java扫描图片代码 图像识别代码java

java利用pc扫描二维码代码，求大神帮忙啊！！！

一般来说都会有个设备，设备会把扫描结果反馈的。

你需要确认的是设备是否有jar包提供访问，如果没有的话就要使用jni访问了dll了。

还有一种情况是扫描设备就是模拟键盘输入的。这样你什么都不用做，在输入框里等用户扫描就好了。

相关问答

Q1: 用Java直接从扫描仪获得扫描数据，然后上载到服务器上，这样的程序需要利用那些知识点（有关Java）？

package edu.ctgu.JTwacker;

import java.awt.BorderLayout;

import java.awt.Cursor;

import java.awt.Dimension;

import java.awt.Graphics;

import java.awt.Rectangle;

import java.awt.Toolkit;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import java.awt.event.WindowListener;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileInputStream;

import javax.swing.JButton;

import javax.swing.JComboBox;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.JScrollPane;

import javax.swing.JToolBar;

import javax.swing.SwingUtilities;

import com.sun.image.codec.jpeg.JPEGCodec;

import com.sun.image.codec.jpeg.JPEGImageDecoder;

import edu.ctgu.twain.JTwain;

/*

这是显示扫描图片的frame

*/

public class JTwacker extends JFrame {

class JPEGPanel extends JPanel {

/** Image for the inner class

*/

protected BufferedImage mJPEGPanelBufferedImage;

/** Pnale to diaply the image

*/

public JPEGPanel() {

// no op

}

/** Sets the bufferedimage into the class

* @param bi BufferedImage

*/

public void setBufferedImage(BufferedImage bi) {

if (bi == null) {

return;

}

mJPEGPanelBufferedImage = bi;

Dimension d = new Dimension(mJPEGPanelBufferedImage.getWidth(this),

mJPEGPanelBufferedImage.getHeight(this));

setPreferredSize(d);

revalidate();

repaint();

}

/** Paints the component.

* @param g Graphics object used for the painting

*/

public void paintComponent(Graphics g) {

super.paintComponent(g);

Dimension d = getSize();

g.setColor(getBackground());

g.fillRect(0, 0, d.width, d.height);

if (mJPEGPanelBufferedImage != null) {

g.drawImage(mJPEGPanelBufferedImage, 0, 0, this);

}

}

}

protected JPEGPanel mJpegPanel;

protected BufferedImage mBufferedImage;

protected JComboBox mSourcesCombo;

protected JToolBar mToolBar;

/** Constructor

*/

public JTwacker() {

super("测试");

mJpegPanel = new JPEGPanel();

JScrollPane ps = new JScrollPane(mJpegPanel,

JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,

JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);

getContentPane().add(ps, BorderLayout.CENTER);

WindowListener wndCloser = new WindowAdapter() {

public void windowClosing(WindowEvent e) {

System.exit(0);

}

};

addWindowListener(wndCloser);

mToolBar = new JToolBar("Twain");

mToolBar.setFloatable(false);

addButtons();

getContentPane().add(mToolBar, BorderLayout.NORTH);

setSize(800, 600);

/* Center the frame */

Dimension screenDim = Toolkit.getDefaultToolkit().getScreenSize();

Rectangle frameDim = getBounds();

setLocation(

(screenDim.width - frameDim.width) / 2,

(screenDim.height - frameDim.height) / 2

);

setVisible(true);

}

protected void addButtons(){

JButton _ab = new JButton("扫描");

_ab.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

acquireImage();

}

});

mToolBar.add(_ab);

mToolBar.addSeparator();

if (edu.ctgu.twain.JTwain.getInstance().isTwainAvailble()) {

String[] twainSources = JTwain.getInstance().getAvailableSources();

if (twainSources != null) {

mSourcesCombo = new JComboBox(twainSources);

} else {

mSourcesCombo = new JComboBox();

mSourcesCombo.addItem("NONE AVAILABLE");

}

} else {

mSourcesCombo = new JComboBox();

mSourcesCombo.addItem("NONE AVAILABLE");

}

mToolBar.add(mSourcesCombo);

}

protected void acquireImage() {

if (JTwain.getInstance().isTwainAvailble()){

if (mSourcesCombo.getItemCount() 0 ){

String _source = (String)mSourcesCombo.getSelectedItem();

if (_source != null){

String _filename = JTwain.getInstance().acquire(_source);

System.out.println(_filename);

if (_filename != null _filename.length() 0) {

File fChoosen = new File(_filename);

// savetofile(fChoosen);

showImage(fChoosen);

} else {

System.out.println("哎呀，怎么出错了！");

}

} // end if

} // end if

} // end if

}

protected void showImage(final File file) {

if (file == null || !file.exists()) {

return;

}

setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));

Thread runner = new Thread() {

public void run() {

try {

FileInputStream in = new FileInputStream(file);

JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(in);

mBufferedImage = decoder.decodeAsBufferedImage();

in.close();

SwingUtilities.invokeLater( new Runnable() {

public void run() {

reset();

}

});

}

catch (Exception ex) {

ex.printStackTrace();

}

setCursor(Cursor.getPredefinedCursor( Cursor.DEFAULT_CURSOR));

}

};

runner.start();

}

//把扫描得到的图片保存为文件，然后上传到服务器或保存到数据库中

protected void savetofile(final File file) {

try {

File mfile=new File("c:\\dd.jpg");

if (mfile.exists()) {

mfile.delete();

}else {

file.renameTo(mfile);

}

} catch (Exception e) {

e.printStackTrace();

// TODO: handle exception

}

}

protected void reset() {

if (mBufferedImage != null) {

mJpegPanel.setBufferedImage(mBufferedImage);

}

}

public static void main(String argv[]) {

new JTwacker();

}

}

-------------------------

package edu.ctgu.twain;

/*

这是调用动态链接库的类

*/

public class JTwain {

private static final JTwain mInstance = new JTwain();

protected final String DLL_NAME = "jtwain";

private JTwain() {

initLib();

}

public static JTwain getInstance(){

return mInstance;

}

public native boolean isTwainAvailble();

public native String[] getAvailableSources();

public native String acquire();

public native String acquire(String sourceName);

private void initLib(){

try {

System.loadLibrary(DLL_NAME);

}catch(Exception e) {

e.printStackTrace();

}

finally {

// System.out.println("Loading : " + DLL_NAME + ".dll");

}

}

}

Q2: java编辑一个扫描文件的方法，要求可以扫描根目录下的所有文件

package com.sunjob;

import java.io.File;

import java.util.ArrayList;

import java.util.Collection;

public class Js {

/**

* @param args

*/

//初始化n，用于计数

static int n=0;

public static void get(File file) {

try {

//判断文件是否是文件，如果是文件，获取路径，并计数

if(file.isFile())

{

n++;

System.out.println(file.getAbsolutePath());

}

else

{

//如果是文件夹，声明一个数组放文件夹和他的子文件

File[] f=file.listFiles();

//遍历文件件下的文件，并获取路径

for (File file2 : f) {

get(file2);

}

}

} catch (RuntimeException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static void main(String[] args) {

// TODO Auto-generated method stub

这是扫描c盘的所有文件，可以修改

File file=new File("c:\\");

get(file);

System.out.println("文件个数为："+n);

}

}

Q3: 如何在Java中调用扫描仪的源代码

下载一个jar包，放在lib目录下面，然后再把这个jar加入到项目里面就可以了，右键add as libary,就可以引用源代码了