本文实例为大家分享了java指纹识别和图片识别源代码，供大家参考，具体内容如下
主类：
import java.awt.image.BufferedImage;
import java.util.ArrayList;
import java.util.List;
public class SimilarImageSearch {
public static void main(String[] args) {
List hashCodes = new ArrayList();
String filename = ImageHelper.path + "\images\";
String hashCode = null;
for (int i = 0; i < 6; i++)
{
hashCode = produceFingerPrint(filename + "example" + (i + 1) + ".jpg");
hashCodes.add(hashCode);
}
System.out.println("Resources: ");
System.out.println(hashCodes);
System.out.println();
String sourceHashCode = produceFingerPrint(filename + "source.jpg");
System.out.println("Source: ");
System.out.println(sourceHashCode);
System.out.println();
for (int i = 0; i < hashCodes.size(); i++)
{
int difference = hammingDistance(sourceHashCode, hashCodes.get(i));
System.out.print("汉明距离:"+difference+" ");
if(difference==0){
System.out.println("source.jpg图片跟example"+(i+1)+".jpg一样");
}else if(difference<=5){
System.out.println("source.jpg图片跟example"+(i+1)+".jpg非常相似");
}else if(difference<=10){
System.out.println("source.jpg图片跟example"+(i+1)+".jpg有点相似");
}else if(difference>10){
System.out.println("source.jpg图片跟example"+(i+1)+".jpg完全不一样");
}
}
}
public static int hammingDistance(String sourceHashCode, String hashCode) {
int difference = 0;
int len = sourceHashCode.length();
for (int i = 0; i < len; i++) {
if (sourceHashCode.charAt(i) != hashCode.charAt(i)) {
difference ++;
}
}
return difference;
}
public static String produceFingerPrint(String filename) {
BufferedImage source = ImageHelper.readPNGImage(filename);// 读取文件
int width = 8;
int height = 8;
// 第一步，缩小尺寸。
// 将图片缩小到8x8的尺寸，总共64个像素。这一步的作用是去除图片的细节，只保留结构、明暗等基本信息，摒弃不同尺寸、比例带来的图片差异。
BufferedImage thumb = ImageHelper.thumb(source, width, height, false);
// 第二步，简化色彩。
// 将缩小后的图片，转为64级灰度。也就是说，所有像素点总共只有64种颜色。
int[] pixels = new int[width * height];
for (int i = 0; i < width; i++) {
for (int j = 0; j < height; j++) {
pixels[i * height + j] = ImageHelper.rgbToGray(thumb.getRGB(i, j));
}
}
// 第三步，计算平均值。
// 计算所有64个像素的灰度平均值。
int avgPixel = ImageHelper.average(pixels);
// 第四步，比较像素的灰度。
// 将每个像素的灰度，与平均值进行比较。大于或等于平均值，记为1；小于平均值，记为0。
int[] comps = new int[width * height];
for (int i = 0; i < comps.length; i++) {
if (pixels[i] >= avgPixel) {
comps[i] = 1;
} else {
comps[i] = 0;
}
}
// 第五步，计算哈希值。
// 将上一步的比较结果，组合在一起，就构成了一个64位的整数，这就是这张图片的指纹。组合的次序并不重要，只要保证所有图片都采用同样次序就行了。
StringBuffer hashCode = new StringBuffer();
for (int i = 0; i < comps.length; i+= 4) {
int result = comps[i] * (int) Math.pow(2, 3) + comps[i + 1] * (int) Math.pow(2, 2) + comps[i + 2] * (int) Math.pow(2, 1) + comps[i + 2];
hashCode.append(binaryToHex(result));
}
// 得到指纹以后，就可以对比不同的图片，看看64位中有多少位是不一样的。
return hashCode.toString();
}
private static char binaryToHex(int binary) {
char ch = ' ';
switch (binary)
{
case 0:
ch = '0';
break;
case 1:
ch = '1';
break;
case 2:
ch = '2';
break;
case 3:
ch = '3';
break;
case 4:
ch = '4';
break;
case 5:
ch = '5';
break;
case 6:
ch = '6';
break;
case 7:
ch = '7';
break;
case 8:
ch = '8';
break;
case 9:
ch = '9';
break;
case 10:
ch = 'a';
break;
case 11:
ch = 'b';
break;
case 12:
ch = 'c';
break;
case 13:
ch = 'd';
break;
case 14:
ch = 'e';
break;
case 15:
ch = 'f';
break;
default:
ch = ' ';
}
return ch;
}
}
工具类：
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.ImageIO;
import com.sun.image.codec.jpeg.ImageFormatException;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageDecoder;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
public class ImageHelper {
// 项目根目录路径
public static final String path = System.getProperty("user.dir");
public static BufferedImage thumb(BufferedImage source, int width,
int height, boolean b) {
// targetW，targetH分别表示目标长和宽
int type = source.getType();
BufferedImage target = null;
double sx = (double) width / source.getWidth();
double sy = (double) height / source.getHeight();
if (b) {
if (sx > sy) {
sx = sy;
width = (int) (sx * source.getWidth());
} else {
sy = sx;
height = (int) (sy * source.getHeight());
}
}
if (type == BufferedImage.TYPE_CUSTOM) { // handmade
ColorModel cm = source.getColorModel();
WritableRaster raster = cm.createCompatibleWritableRaster(width,
height);
boolean alphaPremultiplied = cm.isAlphaPremultiplied();
target = new BufferedImage(cm, raster, alphaPremultiplied, null);
} else
target = new BufferedImage(width, height, type);
Graphics2D g = target.createGraphics();
// smoother than exlax:
g.setRenderingHint(RenderingHints.KEY_RENDERING,
RenderingHints.VALUE_RENDER_QUALITY);
g.drawRenderedImage(source, AffineTransform.getScaleInstance(sx, sy));
g.dispose();
return target;
}
public static void waterMark(String imgPath, String markPath, int x, int y,
float alpha) {
try {
// 加载待处理图片文件
Image img = ImageIO.read(new File(imgPath));
BufferedImage image = new BufferedImage(img.getWidth(null),
img.getHeight(null), BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.drawImage(img, 0, 0, null);
// 加载水印图片文件
Image src_biao = ImageIO.read(new File(markPath));
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
alpha));
g.drawImage(src_biao, x, y, null);
g.dispose();
// 保存处理后的文件
FileOutputStream out = new FileOutputStream(imgPath);
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
encoder.encode(image);
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public static void textMark(String imgPath, String text, Font font,
Color color, int x, int y, float alpha) {
try {
Font Dfont = (font == null) ? new Font("宋体", 20, 13) : font;
Image img = ImageIO.read(new File(imgPath));
BufferedImage image = new BufferedImage(img.getWidth(null),
img.getHeight(null), BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.drawImage(img, 0, 0, null);
g.setColor(color);
g.setFont(Dfont);
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
alpha));
g.drawString(text, x, y);
g.dispose();
FileOutputStream out = new FileOutputStream(imgPath);
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
encoder.encode(image);
out.close();
} catch (Exception e) {
System.out.println(e);
}
}
public static BufferedImage readJPEGImage(String filename)
{
try {
InputStream imageIn = new FileInputStream(new File(filename));
// 得到输入的编码器，将文件流进行jpg格式编码
JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(imageIn);
// 得到编码后的图片对象
BufferedImage sourceImage = decoder.decodeAsBufferedImage();
return sourceImage;
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (ImageFormatException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
public static BufferedImage readPNGImage(String filename)
{
try {
File inputFile = new File(filename);
BufferedImage sourceImage = ImageIO.read(inputFile);
return sourceImage;
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (ImageFormatException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
public static int rgbToGray(int pixels) {
// int _alpha = (pixels >> 24) & 0xFF;
int _red = (pixels >> 16) & 0xFF;
int _green = (pixels >> 8) & 0xFF;
int _blue = (pixels) & 0xFF;
return (int) (0.3 * _red + 0.59 * _green + 0.11 * _blue);
}
public static int average(int[] pixels) {
float m = 0;
for (int i = 0; i < pixels.length; ++i) {
m += pixels[i];
}
m = m / pixels.length;
return (int) m;
}
}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持考高分网。
