美文网首页
Java ImageIO 图片处理后变红 解决办法记录

Java ImageIO 图片处理后变红 解决办法记录

作者: Zal哥哥 | 来源:发表于2021-06-19 14:47 被阅读0次

    原因:根据网上搜罗的一大堆文章以及自己的发现,是因为原始图片(jpeg)带有alpha通道才会变红,在mac上直接显示简介的看到。


    image.png

    然后发现使用下面这个方式可以解决变红的问题

    // 把这行换成下面的方式
    BufferedImage image = ImageIO.read(originFile);
    
    // 这里是直接根据url读取图片
    public static BufferedImage getBufferedImage(String  imgUrl) throws MalformedURLException {
        URL url = new URL(imgUrl);
        ImageIcon icon = new ImageIcon(url);
        Image image = icon.getImage();
        
        // 如果是从本地加载,就用这种方式,没亲自测试过
        // Image src=Toolkit.getDefaultToolkit().getImage(filePath);
    
        // This code ensures that all the pixels in the image are loaded
        BufferedImage bimage = null;
        GraphicsEnvironment ge = GraphicsEnvironment
                .getLocalGraphicsEnvironment();
        try {
            int transparency = Transparency.OPAQUE;
            GraphicsDevice gs = ge.getDefaultScreenDevice();
            GraphicsConfiguration gc = gs.getDefaultConfiguration();
            bimage = gc.createCompatibleImage(image.getWidth(null),
                    image.getHeight(null), transparency);
        } catch (HeadlessException e) {
            // The system does not have a screen
        }
        if (bimage == null) {
            // Create a buffered image using the default color model
            int type = BufferedImage.TYPE_INT_RGB;
            bimage = new BufferedImage(image.getWidth(null),
                    image.getHeight(null), type);
        }
        // Copy image to buffered image
        Graphics g = bimage.createGraphics();
        // Paint the image onto the buffered image
        g.drawImage(image, 0, 0, null);
        g.dispose();
        return bimage;
    }
    

    原文链接:https://blog.csdn.net/Wu_Shang001/article/details/108227611

    一个完整的例子:

    package cn.com.xxx.web.controller;
    
    import io.swagger.annotations.Api;
    import io.swagger.annotations.ApiOperation;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.ResponseBody;
    
    import javax.imageio.ImageIO;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.swing.*;
    import java.awt.*;
    import java.awt.image.BufferedImage;
    import java.io.IOException;
    import java.io.InputStream;
    import java.io.OutputStream;
    import java.net.MalformedURLException;
    import java.net.URL;
    
    @Controller
    @RequestMapping("/image")
    @Api(tags = "图片处理")
    public class ImageController {
    
        public static BufferedImage getBufferedImage(String  imgUrl) throws MalformedURLException {
            URL url = new URL(imgUrl);
            ImageIcon icon = new ImageIcon(url);
            Image image = icon.getImage();
    
            // 如果是从本地加载,就用这种方式,没亲自测试过
            // Image src=Toolkit.getDefaultToolkit().getImage(filePath);
    
            // This code ensures that all the pixels in the image are loaded
            BufferedImage bimage = null;
            GraphicsEnvironment ge = GraphicsEnvironment
                    .getLocalGraphicsEnvironment();
            try {
                int transparency = Transparency.OPAQUE;
                GraphicsDevice gs = ge.getDefaultScreenDevice();
                GraphicsConfiguration gc = gs.getDefaultConfiguration();
                bimage = gc.createCompatibleImage(image.getWidth(null),
                        image.getHeight(null), transparency);
            } catch (HeadlessException e) {
                // The system does not have a screen
            }
            if (bimage == null) {
                // Create a buffered image using the default color model
                int type = BufferedImage.TYPE_INT_RGB;
                bimage = new BufferedImage(image.getWidth(null),
                        image.getHeight(null), type);
            }
            // Copy image to buffered image
            Graphics g = bimage.createGraphics();
            // Paint the image onto the buffered image
            g.drawImage(image, 0, 0, null);
            g.dispose();
            return bimage;
        }
    
        /**
         * 获取远程网络图片信息
         * @param imageURL
         * @return
         */
        public BufferedImage getRemoteBufferedImage(String imageURL) {
            URL url = null;
            InputStream is = null;
            BufferedImage bufferedImage = null;
            try {
                url = new URL(imageURL);
                is = url.openStream();
                bufferedImage = ImageIO.read(is);
            } catch (MalformedURLException e) {
                e.printStackTrace();
                System.out.println("imageURL: " + imageURL + ",无效!");
                return null;
            } catch (IOException e) {
                e.printStackTrace();
                System.out.println("imageURL: " + imageURL + ",读取失败!");
                return null;
            } finally {
                try {
                    if (is!=null) {
                        is.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                    System.out.println("imageURL: " + imageURL + ",流关闭异常!");
                    return null;
                }
            }
            return bufferedImage;
        }
    
        public BufferedImage mergeImage(String file1Url, String file2Url) throws MalformedURLException {
            BufferedImage b = getBufferedImage(file1Url);
            BufferedImage d = getBufferedImage(file2Url);
    
            try {
                int w = d.getWidth() / 4; //b.getWidth();
                int h = d.getHeight() / 4; // b.getHeight();
                int x = d.getWidth() / 2 - w / 2;
                int y = d.getHeight() / 2 - h / 2;
    
                Graphics2D g = d.createGraphics();
                g.drawImage(b, x, y, w, h, null);
                g.dispose();
            } catch (Exception e) {
                System.out.println(e.getMessage());
            }
    
            return d;
        }
    
        /**
         * 根据url进行图片合并
         */
        @ResponseBody
        @RequestMapping(value = "mergeImage", method = RequestMethod.GET)
        @ApiOperation(value = "根据url进行图片合并", httpMethod = "GET")
        public void mergeImage(HttpServletRequest request, HttpServletResponse response) throws MalformedURLException {
            BufferedImage bufferedImage = mergeImage("https://static-oss.cs.kemai.com.cn/vshop/0/c02582c1bba440ae89c216a8e9701daa.png", "https://work-cs.cloud.kemai.cn/img/qr_code.884b6411.png");
    
            response.setContentType("image/png");
            try (OutputStream out = response.getOutputStream()) {
                //这里直接写入输出流
                ImageIO.write(bufferedImage, "JPEG", response.getOutputStream());
            } catch (Exception e) {
                System.out.println(e.getLocalizedMessage());
            }
        }
    
    }
    
    

    相关文章

      网友评论

          本文标题:Java ImageIO 图片处理后变红 解决办法记录

          本文链接:https://www.haomeiwen.com/subject/tqhstltx.html