Java - 在不损失质量的情况下调整图像大小视觉比较兰佐斯重采样渐进式扩展关于JDK扩展方法的一句话
2022-08-31 14:28:49
我有10，000张照片需要调整大小，所以我有一个Java程序来做到这一点。不幸的是，图像的质量丢失得很差，我无法访问未压缩的图像。
import java.awt.Graphics;
import java.awt.AlphaComposite;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
/**
* This class will resize all the images in a given folder
* @author
*
*/
public class JavaImageResizer {
public static void main(String[] args) throws IOException {
File folder = new File("/Users/me/Desktop/images/");
File[] listOfFiles = folder.listFiles();
System.out.println("Total No of Files:"+listOfFiles.length);
BufferedImage img = null;
BufferedImage tempPNG = null;
BufferedImage tempJPG = null;
File newFilePNG = null;
File newFileJPG = null;
for (int i = 0; i < listOfFiles.length; i++) {
if (listOfFiles[i].isFile()) {
System.out.println("File " + listOfFiles[i].getName());
img = ImageIO.read(new File("/Users/me/Desktop/images/"+listOfFiles[i].getName()));
tempJPG = resizeImage(img, img.getWidth(), img.getHeight());
newFileJPG = new File("/Users/me/Desktop/images/"+listOfFiles[i].getName()+"_New");
ImageIO.write(tempJPG, "jpg", newFileJPG);
}
}
System.out.println("DONE");
}
/**
* This function resize the image file and returns the BufferedImage object that can be saved to file system.
*/
public static BufferedImage resizeImage(final Image image, int width, int height) {
int targetw = 0;
int targeth = 75;
if (width > height)targetw = 112;
else targetw = 50;
do {
if (width > targetw) {
width /= 2;
if (width < targetw) width = targetw;
}
if (height > targeth) {
height /= 2;
if (height < targeth) height = targeth;
}
} while (width != targetw || height != targeth);
final BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
final Graphics2D graphics2D = bufferedImage.createGraphics();
graphics2D.setComposite(AlphaComposite.Src);
graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION,RenderingHints.VALUE_INTERPOLATION_BILINEAR);
graphics2D.setRenderingHint(RenderingHints.KEY_RENDERING,RenderingHints.VALUE_RENDER_QUALITY);
graphics2D.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
graphics2D.drawImage(image, 0, 0, width, height, null);
graphics2D.dispose();
return bufferedImage;
}
我正在处理的图像是这样的：
这是我在Microsoft Paint中完成的手动调整大小：
这是我的程序[双线性]的输出：
更新：使用无显著差异BICUBIC
这是我的程序[双三次]的输出：
是否无论如何都可以提高程序输出的质量，这样我就不必手动调整所有照片的大小？
提前感谢您！
