packagecom.aliyun.picture.demo;/*** @BelongsProject: maven-demo
* @BelongsPackage: com.aliyun.picture.demo
* @Author: Guoyh
* @CreateTime: -10-12 15:05
* @Description: 感知哈希算法(均值哈希算法)比较两图的相似性*/
importjavax.imageio.ImageIO;importjava.awt.Graphics;importjava.awt.Image;importjava.awt.color.ColorSpace;importjava.awt.image.BufferedImage;importjava.awt.image.ColorConvertOp;importjava.util.Arrays;importjava.io.File;public final classFingerPrint {/*** 图像指纹的尺寸,将图像resize到指定的尺寸，来计算哈希数组*/
private static final int HASH_SIZE = 16;/*** 保存图像指纹的二值化矩阵*/
private final byte[] binaryzationMatrix;public FingerPrint(byte[] hashValue) {if (hashValue.length != HASH_SIZE *HASH_SIZE) {throw new IllegalArgumentException(String.format("length of hashValue must be %d", HASH_SIZE *HASH_SIZE));
}this.binaryzationMatrix =hashValue;
}publicFingerPrint(String hashValue) {this(toBytes(hashValue));
}publicFingerPrint(BufferedImage src) {this(hashValue(src));
}private static byte[] hashValue(BufferedImage src) {
BufferedImage hashImage=resize(src, HASH_SIZE, HASH_SIZE);byte[] matrixGray = (byte[]) toGray(hashImage).getData().getDataElements(0, 0, HASH_SIZE, HASH_SIZE, null);returnbinaryzation(matrixGray);
}/*** 从压缩格式指纹创建{@linkFingerPrint}对象
*
*@paramcompactValue
*@return
*/
public static FingerPrint createFromCompact(byte[] compactValue) {return newFingerPrint(uncompact(compactValue));
}public static boolean validHashValue(byte[] hashValue) {if (hashValue.length !=HASH_SIZE) {return false;
}for (byteb : hashValue) {
{if (0 != b && 1 !=b) {return false;
}
}
}return true;
}public static booleanvalidHashValue(String hashValue) {if (hashValue.length() !=HASH_SIZE) {return false;
}for (int i = 0; i < hashValue.length(); ++i) {if ('0' != hashValue.charAt(i) && '1' !=hashValue.charAt(i)) {return false;
}
}return true;
}public byte[] compact() {returncompact(binaryzationMatrix);
}/*** 指纹数据按位压缩
*
*@paramhashValue
*@return
*/
private static byte[] compact(byte[] hashValue) {byte[] result = new byte[(hashValue.length + 7) >> 3];byte b = 0;for (int i = 0; i < hashValue.length; ++i) {if (0 == (i & 7)) {
b= 0;
}if (1 ==hashValue[i]) {
b|= 1 << (i & 7);
}else if (hashValue[i] != 0) {throw new IllegalArgumentException("invalid hashValue,every element must be 0 or 1");
}if (7 == (i & 7) || i == hashValue.length - 1) {
result[i>> 3] =b;
}
}returnresult;
}/*** 压缩格式的指纹解压缩
*
*@paramcompactValue
*@return
*/
private static byte[] uncompact(byte[] compactValue) {byte[] result = new byte[compactValue.length << 3];for (int i = 0; i < result.length; ++i) {if ((compactValue[i >> 3] & (1 << (i & 7))) == 0) {
result[i]= 0;
}else{
result[i]= 1;
}
}returnresult;
}/*** 字符串类型的指纹数据转为字节数组
*
*@paramhashValue
*@return
*/
private static byte[] toBytes(String hashValue) {
hashValue= hashValue.replaceAll("\\s", "");byte[] result = new byte[hashValue.length()];for (int i = 0; i < result.length; ++i) {char c =hashValue.charAt(i);if ('0' ==c) {
result[i]= 0;
}else if ('1' ==c) {
result[i]= 1;
}else{throw new IllegalArgumentException("invalid hashValue String");
}
}returnresult;
}/*** 缩放图像到指定尺寸
*
*@paramsrc
*@paramwidth
*@paramheight
*@return
*/
private static BufferedImage resize(Image src, int width, intheight) {
BufferedImage result= newBufferedImage(width, height,
BufferedImage.TYPE_3BYTE_BGR);
Graphics g=result.getGraphics();try{
g.drawImage(src.getScaledInstance(width, height, Image.SCALE_SMOOTH),0, 0, null);
}finally{
g.dispose();
}returnresult;
}/*** 计算均值
*
*@paramsrc
*@return
*/
private static int mean(byte[] src) {long sum = 0;//将数组元素转为无符号整数
for (byteb : src) {
sum+= (long) b & 0xff;
}return (int) (Math.round((float) sum /src.length));
}/*** 二值化处理
*
*@paramsrc
*@return
*/
private static byte[] binaryzation(byte[] src) {byte[] dst =src.clone();int mean =mean(src);for (int i = 0; i < dst.length; ++i) {//将数组元素转为无符号整数再比较
dst[i] = (byte) (((int) dst[i] & 0xff) >= mean ? 1 : 0);
}returndst;
}/*** 转灰度图像
*
*@paramsrc
*@return
*/
private staticBufferedImage toGray(BufferedImage src) {if (src.getType() ==BufferedImage.TYPE_BYTE_GRAY) {returnsrc;
}else{//图像转灰
BufferedImage grayImage = newBufferedImage(src.getWidth(), src.getHeight(),
BufferedImage.TYPE_BYTE_GRAY);new ColorConvertOp(ColorSpace.getInstance(ColorSpace.CS_GRAY), null).filter(src, grayImage);returngrayImage;
}
}
@OverridepublicString toString() {return toString(true);
}/***@parammultiLine 是否分行
*@return
*/
public String toString(booleanmultiLine) {
StringBuffer buffer= newStringBuffer();int count = 0;for (byte b : this.binaryzationMatrix) {
buffer.append(0 == b ? '0' : '1');if (multiLine && ++count % HASH_SIZE == 0) {
buffer.append('\n');
}
}returnbuffer.toString();
}
@Overridepublic booleanequals(Object obj) {if (obj instanceofFingerPrint) {return Arrays.equals(this.binaryzationMatrix, ((FingerPrint) obj).binaryzationMatrix);
}else{return super.equals(obj);
}
}/*** 与指定的压缩格式指纹比较相似度
*
*@paramcompactValue
*@return*@see#compare(FingerPrint)*/
public float compareCompact(byte[] compactValue) {returncompare(createFromCompact(compactValue));
}/***@paramhashValue
*@return*@see#compare(FingerPrint)*/
public floatcompare(String hashValue) {return compare(newFingerPrint(hashValue));
}/*** 与指定的指纹比较相似度
*
*@paramhashValue
*@return*@see#compare(FingerPrint)*/
public float compare(byte[] hashValue) {return compare(newFingerPrint(hashValue));
}/*** 与指定图像比较相似度
*
*@paramimage2
*@return*@see#compare(FingerPrint)*/
public floatcompare(BufferedImage image2) {return compare(newFingerPrint(image2));
}/*** 比较指纹相似度
*
*@paramsrc
*@return*@see#compare(byte[], byte[])*/
public floatcompare(FingerPrint src) {if (src.binaryzationMatrix.length != this.binaryzationMatrix.length) {throw new IllegalArgumentException("length of hashValue is mismatch");
}returncompare(binaryzationMatrix, src.binaryzationMatrix);
}/*** 判断两个数组相似度，数组长度必须一致否则抛出异常
*
*@paramf1
*@paramf2
*@return返回相似度(0.0 ~ 1.0)*/
private static float compare(byte[] f1, byte[] f2) {if (f1.length !=f2.length) {throw new IllegalArgumentException("mismatch FingerPrint length");
}int sameCount = 0;for (int i = 0; i < f1.length; ++i) {
{if (f1[i] ==f2[i]) {++sameCount;
}
}
}return (float) sameCount /f1.length;
}public static float compareCompact(byte[] f1, byte[] f2) {returncompare(uncompact(f1), uncompact(f2));
}public static floatcompare(BufferedImage image1, BufferedImage image2) {return new FingerPrint(image1).compare(newFingerPrint(image2));
}/***@paramargs
*@returnvoid
*@authorGuoyh
* @date /10/12 15:07*/
public static void main(String[] args) throwsException {for (int i = 18; i <= 21; i++) {
FingerPrint fp1= new FingerPrint(ImageIO.read(new File("G:/oss/pk/" + 18 + ".jpg")));
FingerPrint fp2= new FingerPrint(ImageIO.read(new File("G:/oss/pk/" + i + ".jpg")));
System.out.println("\t" + "\t"+"G:/oss/pk/" + 18 + ".jpg"+"\t"+"与"+"\t"+"G:/oss/pk/" + i + ".jpg"+"\t"+"两张图片的相似度为：" + pare(fp2) * 100 + "%");
}
}
}
