2N Helios IP, Руководство по настройке

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Explanation of Terms
RTP (Real-Time Transport Protocol) – is a protocol defining the standard packet
format for audio/video transmission via IP networks.
employs this 2N Helios IP
protocol for audio/video streaming. The RTP transport protocol is either UDP or
also RTSP and HTTP.
RTSP – is a network protocol for streaming (Real-Time Streaming Protocol)
server control (controls setting up, launching and stopping of audio/video
streams).
HTTP – helps transmit practically any contents (Hypertext Transfer Protocol)
and is used primarily by internet browsers for web server communication. 2N
uses the HTTP to transmit static JPEG images or MJPEG streams via Helios IP
the HTTP Server Push.
IP Multicast – is a way of parallel sending of IP packets from one source to
multiple stations via IP networks.
uses IP multicast for sending and 2N Helios IP
receiving audio streams.
ONVIF (Open Network Video Interface Forum) – is a set of video camera search,
configuration and administration specifications for the IP network. The 2N Helios
intercoms are ONVIF compatible and fully implement the ONVIF Profile S. IP
JPEG – is a standard method of lossy compression of images.
MJPEG – is a video stream encoding format in which each image is compressed
separately by JPEG. MJPEG encoding produces high-quality video at a
significantly higher bit rate compared to the methods mentioned below.
H.263 – is a video stream compression standard used in telecommunications.
Unlike MJPEG, H.263 uses differences between consecutive images and provides
a significantly higher level of compression to the detriment of the video stream
quality.
H.263+ – is like H.263, but supports a different bit stream packetisation method.
MPEG-4 part 2 – is a video stream compression standard used mostly in areas
other than telecommunications, but often supported by IP camera and video
surveillance systems. In
, the compression level and image quality 2N Helios IP
are comparable with the H.263 standard.
H.264 – is a video stream compression standard. Compared to H.263 and MPEG-
4, H.264 provides an approximately identical level of video stream quality but a
half bit rate. This type of compression is sometimes called MPEG-4 part 10.
G.711 – is one of the most common audio transmission standards in
telecommunications. It uses the sampling frequency of 8 kHz and data are
compressed using logarithmic compression.