javacv视频截图

package com.repast.core.tool;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
 
import javax.imageio.ImageIO;
 
import org.bytedeco.javacpp.opencv_core;
import org.bytedeco.javacpp.opencv_core.IplImage;
import org.bytedeco.javacv.FFmpegFrameGrabber;
import org.bytedeco.javacv.Frame;
import org.bytedeco.javacv.FrameGrabber.Exception;
import org.bytedeco.javacv.Java2DFrameConverter;
import org.bytedeco.javacv.OpenCVFrameConverter;
 /**
  * javacv 
  * @author 周海峰
  *
  */
public  class FrameGrabberKit {
    public static void main(String[] args) throws Exception {
    	System.out.println(System.getProperty("java.library.path"));
    	try {
			fetchFrame("D:/video/aa.mp4", "D:/new/aa.jpg");
		} catch (IOException e) {
			e.printStackTrace();
		}
    }
 
    /**
     * 获取指定视频的帧并保存为图片至指定目录
     * @param videofile  源视频文件路径
     * @param framefile  截取帧的图片存放路径
     * @throws Exception
     * @throws IOException 
     */
    public static void fetchFrame(String videofile, String framefile)
            throws Exception, IOException {
        FFmpegFrameGrabber ff = new FFmpegFrameGrabber(videofile); 
        ff.start();
        ff.getAudioChannels();
        String rotate =ff.getVideoMetadata("rotate");//视频的旋转角度
        int lenght = ff.getLengthInFrames();
        int i = 0;
        Frame f = null;
        while (i < lenght) {
            // 过滤前5帧，避免出现全黑的图片，依自己情况而定
            f = ff.grabFrame();
            if ((i > 5) && (f.image != null)) {
            	break;
            }
            IplImage src = null;
                if(null !=rotate &&rotate.length() > 1) {
                    OpenCVFrameConverter.ToIplImage converter =new OpenCVFrameConverter.ToIplImage();
                        src =converter.convert(f);
                        f =converter.convert(rotate(src, Integer.valueOf(rotate)));
                    }
                doExecuteFrame(f, framefile);
            i++;
        }
        
    }
    
    
    public static IplImage rotate(IplImage src,int angle) {
        IplImage img = IplImage.create(src.height(),src.width(),src.depth(),src.nChannels());
        opencv_core.cvTranspose(src,img);
        opencv_core.cvFlip(img,img,angle);
        return img;
    }
    
    
    public static void doExecuteFrame(Frame f,String targetFileName) {
        if (null ==f ||null ==f.image) {
            return;
        }
        Java2DFrameConverter converter =new Java2DFrameConverter();
        BufferedImage bi =converter.getBufferedImage(f);
        File output =new File(targetFileName);
        try {
            ImageIO.write(bi,"jpg",output);
        }catch (IOException e) {
            e.printStackTrace();
        }
    }
 
}

            org.bytedeco
            javacv-platform
            1.3.1