Holiday season is closing in and a lot of home owners will have to look at
how to protect your home before going away on holidays. Don’t wait until last
minute. It is not very wise to set up your surveillance 2 or 3 days before
leaving home just to find out the program has crashed on the first day you are
on holidays elsewhere.
In the following article, Bob gives some tips for how to plan, set-up and
test a Netcam Watcher system.
All systems are different so not everything in this article will apply to
your setup. But we are happy to help you at any stage of the process - just
contact Beausoft Ltd.
Planning
This includes figuring out how many cameras you need, what kind of cameras
to buy. Also, what kind of PC to use, how much storage is needed and so on.
Cameras
Nowadays there is a bewildering range of IP cameras available, and it can
be hard to figure out which ones to use.
The first thing is to decide on your requirements :
-- which camera(s) need to be
outside and which need to be inside?
-- do you use fixed or pan/tilt cameras. Or pan/tilt/zoom (which are more
expensive) ?
-- what resolution do you need? Typically cameras go from VGA (640x480) up
to multi-megapixel. Of course, normally the higher the resolution, the higher
the price. But also with larger frames comes slower frame rates (all else being
equal) and increased storage needs.
-- Connection : do you want physical network connections or wireless
connectivity?
-- Power : Do you need POE (power over ethernet) or is power from a
"wall wart" OK?
Once you have defined these basic parameters you are ready to go looking
for cameras. You can contact us at this point and we can give you a list of
cameras to look at.
Netcam Watcher PC
wIt's very important that you use a PC that has enough CPU power to handle
the load that your cameras will throw at it. Netcam Watcher is a CPU-intensive
application - it takes a lot of processing power to decode images (from jpeg,
mpeg4 or h.264) and to perform motion detection.
So, how do you decide if a particular PC is up to the job? Or, if you need
to buy a new PC, which PC to get?
This can be a surprisingly difficult task. This is mostly because systems,
cameras and your own requirements are all different.
For some people, 1 frame per second (fps) is great (e.g. if you are
monitoring progress on a building site), for others, 1 fps is a disaster.
Then there is frame size - the normal frame size for many cameras is VGA.
This uses 0.3 megapixels. Going up to HD, 720P resolution (1280x720) uses 1
megapixel, and full HD 1080P (1920x1080) requires 2 megapixels.
So you can see that one 1080p frame is equivalent to six VGA frames!
It's a good idea to decide what frame sizes and rates you deem to be
acceptable. To give some idea :
- 5fps looks like jerky video;
- 10fps is getting smoother
- 20fps is full motion smooth video (broadcast quality is only 24fps).
So at this stage, you should know:
-- how many cameras you have (or will have)
-- what frame sizes-- what are your target frame rates
Now the next thing is to convert your frame sizes to "VGA
equivalent" frames.
For example, if you want to run a camera at 720P, multiply the target frame
rate by 3. For 1080p, multiply by 6
This lets you calculate the total "VGA equivalent" frames per
second that you want the whole system to do.
Here's an example:
-- 4 cameras. 1 is VGA, 2 are 720p and 1 is 1080p
-- target frame rate is 20fps
So the overall "VGA equivalent" frame rate is 20 for the first
camera, 20*3, or 60 for the second and third cameras, and 20*6 or 120 for the
last camera.
This gives a total of 20+60+60+120=260 VGA Equivalent frames per sec
(VEFPS).
We find that usually the CPU is the limiting factor up to about 450-500
VEFPS, but once you hit that range, the network becomes the bottleneck.
This figure depends a lot on the compression that the cameras use - h.264
cameras will not saturate the network anywhere near as easily as MJPEG cameras.
However, h.264 cameras need a little more CPU as decoding takes more cycles.
Now the next job is deciding on a CPU, or deciding whether a given CPU is
up to the job. This is an inexact science, and this part is for guidance only,
but it should give you an idea.
I find that a good measure of a CPU is it's Geekbench score. You can search
for a particular PC or CPU in the Geekbench Results Browser and get an idea of
the scores that a particular CPU can do.
Note that you will see a range of scores for a specific CPU - choose the
lower figures as the higher ones are often obtained by enthusiasts who tweak,
tune and overclock their CPUs.
Geekbench results for a CPU range (currently) from 1000 for an old Celeron
to about 17000 for a fast i7
So, here's a rough guide of CPU score vs VEFPS
VEFPS Geekbench Score
<20 Any
60 2500
100 3500
150 4500
250 6000
450+ 8000+
Bear in mind that these figures relate to Netcam Watcher v3.3. Older
versions (eg 2.5a and earlier) are slower (ie they need more CPU power for the
same performance, up to a factor of 2)
Also, h.264 and mpeg4 cameras need
more CPU cycles to decode frames, so they need more CPU power for the same
VEFPS
Other PC features
OK so that has the CPU sorted. The rest of the PC is quite straightforward:
-- use Windows 7 64 bit if you can. DO NOT use Windows 7 32 bit - this does
not work properly with Netcam Watcher (and in fact has bugs with all sorts of
software)
-- Netcam Watcher does not use a lot of memory. But the system can benefit
from as much memory as possible as unused RAM is used as disk cache. Normally
use 4GB or more RAM
-- There's no need to get a super-fast gamer-style video card as most of
the features of such cards are not used (eg 3D processing). You may want to
consider a video card that supports multiple monitors.
Disk Storage
Like CPU sizing, working out how much storage to have is a fairly complex
subject. However, storage is cheap nowadays - a 2TB disk sells for around
us$150. And a new PC nowadays usually has at least 6 SATA ports, so even
allowing one for a DVD, you can easily and cheaply outfit a PC with 10TB of
disk storage, a feat that would have cost hundreds of thousands of dollars a
few years ago.
So my advice is to load up your PC with as much disk storage as it will
take!
But here is how to estimate how much disk space you will need.
Firstly you need to answer the basic question: how long do you want to
retain recordings for?
Another thing that greatly impacts the disk space requirements is motion
detection. Most people use Netcam Watcher's motion detection feature. This
reduces disk storage by up to 90% as you only
record frames where motion occurs.
Here is the procedure for calculating disk usage:
1) Record a test clip from one of each type of your cameras. Set NCW to
"record every frame". Record for exactly one minute.
2) Note the file size; multiply by 60 to get the hourly disk use.
3) Now you can calculate the usage for all your cameras, per hour.
4) It's a simple matter to multiply by 24 to get the daily usage, and by
your retention period to get the total.
Example : 20 cameras, each VGA, retention period 7 days
1) Test clip for one minute : 62524KB = 62MB
2) 62x24=1488MB (or say 1.5GB) per hour for one camera
3) 1.5x20 = 30GB per hour for 20 cameras
4) 30x24 = 720GB for 20 cameras per day. Or 720x7 = 5TB for 20 cameras for
7 days.
BUT : These figures are if you "record every frame", 24 hours a
day! Even then we are talking about $450 worth of disk storage. For almost 400
million frames!
If you use motion detection it's likely that your space requirements will
only be 20% of that figure, or 1TB. How much you can expect motion detection to
reduce your space needs depends entirely
on your situation - whether you are monitoring a busy street or a high
security area with few visitors.
Setting Up
Cameras
How you set up your cameras depends on the type of camera, and instructions
should come with the cameras.
However one thing to watch is how the IP address of the camera is set.
Often the default is "DHCP" which means that the IP address is
assigned by the network controller, usually your router.
This is NOT what we want! Why? Because if you power off/power on your
camera the controller may give it a completely different address. And we want
the address to stay the same (otherwise Netcam Watcher will not be able to find
the camera).
The solution is to set the IP address to STATIC. Actually it's a good idea
to let it be assigned an IP during setup, then to make that IP static, thus
ensuring that the address you choose is available.
PC Side
Setting up Netcam Watcher is fairly straightforward. Download and install.
Enter your registration code and restart.
Now you can define your cameras. Do Edit >> Create New Camera and
enter the details. Repeat for each camera.
Also you may want to set up one or more of the following:
-- Alarms (Alarms menu)
-- Schedules ( Edit > Schedules )
-- Motion Detection Settings (click on motion bar, bottom left)
-- Recording Retention Settings
(Edit Cam, Recording and Saving panel )
-- Archiving and Backups ( File > Preferences, Archiving and Backup
panel )
AlwaysUp
We strongly recommend using AlwaysUp to control NCW. It restarts NCW after
a crash, or if someone stops it. It starts NCW after a reboot. And it can
notify you of these events.
How to set up AlwaysUp is described here
When to set up?
Possibly the most important thing when setting up a system : Do not leave
until the last moment.
Leave at least a week, ideally two weeks before you need to use the system
in anger. If you do not follow this advice then it's quite likely your system
will not work as you expected.
This point is related to another often overlooked part of setup : Testing.
Testing
If you want your system to work properly you MUST test it.
Here are a set of tests that are the minimum you need to perform to verify
that things are working as you expect.
-- Basic Recording - if possible, walk in front of each camera and then
check that you are recorded properly. If it's not possible due to location, pan
or tilt the camera, or simulate movement some other way.
-- Try to close Netcam Watcher - does AlwaysUp restart it OK?
-- Pull the power lead out of the PC (simulating a power cut). Plug the
lead back in. Does the PC boot up properly, run Netcam Watcher and start all
the cameras? Are the cameras recording OK
after this?
-- Power off each camera and power back on. Do they continue to record
after a couple of minutes?
-- Power your router off and on. Does the system recover OK?
Finally..
If you have any problems or questions, we are here to help.
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