BufferedImage与Image

1、BufferedImage类型与Byte[]流之间相互转化

1.须要用到的类

java.awt.image.BufferedImage;

javax.imageio.ImageIO;

java.io.*;

2.为何要将BufferedImage转为byte数组

    在传输中，图片是不能直接传的，所以须要把图片变为字节数组，而后传输比较方便；只须要通常输出流的write方法便可；而字节数组变成BufferedImage可以还原图像；

3.如何取得BufferedImage

BufferedImage image = ImageIO.read(new File("1.gif"));

4.BufferedImage ------>byte[]

ImageIO.write(BufferedImage image,String format,OutputStream out);方法能够很好的解决问题；

参数image表示得到的BufferedImage；

参数format表示图片的格式，好比“gif”等；

参数out表示输出流，若是要转成Byte数组，则输出流为ByteArrayOutputStream便可；

执行完后，只须要toByteArray()就能获得byte[];

5.byte[] ------>BufferedImage

ByteArrayInputStream in = new ByteArrayInputStream(byte[]b); //将b做为输入流；
BufferedImage image = ImageIO.read(InputStream in); //将in做为输入流，读取图片存入image中，而这里in能够为ByteArrayInputStream();

6.显示BufferedImage

public void paint(Graphics g){

    super.paint(g);

    g.drawImage(image);    //image为BufferedImage类型

}

2、BufferedImage与Image之间的相互转换

1.

BufferedImage input = ImageIO.read(file1);

Image big = input.getScaledInstance(256, 256,Image.SCALE_DEFAULT); //放缩图片

BufferedImage inputbig = new BufferedImage(256, 256,BufferedImage.TYPE_INT_BGR);
inputbig.getGraphics().drawImage(input, 0, 0, 256, 256, null); //画图

2.

public BufferedImage toBufferedImage(Image image) {
if (image instanceof BufferedImage) { return (BufferedImage) image; }

image = new ImageIcon(image).getImage(); 

//ImageIcon与Image之间的转化: ImageIcon icon = new ImageIcon(image); image = icon.getImage();

boolean hasAlpha = false;

BufferedImage bimage = null;

GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();

try {

int transparency = Transparency.OPAQUE;

if (hasAlpha) { transparency = Transparency.BITMASK; }

GraphicsDevice gs = ge.getDefaultScreenDevice();

GraphicsConfiguration gc = gs.getDefaultConfiguration();

bimage = gc.createCompatibleImage(image.getWidth(null),

image.getHeight(null), transparency);

} catch (HeadlessException e) {

}

if (bimage == null) {

int type = BufferedImage.TYPE_INT_RGB;

if (hasAlpha) { type = BufferedImage.TYPE_INT_ARGB; }

bimage = new BufferedImage(image.getWidth(null),image.getHeight(null), type);

}

Graphics g = bimage.createGraphics();

g.drawImage(image, 0, 0, null);

g.dispose();

return bimage;

}