java照片处理

Question

BufferedImage bin=ImageIO.read(new File("g:/1.jpg"));
    
     ImageIO.write(bin,"jpg",new File("g:/2.jpg"));
为什么图片会变小呢？怎么样能保持图片大小不变

Answer 1

BufferedImage src = ImageIO.read(url);
int width = src.getWidth(null);
int height = src.getHeight(null);
//这里BufferedImage.TYPE_BYTE_GRAY根据你自己的图片来定
BufferedImage outImg = new BufferedImage(width, height,BufferedImage.TYPE_BYTE_GRAY);
outImg.getGraphics().drawImage(src, 0, 0, width, height, null);
FileOutputStream out = new FileOutputStream(localPath);
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
encoder.encode(outImg);
out.close();

Answer 2

没有变小啊。借鉴楼主的：
import javax.imageio.*;
import java.awt.image.*;
public class ImageHandle{
public static void main(String[]args)throws Exception{
BufferedImage bin=ImageIO.read(new File("c:\\1.jpg"));
System.out.println("heigth1: "+bin.getHeight());
System.out.println("width1: "+bin.getWidth());
ImageIO.write(bin,"jpg",new File("c:\\2.jpg"));
bin=ImageIO.read(new File("c:\\2.jpg"));
System.out.println("heigth2: "+bin.getHeight());
System.out.println("width2: "+bin.getWidth());
}
}输出：
heigth1: 570
width1: 760
heigth2: 570
width2: 760