- 最近一直在开发一个用于自动发帖的工具,用HttpClient模拟客户端浏览器注册发帖。但是碰到了图形验证码的问题了,对单数字的验证码,通过一些OCR引擎,如:tesseract,AspriseOCR很容易解决问题。但碰到如CSDN论坛这中图形验证码就比较麻烦,必须先通过预处理。使图象二值化,黑白灰度,增加亮度。我的代码如下:
- package myfilter;
- import java.io.*;
- import java.awt.image.*;
- import java.awt.geom.AffineTransform;
- import java.awt.color.ColorSpace;
- import java.awt.image.ConvolveOp;
- import java.awt.image.Kernel;
- import java.awt.image.BufferedImage;
- import javax.imageio.ImageIO;
- import java.awt.Toolkit;
- import java.awt.Image;
- public class MyImgFilter {
- BufferedImage image;
- private int iw, ih;
- private int[] pixels;
- public MyImgFilter(BufferedImage image) {
- this.image = image;
- iw = image.getWidth();
- ih = image.getHeight();
- pixels = new int[iw * ih];
- }
- public BufferedImage changeGrey() {
- PixelGrabber pg = new PixelGrabber(image.getSource(), 0, 0, iw, ih, pixels,0, iw);
- try {
- pg.grabPixels();
- } catch (InterruptedException e) {
- e.printStackTrace();
- }
- // 设定二值化的域值,默认值为100
- int grey = 100;
- // 对图像进行二值化处理,Alpha值保持不变
- ColorModel cm = ColorModel.getRGBdefault();
- for (int i = 0; i < iw * ih; i++) {
- int red, green, blue;
- int alpha = cm.getAlpha(pixels[i]);
- if (cm.getRed(pixels[i]) > grey) {
- red = 255;
- } else {
- red = 0;
- }
- if (cm.getGreen(pixels[i]) > grey) {
- green = 255;
- } else {
- green = 0;
- }
- if (cm.getBlue(pixels[i]) > grey) {
- blue = 255;
- } else {
- blue = 0;
- }
- pixels[i] = alpha << 24 | red << 16 | green << 8 | blue; //通过移位重新构成某一点像素的RGB值
- }
- // 将数组中的象素产生一个图像
- Image tempImg=Toolkit.getDefaultToolkit().createImage(new MemoryImageSource(iw,ih, pixels, 0, iw));
- image = new BufferedImage(tempImg.getWidth(null),tempImg.getHeight(null), BufferedImage.TYPE_INT_BGR );
- image.createGraphics().drawImage(tempImg, 0, 0, null);
- return image;
- }
- public BufferedImage getMedian() {
- PixelGrabber pg = new PixelGrabber(image.getSource(), 0, 0, iw, ih,
- pixels,
- 0, iw);
- try {
- pg.grabPixels();
- } catch (InterruptedException e) {
- e.printStackTrace();
- }
- // 对图像进行中值滤波,Alpha值保持不变
- ColorModel cm = ColorModel.getRGBdefault();
- for (int i = 1; i < ih - 1; i++) {
- for (int j = 1; j < iw - 1; j++) {
- int red, green, blue;
- int alpha = cm.getAlpha(pixels[i * iw + j]);
- // int red2 = cm.getRed(pixels[(i - 1) * iw + j]);
- int red4 = cm.getRed(pixels[i * iw + j - 1]);
- int red5 = cm.getRed(pixels[i * iw + j]);
- int red6 = cm.getRed(pixels[i * iw + j + 1]);
- // int red8 = cm.getRed(pixels[(i + 1) * iw + j]);
- // 水平方向进行中值滤波
- if (red4 >= red5) {
- if (red5 >= red6) {
- red = red5;
- } else {
- if (red4 >= red6) {
- red = red6;
- } else {
- red = red4;
- }
- }
- } else {
- if (red4 > red6) {
- red = red4;
- } else {
- if (red5 > red6) {
- red = red6;
- } else {
- red = red5;
- }
- }
- }
- int green4 = cm.getGreen(pixels[i * iw + j - 1]);
- int green5 = cm.getGreen(pixels[i * iw + j]);
- int green6 = cm.getGreen(pixels[i * iw + j + 1]);
- // 水平方向进行中值滤波
- if (green4 >= green5) {
- if (green5 >= green6) {
- green = green5;
- } else {
- if (green4 >= green6) {
- green = green6;
- } else {
- green = green4;
- }
- }
- } else {
- if (green4 > green6) {
- green = green4;
- } else {
- if (green5 > green6) {
- green = green6;
- } else {
- green = green5;
- }
- }
- }
- // int blue2 = cm.getBlue(pixels[(i - 1) * iw + j]);
- int blue4 = cm.getBlue(pixels[i * iw + j - 1]);
- int blue5 = cm.getBlue(pixels[i * iw + j]);
- int blue6 = cm.getBlue(pixels[i * iw + j + 1]);
- // int blue8 = cm.getBlue(pixels[(i + 1) * iw + j]);
- // 水平方向进行中值滤波
- if (blue4 >= blue5) {
- if (blue5 >= blue6) {
- blue = blue5;
- } else {
- if (blue4 >= blue6) {
- blue = blue6;
- } else {
- blue = blue4;
- }
- }
- } else {
- if (blue4 > blue6) {
- blue = blue4;
- } else {
- if (blue5 > blue6) {
- blue = blue6;
- } else {
- blue = blue5;
- }
- }
- }
- pixels[i * iw +
- j] = alpha << 24 | red << 16 | green << 8 | blue;
- }
- }
- // 将数组中的象素产生一个图像
- Image tempImg=Toolkit.getDefaultToolkit().createImage(new MemoryImageSource(iw,ih, pixels, 0, iw));
- image = new BufferedImage(tempImg.getWidth(null),tempImg.getHeight(null), BufferedImage.TYPE_INT_BGR );
- image.createGraphics().drawImage(tempImg, 0, 0, null);
- return image;
- }
- public BufferedImage getGrey() {
- ColorConvertOp ccp=new ColorConvertOp(ColorSpace.getInstance(ColorSpace.CS_GRAY), null);
- return image=ccp.filter(image,null);
- }
- //Brighten using a linear formula that increases all color values
- public BufferedImage getBrighten() {
- RescaleOp rop=new RescaleOp(1.25f, 0, null);
- return image=rop.filter(image,null);
- }
- //Blur by "convolving" the image with a matrix
- public BufferedImage getBlur() {
- float[] data = {
- .1111f, .1111f, .1111f,
- .1111f, .1111f, .1111f,
- .1111f, .1111f, .1111f, };
- ConvolveOp cop = new ConvolveOp(new Kernel(3, 3, data));
- return image=cop.filter(image,null);
- }
- // Sharpen by using a different matrix
- public BufferedImage getSharpen() {
- float[] data = {
- 0.0f, -0.75f, 0.0f,
- -0.75f, 4.0f, -0.75f,
- 0.0f, -0.75f, 0.0f};
- ConvolveOp cop = new ConvolveOp(new Kernel(3, 3, data));
- return image=cop.filter(image,null);
- }
- // 11) Rotate the image 180 degrees about its center point
- public BufferedImage getRotate() {
- AffineTransformOp atop=new AffineTransformOp(AffineTransform.getRotateInstance(Math.PI,image.getWidth()/2,image.getHeight()/2),
- AffineTransformOp.TYPE_NEAREST_NEIGHBOR);
- return image=atop.filter(image,null);
- }
- public BufferedImage getProcessedImg()
- {
- return image;
- }
- public static void main(String[] args) throws IOException {
- FileInputStream fin=new FileInputStream(args[0]);
- BufferedImage bi=ImageIO.read(fin);
- MyImgFilter flt=new MyImgFilter(bi);
- flt.changeGrey();
- flt.getGrey();
- flt.getBrighten();
- bi=flt.getProcessedImg();
- String pname=args[0].substring(0,args[0].lastIndexOf("."));
- File file = new File(pname+".jpg");
- ImageIO.write(bi, "jpg", file);
- }
- }
- 运行java myfilter.MyImgFilter t6.bmp,请确认图片t6.bmp与myfilter目录在同一目录下。
- 顺便说一下,在JDK1.5下,ImageIO可以输出JPG,BMP,PNG三种格式图片,但不支持GIF图片输出。
- //该片段来自于http://www.codesnippet.cn/detail/1812201411329.html
来源: http://www.codesnippet.cn/detail/1812201411329.html