Problems taking MPEG4 multicast snapshots

[dhirwinjr]

All,

I'm trying to use VLC as part of a video snapshot tool but am experiencing problems with VLC snapshots. In particular, I'm experiencing problems when trying to take a snapshot of MPEG4 multicast video from an Optelecom hardware encoder. I use an SDP file to define each video stream/connection information. The problem is that VLC will occasionally save the wrong snapshot image to a file.

For example, here's a typically setup:

Code: Select all

new cam172_30_28_33 broadcast loop enabled setup cam172_30_28_33 input etc/camera_configs/cam172_30_28_33.sdp setup cam172_30_28_33 option vout=image setup cam172_30_28_33 option image-out-format=jpeg setup cam172_30_28_33 option image-out-prefix=/home/vlc/snapshots/cam172_30_28_33 setup cam172_30_28_33 option image-out-ratio=150 setup cam172_30_28_33 option image-out-replace new cam172_30_28_36 broadcast loop enabled setup cam172_30_28_36 input etc/camera_configs/cam172_30_28_36.sdp setup cam172_30_28_36 option vout=image setup cam172_30_28_36 option image-out-format=jpeg setup cam172_30_28_36 option image-out-prefix=/home/vlc/snapshots/cam172_30_28_36 setup cam172_30_28_36 option image-out-ratio=150 setup cam172_30_28_36 option image-out-replace

I then have a loop in my application, that communicates to VLC via telnet, that starts one camera, then stops it, then starts the other, stops the other, and continues in this loop forever. VLC will occasionally save the snapshot from the 172.30.28.33 encoder as cam172_30_28_36.jpeg. I've read through the SDP specification and they should be correct.

My application (written in Java) runs on Debian and connects to VLC 0.8.6a.

Anyone else have similar experiences or suggestions?

Thanks,
Dave

[dhirwinjr]

Eventually I found that this was a VLC running on Linux problem because when I run VLC on Windows XP I don't have this issue. I'm no Linux expert so I didn't attempt to find the exact issue on Linux but I can tell you it wasn't confined to a single Linux distribution (I tried both Fedora and Ubuntu before moving to Windows).

Thanks,
Dave