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Streamer for the elphel353 v8.0.4

The streamer is a standard RTSP streamer and supports unicast or multicast streaming of video with audio.

Watching a unicast video stream from the streamer

The camera will automatically be setup for unicast streams by default. With Mplayer all you need to do is use the following command:

mplayer rtsp://192.168.0.1:554

This will start broadcasting the video stream to your computer.

Enabling and watching multicast video stream from the streamer

Sometimes you need to have more than one computer viewing the stream. In order to do this you have to enable multicast. In unicast mode the camera only broadcasts the video if there is a client connection. Enabling multicast will mean that it is broadcasting all of the time and is not initiated by a client request. In order to enable the multicast option in version 8.0.4 you can't use the camera control interface. Instead use the Parameter Editor. Select the Streamer checkbox and click on View/Edit Current. This will open a new window/tab and you should see the option STROP_MCAST_EN. Change the value to 1, verify the apply box is checked and then click the Apply button. The camera is now in multicast mode and is always broadcasting the video. Multicast is a scheme for using ip addresses 224.0.0.0 through 239.255.255.255 to send the same data to several machines simultaneously. Addresses between 224.0.0.0 and 224.0.0.255 are reserved for maintenance protocols and aren't forwarded off your subnet. To receive multicast packets on linux host do next(by root):

route add -net 224.0.0.0 netmask 240.0.0.0 dev eth0
ping -t 1 -c 2 224.0.0.1 

should show up your local multicast-capable hosts. With Mplayer you can use the same command to enable the viewing of the stream:

mplayer rtsp://192.168.0.1:554

This will download a SDP file from the camera which will tell the computer where it can connect to view the multicast stream.

Adding audio to the Streamer (in version 8.0.4 using mplayer has issues with syncing audio with the video and does not work in multicast mode once the second client connects)

If you want to add audio to your stream you just have to use a usb audio device that is compatible with the alsa drivers. Connect the USB audio device to the usb port and connect your mic. You can only enable audio in the stream by using the parameter editor select the Streamer checkbox and click on View/Edit Current. This will open a new window/tab and you should see the option STROP_AUDIO_EN. Change the value to 1, verify the apply box is checked and then click the Apply button.