import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.File;
public class ThumbnailGenerator {
public void transform(String originalFile, String thumbnailFile,
int thumbWidth,
int thumbHeight,
int quality)
throws Exception
{
Image image = javax.imageio.ImageIO.read(
new File(originalFile));
double thumbRatio = (
double)thumbWidth / (
double)thumbHeight;
int imageWidth = image.getWidth(
null);
int imageHeight = image.getHeight(
null);
double imageRatio = (
double)imageWidth / (
double)imageHeight;
if (thumbRatio < imageRatio)
{
thumbHeight = (
int)(thumbWidth / imageRatio);
}
else
{
thumbWidth = (
int)(thumbHeight * imageRatio);
}
if(imageWidth < thumbWidth && imageHeight < thumbHeight)
{
thumbWidth = imageWidth;
thumbHeight = imageHeight;
}
else if(imageWidth < thumbWidth)
thumbWidth = imageWidth;
else if(imageHeight < thumbHeight)
thumbHeight = imageHeight;
BufferedImage thumbImage =
new BufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_RGB);
Graphics2D graphics2D = thumbImage.createGraphics();
graphics2D.setBackground(Color.WHITE);
graphics2D.setPaint(Color.WHITE);
graphics2D.fillRect(
0,
0, thumbWidth, thumbHeight);
graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
graphics2D.drawImage(image,
0,
0, thumbWidth, thumbHeight,
null);
javax.imageio.ImageIO.write(thumbImage,
"JPG",
new File(thumbnailFile));
}
}
转载于:https://www.cnblogs.com/bilaisheng/p/10210968.html
相关资源：java生成图片缩略图和二进制文件的工具类
