java - 旋转 bufferedImage 会改变图像的大小

Question

我正在尝试将 bufferedImage 旋转 90°，但我无法完全完成。

我可以旋转图像，但生成的图像有点奇怪。

1) 左右两侧黑边

2)信息丢失

举个例子:

这是原始图像。

旋转图像后，我得到了这个:

我真的不知道我在这里做错了什么。

这是我用来旋转缓冲图像的代码:

BufferedImage imgIn = ImageIO.read(new File("landscape.jpg"));
BufferedImage imgIn2 = imgIn;
        AffineTransform tx = new AffineTransform();
        tx.rotate(Math.PI / 2, imgIn2.getWidth() / 2, imgIn2.getHeight() / 2);//(radian,arbit_X,arbit_Y)
        AffineTransformOp op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
        BufferedImage rotatedImage = new BufferedImage(imgIn2.getHeight(), imgIn2.getWidth(), imgIn2.getType());
        op.filter(imgIn2, rotatedImage);
        ImageIO.write(rotatedImage, "JPEG", new File("testRotation.jpg"));

帮助将不胜感激!

Answer 1

使用仿射变换

import javax.imageio.ImageIO;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.File;

public class test {
    public static void main(String[] arg)throws Exception
    {
        BufferedImage imgIn = ImageIO.read(new File("/home/arpit/Desktop/image.jpg"));
        BufferedImage imgIn2 =  new BufferedImage(imgIn.getHeight(), imgIn.getWidth(), imgIn.getType());

        AffineTransform tx = new AffineTransform();
        tx.rotate(Math.PI / 2, imgIn2.getWidth() / 2, imgIn.getHeight() / 2);
        AffineTransformOp op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
        op.filter(imgIn, imgIn2);

        ImageIO.write(imgIn2, "JPEG", new File("/home/arpit/Desktop/testrotated.jpg"));
    }
}

没有仿射变换

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;

public class test {
    public static void main(String[] arg)throws Exception
    {
        BufferedImage imgIn = ImageIO.read(new File("/home/arpit/Desktop/image.jpg"));
        BufferedImage imgIn2 =  new BufferedImage(imgIn.getHeight(), imgIn.getWidth(), imgIn.getType());

        for(int x=0;x<imgIn.getWidth();x++)
        {
            for(int y=0;y<imgIn.getHeight();y++)
            {
                int color = imgIn.getRGB(x,y);
                imgIn2.setRGB(imgIn2.getWidth()-1-y,x,color);

            }
        }
        ImageIO.write(imgIn2, "JPEG", new File("/home/arpit/Desktop/testrotated.jpg"));
    }
}