• java 验证码图片处理类,为验证码识别做准备


    /*
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    package snailocr.util;

    import java.awt.Color;
    import java.awt.image.BufferedImage;
    import java.io.File;
    import java.io.IOException;
    import java.util.logging.Level;
    import java.util.logging.Logger;
    import javax.imageio.ImageIO;

    /**
     *
     * @author Administrator
     */
    public class ImageTool {

        private BufferedImage image;
        private int width;
        private int height;

        /**
         * 变图像为黑白色 提示: 黑白化之前最好灰色化以便得到好的灰度平均值,利于获得好的黑白效果
         *
         * @return
         */
        public ImageTool changeToBlackWhiteImage() {
            int avgGrayValue = getAvgValue();
            int whitePoint = getWhitePoint(), blackPoint = getBlackPoint();

            Color point;
            for (int i = 0; i < height; i++) {
                for (int j = 0; j < width; j++) {
                    point = new Color(image.getRGB(j, i));
                    image.setRGB(j, i, (point.getRed() < avgGrayValue ? blackPoint : whitePoint));
                }
            }
            return this;
        }

        /**
         *
         *
         * @param whiteAreaPercent 过滤之后白色区域面积占整个图片面积的最小百分比
         * @param removeLighter true:过滤比中值颜色轻的,false:过滤比中值颜色重的,一般都是true
         * @return
         */
        public ImageTool midddleValueFilter(int whiteAreaMinPercent, boolean removeLighter) {
            int modify = 0;
            int avg = getAvgValue();
            Color point;
            while (getWhitePercent() < whiteAreaMinPercent) {
                for (int i = 0; i < height; i++) {
                    for (int j = 0; j < width; j++) {
                        point = new Color(image.getRGB(j, i));
                        if (removeLighter) {
                            if (((point.getRed() + point.getGreen() + point.getBlue()) / 3) > avg - modify) {
    //                         System.out.println(((point.getRed() + point.getGreen() + point.getBlue()) / 3)+"--"+(avg - modify));
                                image.setRGB(j, i, getWhitePoint());
                            }
                        } else {
                            if (((point.getRed() + point.getGreen() + point.getBlue()) / 3) < avg + modify) {
    //                         System.out.println(((point.getRed() + point.getGreen() + point.getBlue()) / 3)+"--"+(avg - modify));
                                image.setRGB(j, i, getWhitePoint());
                            }
                        }

                    }
                }
                modify++;
            }
    //        System.out.println(getWhitePercent());
            return this;
        }

        private int getWhitePercent() {
            Color point;
            int white = 0;
            for (int i = 0; i < height; i++) {
                for (int j = 0; j < width; j++) {
                    point = new Color(image.getRGB(j, i));
                    if (((point.getRed() + point.getGreen() + point.getBlue()) / 3) == 255) {
                        white++;
                    }
                }
            }
            return (int) Math.ceil(((float) white * 100 / (width * height)));
        }

        /**
         * @param 变图像为灰色 取像素点的rgb三色平均值作为灰度值
         *
         * @return
         */
        public ImageTool changeToGrayImage() {
            int gray;
            Color point;
            for (int i = 0; i < height; i++) {
                for (int j = 0; j < width; j++) {
                    point = new Color(image.getRGB(j, i));
                    gray = (point.getRed() + point.getGreen() + point.getBlue()) / 3;
                    image.setRGB(j, i, new Color(gray, gray, gray).getRGB());
                }
            }
            return this;
        }

        /**
         *
         * 去除噪点和单点组成的干扰线 注意: 去除噪点之前应该对图像黑白化
         *
         * @param neighborhoodMinCount 每个点最少的邻居数
         * @return
         */
        public ImageTool removeBadBlock(int blockWidth, int blockHeight, int neighborhoodMinCount) {
            int val;
            int whitePoint = getWhitePoint();
            int counter, topLeftXIndex, topLeftYIndex;
            for (int y = 0; y < height; y++) {
                for (int x = 0; x < width; x++) {
                    //初始化邻居数为0
                    counter = 0;
                    topLeftXIndex = x - 1;
                    topLeftYIndex = y - 1;
                    //x1 y1是以x,y左上角点为顶点的矩形,该矩形包围在传入的矩形的外围,计算传入的矩形的有效邻居数目
                    if (isBlackBlock(x, y, blockWidth, blockHeight)) {//只有当块是全黑色才计算
                        for (int x1 = topLeftXIndex; x1 <= topLeftXIndex + blockWidth + 1; x1++) {
                            for (int y1 = topLeftYIndex; y1 <= topLeftYIndex + blockHeight + 1; y1++) {
                                //判断这个点是否存在
                                if (x1 < width && x1 >= 0 && y1 < height && y1 >= 0) {
                                    //判断这个点是否是传入矩形的外围点
                                    if (x1 == topLeftXIndex || x1 == topLeftXIndex + blockWidth + 1
                                            || y1 == topLeftYIndex || y1 == topLeftYIndex + blockHeight + 1) {
                                        //这里假定图像已经被黑白化,取Red值认为不是0就是255
                                        val = new Color(image.getRGB(x1, y1)).getRed();
    //                                System.out.println(val + "--" + (centerVal));
                                        //如果这个邻居是黑色,就把中心点的有效邻居数目加一
                                        if (val == 0) {
                                            counter++;
                                        }
                                    }
                                }
                            }
                        }
    //                    System.out.println("-------------------");
    //                System.out.println(x+"-"+y+"-"+counter);
                        if (counter < neighborhoodMinCount) {
                            image.setRGB(x, y, whitePoint);
                        }
                    }
                }
            }
            return this;
        }

        /**
         * 如果点周围的黑点数达到补偿值就把这个点变为黑色
         *
         * @param addFlag 补偿阀值,通过观察处理过的图像确定,一般为2即可
         * @return
         */
        public ImageTool modifyBlank(int addFlag) {
            int val, counter = 0, topLeftXIndex, topLeftYIndex, blackPoint = getBlackPoint();
            Color point;
            for (int y = 0; y < height; y++) {
                for (int x = 0; x < width; x++) {
                    //初始化邻居数为0
                    counter = 0;
                    topLeftXIndex = x - 1;
                    topLeftYIndex = y - 1;
                    point = new Color(image.getRGB(x, y));
                    //这里假定图像已经被黑白化,取Red值认为不是0就是255
                    val = point.getRed();
                    //只有白点才进行补偿
                    if (val == 255) {
                        for (int x1 = topLeftXIndex; x1 <= topLeftXIndex + 2; x1++) {
                            for (int y1 = topLeftYIndex; y1 <= topLeftYIndex + 2; y1++) {
                                //判断这个点是否存在
                                if (x1 < width && x1 >= 0 && y1 < height && y1 >= 0) {
                                    //判断这个点是否是传入点的外围点
                                    if (x1 == topLeftXIndex || x1 == topLeftXIndex + 2
                                            || y1 == topLeftYIndex || y1 == topLeftYIndex + 2) {
                                        //这里假定图像已经被黑白化,取Red值认为不是0就是255
                                        val = new Color(image.getRGB(x1, y1)).getRed();
    //                                System.out.println(val + "--" + (centerVal));
                                        //如果这个邻居是黑色,就把中心点的补偿数目加一
                                        if (val == 0) {
                                            counter++;
                                        }
                                    }
                                }
                            }
                        }
                        //如果这个点周围的黑点数达到补偿值就把这个点变为黑色
                        if (counter >= addFlag) {
                            image.setRGB(x, y, blackPoint);
                        }
                    }
                }
            }
            return this;
        }

        public BufferedImage getBufferedImage(String filename) {
            File file = new File(filename);
            try {
                return ImageIO.read(file);
            } catch (IOException ex) {
                Logger.getLogger(ImageTool.class.getName()).log(Level.SEVERE, null, ex);
                return null;
            }
        }

        private boolean isBlackBlock(int startX, int startY, int blockWidth, int blockHeight) {
            int counter = 0;//统计黑色像素点的个数
            int total = 0;//统计有效像素点的个数
            int val;
            for (int x1 = startX; x1 <= startX + blockWidth - 1; x1++) {
                for (int y1 = startY; y1 <= startY + blockHeight - 1; y1++) {
                    //判断这个点是否存在
                    if (x1 < width && x1 >= 0 && y1 < height && y1 >= 0) {
                        total++;//有效像素点的个数
                        //这里假定图像已经被黑白化,取Red值认为不是0就是255
                        val = new Color(image.getRGB(x1, y1)).getRed();
                        //如果这个点是黑色,就把黑色像素点的数目加一
                        if (val == 0) {
                            counter++;
                        }
                    }
                }
            }
    //        System.out.println(startX + "--" + startY + "" + (counter == total&&total!=0));
            return counter == total && total != 0;
        }

        private int getWhitePoint() {
            return (new Color(255, 255, 255).getRGB() & 0xffffffff);
        }

        private int getBlackPoint() {
            return (new Color(0, 0, 0).getRGB() & 0xffffffff);
        }

        private int getAvgValue() {
            Color point;
            int total = 0;
            for (int i = 0; i < height; i++) {
                for (int j = 0; j < width; j++) {
                    point = new Color(image.getRGB(j, i));
                    total += (point.getRed() + point.getGreen() + point.getBlue()) / 3;
                }
            }
            return total / (width * height);
        }

        public void saveToFile(String filePath) {
            try {
                String ext = filePath.substring(filePath.lastIndexOf(".") + 1);
                File newFile = new File(filePath);
                ImageIO.write(image, ext, newFile);
            } catch (IOException ex) {
                Logger.getLogger(ImageTool.class.getName()).log(Level.SEVERE, null, ex);
            }
        }

        public BufferedImage getImage() {
            return image;
        }

        public void setImage(BufferedImage image) {
            this.image = image;
            width = image.getWidth();
            height = image.getHeight();
        }
    }

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  • 原文地址:https://www.cnblogs.com/Free-Thinker/p/3531919.html
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