JavaCV获取视频文件时长的方法

package com.duoduo.javacv.samples;import static com.googlecode.javacv.cpp.opencv_highgui.CV_CAP_PROP_FPS;import static com.googlecode.javacv.cpp.opencv_highgui.CV_CAP_PROP_FRAME_COUNT;import static com.googlecode.javacv.cpp.opencv_highgui.cvCreateFileCapture;import static com.googlecode.javacv.cpp.opencv_highgui.cvGetCaptureProperty;import static com.googlecode.javacv.cpp.opencv_highgui.cvReleaseCapture;import java.io.File;import com.googlecode.javacv.cpp.opencv_highgui.CvCapture;/** * 获取视频时长 *  * @author chengesheng * @date 2013-5-22 下午11:15:25 * @note VideoFileLength */public final class VideoFileLength { public static void main(String[] argus) { float len = getVideoFileLength("D:/J2EE/kdvp/webrtc/webapp/images/bike.avi"); System.out.println("Video length: " + len + " s"); } public static float getVideoFileLength(String fileName) { File file = new File(fileName); if (!file.exists()) {  return 0; } float len = 0; CvCapture capture = cvCreateFileCapture(fileName); try {  // 获取视频总帧数  long frameCount =(long) cvGetCaptureProperty(capture, CV_CAP_PROP_FRAME_COUNT);  // 获取视频每秒帧数  long fps =(long) cvGetCaptureProperty(capture, CV_CAP_PROP_FPS);  len = (float) frameCount / fps; } catch (Exception e) {  e.printStackTrace(); } finally {  cvReleaseCapture(capture); } return len; }}