Specifications

Security and surveillance
IP cameras
www.digikey.com/maxim-industrial 123
IP cameras
Overview
IP cameras use the Internet protocol
(IP) to transmit audio and video data,
along with control signals, over
Ethernet links in closed-circuit televi-
sion (CCTV) systems. They offer
numerous advantages over traditional
analog security cameras, which
typically transmit an analog NTSC/PAL
signal over coaxial cable. Unlike analog
cameras, IP cameras support high-
definition (HD) images, intelligent
analytics, local video storage, and
remote control.
Video compression is performed in
the IP camera together with analytic
functions, video encryption (to stop
hackers), and encapsulation of video
data into Ethernet packets. The
compressed video stream is usually
sent to a hybrid digital video recorder
(DVR) or network video recorder
(NVR) for storage, playback, and
display. The use of an IP network for
video monitoring can enable security
staff to be located at geographically
remote locations, allowing central-
ized control over security cameras
across campuses or multiple sites
using pan-tilt-zoom (PTZ) commands
sent over the IP network.
Low-power camera designs can be
powered over Ethernet (PoE) without
additional power sources. By using the
same cable to transmit both data and
power, PoE installations can substan-
tially reduce cabling costs. In some
cases, wireless networks such as Wi-Fi®
can be used to replace Ethernet, thus
easing camera placement. This is espe-
cially true of home security cameras
where Ethernet wiring may not be
readily available, and where “cloud
computing” DVR applications replace
physical DVRs.
Multistream H.264 and
Motion-JPEG compression
The H.264 video compression
standard provides approximately
twice the compression of the
previous MPEG-4 standard for the
same video quality. Within the
H.264 standard, the “high” profile
defines the highest video quality
with the lowest bit rate, making it
especially relevant for applications
such as video security. Achieving
very-low-latency (delay) encoding
minimizes the response time from
security personnel. Meanwhile, high-
definition video encoding enables
the IP camera to capture details such
as facial features and license plates
for enhanced security imaging. Since
network bandwidth may be limited,
systems can require the ability to
encode/record one HD stream over
a local area network (LAN) while
simultaneously streaming a lower
resolution feed for remote viewing
over a wide area network (WAN).
In addition to H.264, many security
systems require backward compat-
ibility with existing equipment that
does not support H.264. The Motion-
JPEG (M-JPEG) standard can provide
backward compatibility in such
systems, as well as the ability to take
high-resolution lossless snapshots.
Specifically, it supports simultaneous
encoding of H.264 video for unin-
terrupted video recording while
capturing JPEG still images, which
may be driven by specific events.
Analytics
Video analytics is the process of
analyzing video data and making
decisions based upon it. Supporting
analytics in software within the
camera enables actions to be taken
immediately based on specific events
and without the need for inputs from
security personnel. For example, an
alarm may be sounded if the camera
detects that a person has crossed
into a secure area. Analytic functions
include motion detection, trip wire,
and image tracking. All of these
functions need to be configurable
from the PC-based security manage-
ment software using an intuitive
graphical user interface (GUI).
MICROPHONE
128MB DDR2
10/100
ETH PHY
CMOS
SENSOR
COMPOSITE
VIDEO
DECODER
CONFIG
SWITCH
VIDEO
ENCODER
NAND
FLASH
SD CARD
SLOT
= MAXIM SOLUTION
GPIO
HEADER
UART DBG
UART
USB HOST
CONNECTOR
ETHERNET
SPEAKER
COMPOSITE
POWER
SUPPLY
PoE
POWER
SUPPLY
POWER
SUPPLY
SUPERVISOR
TEMP SENSOR
UART
XCVR
H.264
CODEC
SoC
ADC/DAC
SPEAKER
AMP
RTC
INTERFACE
PROTECTION
IP camera block diagram. For a list of Maxim's recommended solutions, please visit: www.maxim-ic.com/IPcamera.
Mobicam3 720p H.264/M-JPEG IP camera reference design