16Video and audio streams

RTP+RTSP

This method (actually RTP over UDP and RTSP over TCP) should be your first consideration for live video, especially when it is important to always have an up-to-date video stream, even if some images get dropped. This can be configured as multicast or unicast.

Multicasting provides the most efficient usage of bandwidth, especially when there are large numbers of clients viewing simultaneously. Note however, that a multicast broadcast cannot pass a network router unless the router is configured to allow this. It is thus not possible to multicast over the Internet for example.

Unicasting should be used for video-on-demand broadcasting, so that there is no video traffic on the network until a client connects and requests the stream. However, if more and more unicast clients connect, the server will at some point become overloaded. There is also the maximum of 20 simultaneous viewers to be considered.

RTP/RTSP

This unicast method is RTP tunneled over RTSP. This can be used to exploit the fact that it is relatively simple to configure firewalls to allow RTSP traffic.

RTP/RTSP/HTTP or RTP/RTSP/HTTPS

These two methods can also be used to traverse firewalls. Firewalls are commonly configured to allow the HTTP protocol, thus allowing RTP to be tunneled.

Other methods of accessing the video stream

Video/images from the Axis video server can also be accessed in the following ways:

If supported by the client, the Axis video server can use Motion JPEG server push to display video. This option maintains an open HTTP connection to the web browser and sends data as and when required, for as long as required.

As single JPEG images in a browser. Enter the path, for example: http://<ip>/axis-cgi/jpg/image.cgi?resolution=CIF

Windows Media Player. This requires AMC and the MPEG-4 decoder to be installed. The paths that can be used are listed below, in the order of preference.

Unicast via RTP: axrtpu://<ip>/mpeg4/media.amp

Unicast via RTSP: axrtsp://<ip>/mpeg4/media.amp

Unicast via RTSP, tunneled via HTTP: axrtsphttp://<ip>/mpeg4/media.amp

Unicast via RTSP, tunneled via HTTPS: axrtsphttps://<ip>/mpeg4/media.amp

Multicast: axrtpm://<ip>/mpeg4/media.amp

Notes: <ip> = IP address.

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Axis Communications 243SA user manual Other methods of accessing the video stream, RTP/RTSP/HTTP or RTP/RTSP/HTTPS