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How many MegaBytes in a GigaByte?

January 14th, 2009

Google logoHard disc drives continue to get larger all the time, especially when you need them to record megapixel CCTV cameras 24hrs per day.

As unlikely as it seems, we are now headed towards 2 TeraBytes on an SD card!

We’ve covered this topic of MegaBytes, GigaBytes, TeraBytes and PetaBytes before, but we realise that it still confuses people, so we just thought it might be worthwhile mentioning Google’s inbuilt converter and calculation functions for those that aren’t already aware of them.

If you want to know exactly how MegaBytes compares to GigaBytes (or whatever), just type your query into Google’s search box in the following format:

500MB in GB

Google’s first ‘search result’ will be:

500 megabytes = 0.48828125 gigabytes

You can use this for any conversion using:

KB = KiloBytes

MB = MegaBytes

GB = GigaBytes

TB = TeraBytes

PB = PetaBytes

It also works for other conversions:

4 pounds in kilos

4 pounds = 1.81436948 kilograms

2 feet in cm

2 feet = 60.96 centimeters

Google will also tell you the current time in most World Cities:

time Brisbane

10:18am Wednesday (EST) – Time in Brisbane, Queensland

Brisbane, California 4:18pm -1 day PST

Hope that’s handy to know?

IRE and Lux Light Levels

January 12th, 2009

IRE for CCTV Lux

What does IRE mean when quoted with Lux light levels for CCTV cameras?

We’ve noticed that many people seem to be a little baffled by this mysterious occasional mention of the term IRE, so we thought we’d just write a quick article to explain it in lay terms for you.

There is a good technical explanation over on Wikipedia, but as often happens it is a bit too technical if you are starting from the point of having no idea!

IRE stands for Institute of Radio Engineers, but that’s not important, you want to know what it means.

Well, keeping this within terms easily understood by lay-men:

The squiggly line above represents a composite video signal.

We refer to a good signal as being 1 volt peak-to-peak.

The Institute of Radio Engineers came up with the term IRE to represent the composite video signal in percentage terms i.e. 100IRE equals 100%, a full (good) signal.

Now the buyer beware bit. Just about the only time you see IRE quoted is when a manufacturer is trying to apply specmanship i.e. they are claiming that their camera can ‘see’ in very low light levels, but in fact it only does so poorly, and produces a less than good composite video signal.

For example 0.05 Lux (30IRE) means that in light levels measured at 0.05 Lux the camera will produce an image, but it’ll be a poor one, with a composite video signal level at only about 30% of what it should be. Effectively this would be a fairly useless image, and perhaps the camera is only really useful down to a higher lux level of say 0.5 Lux …

Of course, due to our human tendency to ignore the bits we don’t understand, it makes for quite clever marketing really; most folk just read the specification, see the incredible ‘see-in-the-dark’ capability indicated by the very low lux light level claimed in the specification and proceed to buy the camera.

To gain a better understanding of relative lux light levels take a look at our free chart.

Hard Disc Drive Storage for CCTV Surveillance

January 10th, 2009

veracity logo

Veracity mentioned this article on their website in an email I received recently; it’s a good write-up on the use of hard disc drives in modern CCTV video storage. The article isn’t new but it provides a lot of useful information and we think it’s worth pointing it out to you:

The most obvious current trend in video surveillance is the slow evolution from analogue cameras to IP cameras. Industry vendors of recording systems appear to be divided into two camps : the sceptics, who are wondering when the IP video revolution is really going to take hold, and the informed, who know it is already here and are just getting on with it.

Although the IP video segment of the UK market is currently only around 15%, it is growing rapidly. In Europe, where analogue CCTV cameras are not so entrenched, the growth rate is even steeper.

One of the things that has held back IP video systems up to now is the lack of any real reason for users to switch, even for new installs. What would they have gained, bar a little increased flexibility ? Now, in 2007, the story is quite different : most well-designed IP cameras are progressive scan, at long last leaving behind the problematic interlaced image legacy of the broadcast TV standard. Further, and more importantly, mega-pixel cameras (with resolutions way beyond HD TV) are now here and affordable. At long last, mega-pixel cameras provide the compelling reason to switch to IP-based systems. The improvement in image quality offered by high-quality mega-pixel cameras in nothing short of dramatic, even breathtaking. Another problem which has held back adoption of IP cameras is the vast amount of legacy co-axial cabling installed in existing systems. However, several vendors are now offering Ethernet over-coax solutions, so this is no longer a barrier at all.

Well worth a read, to aid your understanding of the use of big HDDs, RAID storage and potentially high disk failure rates.

CCTV Training Courses

January 3rd, 2009

CCTV Training CoursesCCTV and Security training is attracting a lot of interest at the moment.

We’re in a recession, and a lot of folk are losing their jobs.

Those people are looking around for a new career, perhaps in a technology with a future …

They see upcoming major projects such as the 2012 London Olympics creating a great demand for CCTV and other security services.

They are looking to re-train and to pick up new skills, seeking courses to attend which will provide them with the new skills they seek.

Some are in the market for a career change into a new and more interesting field of work associated with developing technologies such as IP CCTV.

Common questions include:

  • Where can I attend a CCTV training course?
  • How much does it cost?
  • What previous experience or qualifications will I need?
  • What will employers expect?
  • Are there any jobs?
  • Where are vacancies advertised?
  • How can I start my own CCTV company?

We have a great deal of experience in the UK CCTV market, please feel free to Contact Us and we’ll gladly provide you with some pointers to guide you in the right direction in these difficult and changing times.

Update, due to lots of enquiries on this topic:

From personal experience we are happy to recommend Tavcom for CCTV Training.

Other possibilities include:

CCTV Training & Logistics

CCTV Cameras Provide Vital Evidence

January 3rd, 2009

CCTV evidence is vital

CCTV cameras have proved as vital to Scotland Yard detectives as forensic evidence such as DNA samples or fingerprints.

Commander Simon Foy, Scotland Yard’s head of homicide, said:

CCTV plays a huge role in helping us investigate serious crime. I hope people can understand how important it is to our success in catching people who commit murder.

Will the results of this study by the Met Police bring an end to the “Is CCTV worthwhile?” debate?

Good to see my favourite ‘CCTV Facts’ quoted again – 4.2 million cameras, people in London are filmed up to 300 times a day – I first put those on a web page about 5 years ago and frequently received calls from the media …

Read the full story about this first study into the effectiveness of surveillance cameras in helping UK Police solve crimes over at The Daily Telegraph website.

There wasn’t much doubt about the efficacy of UK CCTV in the aftermath of the London Bombings; the UK Police were able to establish so much factual information so quickly that some other european countries quickly set about changing their laws so that they could install similar systems …