Hi all, I'm using the live555MediaServer application to stream an mpeg2 ts to a VLC client on linux. I used the MPEG2TransportStreamIndexer app to create a .tsx file to go along with the .ts file.
Playing the stream at a normal scale of 1.0 works just fine, as does playing it in fast forward or fast reverse, using other settings in the scale header. The problem comes when I attempt to "seek" in the stream to a specific time, or attempt to use the --start-time option to VLC to start at a point other than the beginning. The VLC implementation of the start-time option results in a PLAY request being sent with "Range: npt=0.000-" followed almost immediately by a second PLAY request with "Range: npt=<new-time>-". In the test I am performing, I set --start-time=15 on the VLC command line. What happens is that although I see in the VLC output that the reply to the PLAY request is nearly instantaneous, nothing happens for about 15 seconds, and then the data starts to stream and play, although VLC throws away the first number of frames because they arrived "too late" (VLC prints "late picture skipped"). Putting VLC into debug mode shows that VLC does not print the "first packet for pid" message until the full 15 seconds has elapsed, and then the first picture is discarded for being slightly over 15 seconds late. Wireshark shows that after the reply to the PLAY request, very few RTP packets are sent and they are sent in a strange timing pattern: I get 2 RTP packets 3.4 seconds apart, then 2 RTP packets 2.1 seconds apart, then 2 packets 1.3 seconds apart, etc... the time between packets continues to decay until finally at around the full 15 seconds after the PLAY request the stream seems to kick back in in full force. If I seek further into the stream, then the delay goes up correspondingly (e.g. a seek of 30 seconds doesn't start playing the new location in the stream until 30 seconds later) I would have expected the server to simply re-seek in the source stream and then continue uninterrupted without the long delay... Is seeking of mpeg2 ts streams expected to work with live555MediaServer, or have I run into a known problem? I didn't see anything about this on the live.com web site. Thanks for any thoughts, --Brett _______________________________________________ live-devel mailing list live-devel@lists.live555.com http://lists.live555.com/mailman/listinfo/live-devel
