Javacv: FFmpegFrameGrabber.getLengthInTime() is 0

[chenhl05]

Hello, I can't get the duration time of video file.
I use VideoInputFrameGrabber open webcam.
The FFmpegFrameRecorder also call setTimestamp() function.
But FFmpegFrameGrabber.getLengthInTime() can't get duration of video file , which FFmpegFrameRecorder generating.
Could you help me ?

[saudet]

Not all video files come with that information, that's normal. To have
FFmpegFrameRecorder write that information, you'll need to call stop().

[MayZhou]

Not all video files come with that information, that's normal. To have FFmpegFrameRecorder write that information, you'll need to call stop().

can I use close() for the same purpose?

[saudet]

Yes, it calls stop():
https://github.com/bytedeco/javacv/blob/master/src/main/java/org/bytedeco/javacv/FrameRecorder.java#L398

[chenhl05]

Thanks, it took effect after I changed my code.