Network Video

This media type is similar to Live Video, except that video is received via the network rather than using a capture card. It can be used with network-enabled video cameras and other devices, applications and services capable of sending video over the network. WATCHOUT supports standard streaming protocols such as RTP and RTSP and video encoding formats such as H.264 or MPEG-2.

The advantage of this media type is that it requires no additional hardware installed in the computer and that it adds new kinds of video sources. A possible disadvantage is the noticeable delay incurred by the network stream processing, making it unsuitable for on-camera speaker display (IMAG), or other applications calling for low latency.

Assuming that you have such a network streaming source available, it can be incorporated into your presentation by choosing “Add Network Video” on the Media menu. Specify a name for the source, such as the name of a network-attached camera.

The media type has basic support for audio in the network streams, note however that the audio may start playing before the video appears.

Stream
Choose whether the data is sent as a multicast or unicast stream. In general, unicast is preferred. Use multicast only if the video stream will be shown by multiple display computers simultaneously. Most cameras unicast over UDP. Alternatively, choose TCP if required by the camera.

URI
Enter the Uniform Resource Identifier of the stream’s source. The details here vary with the camera or application sending the stream, so you need to consult the device’s documentation. As an example, an AXIS network camera used the following URI (where the group of digits is the IP address assigned to the camera):

rtsp://192.168.0.178/axis-media/media.amp

Preview
Select “Live” to see the network video in the Stage window. Generally, use this setting only for initial testing purposes, or when using a multicast stream (see above). For final playback, you’re advised to use the “Thumbnail” preview mode.

Enable WATCHPAX Hardware Acceleration
Applies only when displaying certain formats, such as H.264, on WATCHPAX. May improve video playback performance when playing high resolution video. This checkbox has no effect when using other display computers.

Apply Frame Blending
This setting often results in smoother video playback, at the possible expense of some loss in image sharpness. This is especially true when the frame-rate of the video is not an even multiple of the display computer’s frame-rate (for instance, when playing 25 fps video on a display computer set to 60 fps). This is accomplished by blending adjacent frames together, weighted by their temporal position in the sequence.

Dimensions
Enter the width and height of the video stream’s image, as dictated by the ­originating device. In the example above, this is the native resolution of the video camera.