Java：JMF 從player截圖

package implementation;

import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;


import javax.media.Buffer;
import javax.media.Player;
import javax.media.control.FrameGrabbingControl;
import javax.media.format.VideoFormat;
import javax.media.util.BufferToImage;

import com.sun.image.codec.jpeg.ImageFormatException;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

public class PhotoCatch {
	private Buffer buffer;
	private BufferToImage bufferToImage;
	private Image image;
	private FrameGrabbingControl fgc;
	
	public PhotoCatch(Player player){
		fgc = (FrameGrabbingControl) player.getControl("javax.media.control.FrameGrabbingControl");
		this.buffer = fgc.grabFrame();
		bufferToImage = new BufferToImage((VideoFormat) buffer.getFormat());
		image = bufferToImage.createImage(this.buffer);
	}
	public void upDate(){
		this.buffer = fgc.grabFrame();
		bufferToImage = new BufferToImage((VideoFormat) buffer.getFormat());
		image = bufferToImage.createImage(this.buffer);
	}
	public int getImageWidth(){
		return image.getWidth(null);
	}
	public int getImageHeight(){
		return image.getHeight(null);
	}
	public void saveImage(String address){
		saveImage(image,address);
	}
	
	private void saveImage(Image image, String path) {
		if(this.image == null)
			System.out.println("image is null");
		BufferedImage bi = new BufferedImage(image.getWidth(null), image.getHeight(null), BufferedImage.TYPE_INT_RGB);
		Graphics2D g2 = bi.createGraphics();
		g2.drawImage(image, null, null);
		FileOutputStream fos = null;

		try {

			fos = new FileOutputStream(path);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		JPEGImageEncoder je = JPEGCodec.createJPEGEncoder(fos);
		JPEGEncodeParam jp = je.getDefaultJPEGEncodeParam(bi);
		jp.setQuality(0.5f, false);
		je.setJPEGEncodeParam(jp);
		try {
			je.encode(bi);
			fos.close();
		} catch (ImageFormatException e) {
			// TODO Auto-generated catch block
			System.out.println("錯誤4");
		} catch (IOException e) {
			// TODO Auto-generated catch block
			//e.printStackTrace();
			System.out.println("錯誤5");
		}
	}
}

每次需要重新截圖時候，一定要進行更新！因爲JMF API 中

Class BufferToImage

This is a utility class to convert a video Buffer object to an AWTImage object that you can then render using AWT methods.

You can use this class in conjunction with the FrameGrabbingControl to grab frames from the video renderer and manipulate the image. 

bufferToImage是共用的，如果不進行更新的話。buffer會失效，導致無法轉換爲image，也就無法成功截圖了！