Using Mplayer With Video API

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Video API allow to obtain the video stream by HTTP and RTP/UDP. In difference from the Axis cameras, the Elphel cameras can obtain the MJPG stream or Theora stream by the RTP protocol.

HTTP

It's example of command for MPJPG format stream obtaining from camera (Elphel, Axis etc):

$mplayer -fps 6 -demuxer lavf http://192.168.0.9/mjpg/video.mjpg

If you want to obtain the stream with the non-specify parameters, the small trick is necessary. In fact, the lavf obtain the stream as MPJPG when the file name or URL have extension ".mjpg" at the end. Therefore to URL it is necessary to add the fictitious parameter with extension ".mjpg", for example:

$mplayer -fps 6 -demuxer lavf http://192.168.0.9/axis-cgi/mjpg/video.cgi?resolution=1024x768&bogus.mjpg

Also MPlayer can play the files which is the recorded MJPG stream. For example, the stream was saved by this way:

$wget http://192.16.0.9/axis-cgi/mjpg/video.cgi?resolution=1024x768 -O video.mjpg

with fps value 6, you can play this file by the next way:

$mplayer -fps 6 -demuxer lavf video.mjpg

RTP

MJPG

Multicast

In standard Axis Video API there is no possibility for obtaining multicast stream by RTSP. But there is possibility for SDP-file obtaining and obtain stream on the SDP base.

You can obtain the SDP-file from address:

http://192.168.0.9/mjpg/media.sdp

After that you can play stream:

$mplayer sdp://media.sdp

or save into the file:

$mencoder -fps 2 sdp://media.sdp -ovc copy -o my.avi 

Unfortunately, you must specify the fps for correctness of mencoder work, although in sdp-file this parameter is present.

Unicast

It is possible to address to camera's RTSP-server by using the RTSP-protocol and obtain the unicast video stream.

Theora