利用直方圖原理實現圖像內容相似度比較 ，作為筆記記錄在隨筆中。
public
class
PhotoDigest {
public
static
void
main(String[] args)
throws
Exception {
float
percent = compare(getData(
"/Users/sun/Downloads/1.jpg"
),
getData(
"/Users/sun/Downloads/2.jpg"
));
if
(percent ==
0
) {
System.out.println(
"無法比較"
);
}
else
{
System.out.println(
"兩張圖片的相似度為："
+ percent +
"%"
);
}
}
public
static
int
[] getData(String name) {
try
{
BufferedImage img = ImageIO.read(
new
File(name));
BufferedImage slt =
new
BufferedImage(
100
,
100
,
BufferedImage.TYPE_INT_RGB);
slt.getGraphics().drawImage(img,
0
,
0
,
100
,
100
,
null
);
// ImageIO.write(slt,"jpeg",new File("slt.jpg"));
int
[] data =
new
int
[
256
];
for
(
int
x =
0
; x < slt.getWidth(); x++) {
for
(
int
y =
0
; y < slt.getHeight(); y++) {
int
rgb = slt.getRGB(x, y);
Color myColor =
new
Color(rgb);
int
r = myColor.getRed();
int
g = myColor.getGreen();
int
b = myColor.getBlue();
data[(r + g + b) /
3
]++;
}
}
// data 就是所謂圖形學當中的直方圖的概念
return
data;
}
catch
(Exception exception) {
System.out.println(
"有文件沒有找到,請檢查文件是否存在或路徑是否正確"
);
return
null
;
}
}
public
static
float
compare(
int
[] s,
int
[] t) {
try
{
float
result = 0F;
for
(
int
i =
0
; i <
256
; i++) {
int
abs = Math.abs(s[i] - t[i]);
int
max = Math.max(s[i], t[i]);
result += (
1
- ((
float
) abs / (max ==
0
?
1
: max)));
}
return
(result /
256
) *
100
;
}
catch
(Exception exception) {
return
0
;
}
}
}