JAVA简单二值化图像处理

package downloadimg;

import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

/**
* @author Cytosine
* @thanks Wizard,BreakShadow
*/
public class SimpleBinarization {
public static void main(String args[]){
for(int i=0;i<100;i++){
BufferedImage bi=httpsGetImg(httpsGetImgURL());
int width=bi.getWidth();
int height=bi.getHeight();
int pixel;
BufferedImage binary=new BufferedImage(width,height,BufferedImage.TYPE_BYTE_BINARY);
for(int minx=bi.getMinX();minx<width;minx++){
for(int miny=bi.getMinY();miny<height;miny++){
pixel=bi.getRGB(minx, miny);
if(pixel==-1){//此时为白色/透明背景
binary.setRGB(minx, miny, Color.WHITE.getRGB());
}else{
binary.setRGB(minx, miny, Color.BLACK.getRGB());
}
}
}
String p="D:\\TEST\\"+i+".png";
File f=new File(p);
try {
ImageIO.write(bi, "png", f);
} catch (IOException ex) {
Logger.getLogger(SimpleBinarization.class.getName()).log(Level.SEVERE, null, ex);
}
String path="D:\\TEST\\"+i+"b.png";
File file=new File(path);
try {
ImageIO.write(binary, "png", file);
} catch (IOException ex) {
Logger.getLogger(SimpleBinarization.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
public static String httpsGetImgURL(){
StringBuffer requestResult=new StringBuffer();
BufferedReader bufferedReader=null;
try{
SSLContext ssl=SSLContext.getInstance("TLS");
ssl.init(null, new TrustManager[]{cytoX509TrustManager}, null);
URL url=new URL("https://passport.baidu.com/v2/?reggetcodestr");
HttpsURLConnection conn=(HttpsURLConnection)url.openConnection();
conn.setSSLSocketFactory(ssl.getSocketFactory());
conn.setRequestMethod("GET");
conn.setDoOutput(true);
conn.connect();
bufferedReader=new BufferedReader(new InputStreamReader(conn.getInputStream()));
}catch(Exception ex){
ex.printStackTrace();
}
try{
String line;
while((line=bufferedReader.readLine())!=null){
requestResult.append(line);
}
bufferedReader.close();
}catch(Exception ex){
ex.printStackTrace();
}
String all=requestResult.toString();
String[] spl=all.split("'");
String verifystr=spl[3];
String result="https://passport.baidu.com/cgi-bin/genimage?"+verifystr;
return result;
}
public static BufferedImage httpsGetImg(String url){
BufferedInputStream bufferedInputStream=null;
ByteArrayOutputStream byteArrayOutputStream=new ByteArrayOutputStream();
try{
SSLContext ssl=SSLContext.getInstance("TLS");
ssl.init(null, new TrustManager[]{cytoX509TrustManager}, null);
URL realURL=new URL(url);
HttpsURLConnection conn=(HttpsURLConnection)realURL.openConnection();
conn.setSSLSocketFactory(ssl.getSocketFactory());
conn.setRequestMethod("GET");
conn.connect();
bufferedInputStream=new BufferedInputStream(conn.getInputStream());
}catch(Exception ex){
ex.printStackTrace();
}
try{
int b;
while((b=bufferedInputStream.read())!=-1){
byteArrayOutputStream.write(b);
}
bufferedInputStream.close();
}catch(Exception ex){
ex.printStackTrace();
}
byte[] imgData=byteArrayOutputStream.toByteArray();
ByteArrayInputStream in=new ByteArrayInputStream(imgData);
BufferedImage result=null;
try {
result = ImageIO.read(in);
} catch (IOException ex) {
Logger.getLogger(DownloadImgWithoutType.class.getName()).log(Level.SEVERE, null, ex);
}
return result;
}
//https证书
private static X509TrustManager cytoX509TrustManager=new X509TrustManager(){

public X509Certificate[] getAcceptedIssuers(){
return null;
}

@Override
public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
}

@Override
public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
}
};
}