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2.6 Video stream types
Motion JPEG
This format uses standard JPEG still images in the video stream. These images are
then displayed and updated at a rate sufficient to create a stream that shows
constantly updated motion.
The Motion JPEG stream uses considerable amounts of bandwidth, but also
provides excellent image quality and access to every individual image contained in
the stream.
H.264 protocols and communication methods
• RTP (
R
ealtime
T
ransport
P
rotocol) is a protocol that allows programs to manage
the
real-time transmission of multimedia data, via unicast or multicast.
• RTSP (
R
eal
T
ime
S
treaming
P
rotocol) serves as a control protocol, to negotiate the
type of transport protocol to use for the stream. RTSP is used by a viewing client to
start a unicast session
• UDP (
U
ser
D
atagram
P
rotocol) is a communications protocol that offers limited
service for exchanging data in a network which uses the Internet Protocol (IP). UDP
is an alternative to the Transmission Control Protocol (TCP). The advantage of UDP
is that, it is not required to deliver all data and may drop network packets when there
is network congestion. This is suitable for live video, as there is no point in re-
transmitting old information that will not be displayed anyway.
• Unicasting is communication between a single sender and a single receiver over a
network. This means that the video stream goes independently to each user, and
each user gets own stream. A benefit of unicasting is, incase one stream fails, it only
affects one user.
• Multicast is bandwidth-conserving technology that reduces bandwidth usage by
simultaneously delivering a single stream of information to multiple network
recipients. This technology is used primarily on delimited networks (intranets), as
each user needs an uninterrupted data flow and should not rely on network routers.
2.7 How to stream H.264
Deciding on the combination of protocols and methods to use depends on your
viewing requirements, and on the properties of your network. Setting the preferred
method(s) is done in the control applet for AMC, which is found in the Windows
Control Panel. When this has been set, AMC will test all the selected methods in the
specified order, until the first functioning one is found.