i]; if(minWidth>r.getWidth()){ minWidth = (int) r.getWidth(); minIndex = i; } } //第一个，直接和后面一个合并 if(minIndex==0){ Rectangle r1 = result[0]; Rectangle r2 = result[1]; int newWidth = (int) ((r2.getX()-r1.getX())+r2.getWidth()); Rectangle newr = new Rectangle((int)r1.getX(), 0, newWidth, (int)r1.getHeight()); Rectangle finalResult[] = new Rectangle[4]; finalResult[0] = newr; fin