java 图片角度调整旋转、并获得图片信息

public class Demo {

/**
* 调整图片角度
* make by dongxh 2017年11月1日下午3:51:08
* @param src
* @param angel
* @return
*/
public static BufferedImage rotate(Image src, int angel) {
int src_width = src.getWidth(null);
int src_height = src.getHeight(null);
// calculate the new image size
Rectangle rect_des = CalcRotatedSize(new Rectangle(new Dimension(
src_width, src_height)), angel);

BufferedImage res = null;
res = new BufferedImage(rect_des.width, rect_des.height,
BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = res.createGraphics();
// transform
g2.translate((rect_des.width - src_width) / 2,
(rect_des.height - src_height) / 2);
g2.rotate(Math.toRadians(angel), src_width / 2, src_height / 2);

g2.drawImage(src, null, null);
return res;
}

/**
* 计算旋转参数
* make by dongxh 2017年11月1日下午3:51:29
* @param src
* @param angel
* @return
*/
public static Rectangle CalcRotatedSize(Rectangle src, int angel) {
// if angel is greater than 90 degree, we need to do some conversion
if (angel >= 90) {
if(angel / 90 % 2 == 1){
int temp = src.height;
src.height = src.width;
src.width = temp;
}
angel = angel % 90;
}

double r = Math.sqrt(src.height * src.height + src.width * src.width) / 2;
double len = 2 * Math.sin(Math.toRadians(angel) / 2) * r;
double angel_alpha = (Math.PI - Math.toRadians(angel)) / 2;
double angel_dalta_width = Math.atan((double) src.height / src.width);
double angel_dalta_height = Math.atan((double) src.width / src.height);

int len_dalta_width = (int) (len * Math.cos(Math.PI - angel_alpha
- angel_dalta_width));
int len_dalta_height = (int) (len * Math.cos(Math.PI - angel_alpha
- angel_dalta_height));
int des_width = src.width + len_dalta_width * 2;
int des_height = src.height + len_dalta_height * 2;
return new Rectangle(new Dimension(des_width, des_height));
}

/**
* 获得图片调整角度
* make by dongxh 2017年11月1日下午3:40:20
* @param imgFile
* @return
*/
public static Integer getImgRotateAngle(String imgFile){
Integer angel = 0;
Metadata metadata = null;
try{
if(StringUtils.isBlank(imgFile))return angel;
File _img_file_ = new File(imgFile);
if(!_img_file_.exists())return angel;
metadata = JpegMetadataReader.readMetadata(_img_file_);
Directory directory = metadata.getDirectory(ExifDirectory.class);
if(directory != null && directory.containsTag(ExifDirectory.TAG_ORIENTATION)){
int orientation = directory.getInt(ExifDirectory.TAG_ORIENTATION);
// 原图片的方向信息
if(6 == orientation ){
//6旋转90
angel = 90;
}else if( 3 == orientation){
//3旋转180
angel = 180;
}else if( 8 == orientation){
//8旋转90
angel = 270;
}
}
}catch(Exception e){
e.printStackTrace();
}
return angel;
}

/**
* 调整图片角度
* make by dongxh 2017年11月1日下午4:31:20
* @param imgFile
*/
public static void rotateImage(String imgFile){
try {
if(StringUtils.isBlank(imgFile)){
File _img_file_ = new File(imgFile);
if(_img_file_.exists()){
Integer angel = getImgRotateAngle(imgFile);
if(angel==0)return;
BufferedImage src = ImageIO.read(_img_file_);
BufferedImage des = rotate(src, angel);
ImageIO.write(des,"jpg", _img_file_);
}
}
} catch (IOException e) {
e.printStackTrace();
}
}

public static void main(String[] args)throws Exception{
String fromPic = "d://88888//IMG_20171004_122718.jpg";
//rotateImage(file);

Integer angel = getImgRotateAngle(fromPic);
System.out.println(angel);
Thumbnails.of(fromPic)
.rotate(angel)
.scale(0.2f)
.outputFormat("jpg")
.outputQuality(0.2f)
.toFile(fromPic);

System.out.println("==End==");
}

}

获得图片使用metadata-extractor

<dependency>
<groupId>com.drewnoakes</groupId>
<artifactId>metadata-extractor</artifactId>
<version>2.4.0-beta-1</version>
</dependency>