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Slowing the FPS down!

Posted: 18 Jun 2009 16:44
by k2skaterii
I am using VLC player to view a MPEG2 video which is being broadcast from another machine on my network. The MPEG2 is being generated from a program called VRSG (Virtual Reality Scene Generator) made by a company called METAVR. According to the VRSG documentation the MPEG2 is being sent out over a UDP stream, at 30 FPs.

I am able to direct VLC player to the stream where it will cache a few seconds of video, but then it will stop. If i give it a couple of seconds and move the slider bar i can get the video to start playing again, but i can see that the time stamp is counting up way too fast. Once the video on VLC hits the same time stamp as VRSG the video stops.

I believe that the VLC player is playing the video at 35 or 40 FPS, not 30 FPS. Does anyone know how i can force VLC player to play the UDP stream at 30 FPS?

Thanks in advance!

Re: Slowing the FPS down!

Posted: 19 Jun 2009 03:19
by The DJ
The source just needs to use proper dts, pts and pcr. This report screams incorrect timestamps.

Re: Slowing the FPS down!

Posted: 19 Jun 2009 17:32
by k2skaterii
thanks for pointing out the timing issue... I cant control the encoding speed... But that information was all i needed to locate my problem.

For some reason over the course of a minute the program is only encoding 37 seconds worth of video. So i am thinking that my 10 cache is filling up, then it starts playing the video at 30 FPS... But because the cache is not filling back up at 30 FPS, it is depleting the cache faster than it is being filled up. Then when there is finally no data left in the cache the video dies.

that also explains why the video seems to play "fast" it is playing @30 FPS, but there are only 20-24 frames available for each second of video.

Yea, so i just Emailed the company tech support and told them that the problem is in their software.

Fun times!
Thanks again