java 切图按比例切图

最新推荐文章于 2024-02-01 15:56:41 发布

flashdream8

最新推荐文章于 2024-02-01 15:56:41 发布

阅读量501

点赞数

CC 4.0 BY-SA版权

分类专栏： java 基础问题及解决方法文章标签： java

本文链接：https://blog.youkuaiyun.com/flashdream8/article/details/84272600

问题及解决方法同时被 2 个专栏收录

97 篇文章

订阅专栏

java 基础

39 篇文章

订阅专栏

本文详细介绍了使用Java进行图片缩放并保存的技术实现，包括URL读取、缓冲区操作及JPEG编码等关键步骤。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

java 切图

public boolean scaleImageFromUrl(String oldpath, String newpath, int wdith,
			int height) {
		try {
			URL url = null;
			url = new URL(oldpath);
			URLConnection connection;
			connection = url.openConnection();
			BufferedImage bi = ImageIO.read(connection.getInputStream());
			Image Itemp = bi.getScaledInstance(wdith, height,
					BufferedImage.SCALE_SMOOTH);
			BufferedImage thumbnail = new BufferedImage(wdith, height,
					BufferedImage.TYPE_INT_RGB);
			thumbnail.getGraphics().drawImage(Itemp, 0, 0, null);
			File newimg = new File(newpath);
			FileOutputStream out = new FileOutputStream(newimg);
			JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
			JPEGEncodeParam param = encoder
			.getDefaultJPEGEncodeParam(thumbnail);
			param.setQuality(1.0f, false);
			encoder.encode(thumbnail);
			out.close();
			bi.flush();
			bi = null;
			return true;
		} catch (IOException e) {
			return false;
		}
	}

public boolean scaleImageFromUrl(String oldpath, String newpath, int wdith) {
		try {
			int height=367;
			URL url = null;
			url = new URL(oldpath);
			URLConnection connection;
			connection = url.openConnection();
			BufferedImage bi = ImageIO.read(connection.getInputStream());
			if(bi.getWidth()<=550){
				wdith=bi.getWidth();
				height=bi.getHeight();
			}else{
				height=(int)Math.floor(wdith*bi.getHeight()/bi.getWidth());
			}
			Image Itemp = bi.getScaledInstance(wdith, height,
					BufferedImage.SCALE_SMOOTH);
			BufferedImage thumbnail = new BufferedImage(wdith, height,
					BufferedImage.TYPE_INT_RGB);
			thumbnail.getGraphics().drawImage(Itemp, 0, 0, null);
			File newimg = new File(newpath);
			FileOutputStream out = new FileOutputStream(newimg);
			JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
			JPEGEncodeParam param = encoder
			.getDefaultJPEGEncodeParam(thumbnail);
			param.setQuality(0.8f, false);
			encoder.encode(thumbnail);
			out.close();
			bi.flush();
			bi = null;
			return true;
		} catch (IOException e) {
			e.printStackTrace();
			return false;
		}
	}