Creatting配備Retina支持一個BufferedImage

Question

我用我的development.When我創建了一個簡單的servlet，其用於生成驗證碼最新的JDK 7u45，我發現圖像是相當blurred.The圖像看起來就像這樣：

的圖像質量是比較差的，而且看起來真的很差，我的MacBook Pro的Retina顯示屏。 我使用創建的BufferedImage的代碼很簡單：

public static BufferedImage getImage() { 
     BufferedImage image = new BufferedImage(IMAGE_WIDTH,IMAGE_HEIGHT,BufferedImage.TYPE_INT_RGB); 
     Graphics graphics = image.getGraphics(); 
     drawRandomNumber((Graphics2D)graphics); 

     return image; 
    } 

    private static void drawRandomNumber(Graphics2D graphics) { 
     graphics.setColor(Color.RED); 
     graphics.setFont(new Font("Arial",Font.BOLD|Font.ITALIC,RANDOM_NUMBER_FONT_SIZE)); 
     char lch = 'a',hch = 'z'; 
     char lcach = 'A',hcach = 'Z'; 
     int x = RANDOM_NUMBER_START_X; 
     for (int i = 0;i < RANDOM_NUMBER_NUM;i++) { 
      char ch = new Random().nextBoolean() ? 
        (char)(new Random().nextInt(hch - lch) + lch) : 
        (char)(new Random().nextInt(hcach - lcach) + lcach); 

      int degree = new Random().nextInt() % 30; 
      graphics.rotate(degree * Math.PI/180,x,RANDOM_NUMBER_START_Y); 
      graphics.drawString(ch + "",x,RANDOM_NUMBER_START_Y); 
      graphics.rotate(-degree * Math.PI/180,x,RANDOM_NUMBER_START_Y); 
      x += 60; 
     } 
    } 

而且該圖像寫入到servlet代碼：

ImageIO.write(image, "png", response.getOutputStream()); 

我只是想知道如果我想創建一個支持HDPI顯示的高質量圖像，我該怎麼辦？有沒有什麼方法可以用java代碼生成高質量的圖像？我嘗試了很多方法，但它們似乎毫無幫助。

Answer 1

private float xScaleFactor, yScaleFactor = ...; 
    private BufferedImage originalImage = ...; 

    public void paintComponent(Graphics g) { 
     Graphics2D g2 = (Graphics2D)g; 
     int newW = (int)(originalImage.getWidth() * xScaleFactor); 
     int newH = (int)(originalImage.getHeight() * yScaleFactor); 
     g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION, 
          RenderingHints.VALUE_INTERPOLATION_BILINEAR); 
     g2.drawImage(originalImage, 0, 0, newW, newH, null); 
    }