Question

我在java代码中有很少的类和函数。其中一个功能是使用图形对象绘制图形。我想以jpg格式保存此图，所以我做了：

public void paintComponent(Graphics graphics) {
Graphics g1=null;
double scale = ((double) ySize) / histogram.getMaxFrequency(band);
if (histColor != null)
  graphics.setColor(histColor);
for (int x = 0; x < 256; ++x) {
  int y = (int) Math.round(scale*histogram.getFrequency(band, x));
  if (y > 0)
    graphics.drawLine(x+xOrigin, yOrigin, x+xOrigin, yOrigin-y);
}
FileOutputStream fileopstream;
try {
    fileopstream = new FileOutputStream("C:\\Users\\spider\\Desktop\\Study\\Computer Vision\\programs\\histogram1.jpg");
JPEGImageEncoder output=JPEGCodec.createJPEGEncoder(fileopstream);  
BufferedImage image= new BufferedImage(100,100,BufferedImage.TYPE_BYTE_BINARY);
//WritableRaster raster=image.getRaster();
g1=image.createGraphics();
g1=graphics.create();
//g1.dispose();
//graphics.drawImage(image, 0, 0, 100, 100, null, null);
//output.encode(image);
// Save as JPEG
File file = new File("newimage.jpg");
ImageIO.write(image, "jpg", file);
} catch (FileNotFoundException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} catch (ImageFormatException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}
drawAxis(graphics, xOrigin, yOrigin+1);

}

但它不起作用。存储的图像是空白图像，而不是我在屏幕上可以看到的图形。你能帮我吗

非常感谢

Answer 1

得到了答案:) 检查： http://www.exampledepot.com/egs/javax.imageio/Graphic2File.html#comment-83262

将图形保存到缓冲图像

1 个答案: