Ever since thermography first arrived in the security sector, there has been some debate as to whether the benefits offered by the technology justify the cost of the thermal imaging devices. Now FLIR Systems has come to market with the FLIR TCX Mini, a miniature bullet thermal imager that costs the same as a budget video camera. Benchmark took a closer look to see if it represents a wise investment.
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[dropcap]W[/dropcap]hen thermal imaging first arrived in the security industry, it caused something of a stir. At exhibitions those companies demonstrating it regularly drew a large crowd. The technology was generally pitched in one of two ways: as a camera that could ‘see’ in the dark and in adverse environmental conditions (this is somewhat ironic as thermal images do not deliver images based upon visual elements, but use heat radiation instead), or as long range detection devices.
Whilst it must always be argued that no security solution should be selected or rejected on price alone, the crowds interested in thermal imaging thinned considerably as soon as the cost of the devices was revealed. Whilst the components used in the imagers were pricey, the issue wasn’t so much that people could not afford to implement thermography, but that it was difficult to justify the investment for a device that simply offered long range detection or around-the-clock low quality surveillance.
Both could be achieved using other technologies, and for a much lower capital investment.
The truth is that neither of the descriptions bandied around in the early days of thermography really do the technology justice, and as such it can be understood why the price barrier was seen as significant. However, as many installers and integrators have learned more about thermography, so the benefits of the technology have become better appreciated. This, plus economies of scale leading to lower cost imagers, have created greater interest in thermal imaging.
Many still have reservations over the cost of thermal imagers, and so the TCX Mini bullet thermal imager from FLIR is an interesting proposition. Designed to offer entry-level thermography at a very attractive price, the unit delivers thermal technology to a wide range of applications, but does it compromise on performance to achieve its market position?
Specification
Benchmark has a policy of not revealing pricing during its tests, but we do carefully consider the cost of devices to ensure we understand the price/performance ratio. The TCX Mini thermal bullet is difficult to assess without touching on price, because it breaks new ground in this regard by delivering a thermal technology device which is priced similarly to a budget video camera.
In the past there has been talk of more ‘cost-effective’ thermal imaging devices, although prices have remained doubled or trebled when compared with very high end video cameras. Therefore, the pricing of the TCX Mini is significant and must be considered against its performance.
The TCX MIni is billed as a thermal bullet camera and the description is accurate when compared to some of the heftier bullet-type cameras in the video space. The unit measures approximately 105 x 75 x 70mm, excluding the integral bracket. The housing includes an adjustable sun-shield and is rated to IP66.
The TCX Mini offers flexibility when it comes to connectivity. It can be added to an IP network, use a standard analogue video connection or make use of MPX connectivity. The latter is FLIR’s own megapixel-over-coax technology and is based upon HD-CVI.
The TCX Mini makes use of an uncooled VOx microbolometer which the manufacturer states is sun-safe. The resolution is 80 x 45 pixels. Now, if you’ve just read that and assumed that a couple of zeros have been missed off the specification, this isn’t the case. The sensor really is 80 x 45 pixels! However, it is presented as either a 1280 x 960 or 1280 x 720 format, making it compatible with most VMS and NVR solutions. Frame rates are up to 30fps.
There is a debate to be had as to how much resolution a thermal imager needs in a security application where its primary task is one of detection, and this is touched on in the section concerning performance. The low resolution thermal sensor is the price you pay to reduce the unit’s cost so dramatically.
The imager has a field of view of 25 degrees and a stated detection range of 40 metres. Detection ranges for thermal devices are based upon the Johnson Criteria, which specifies a size for target detection of two pixels. This is obviously different to the security industry’s definition of ‘detection’ and should be carefully considered.
Thermal image streams are delivered in H.264 or M-JPEG format, and the device includes integral motion detection with four independent masks deployable. In the case of an event, actions include email transmission, stream recording or capture of a snapshot. It offers support for privacy masking and AGC is supported for regions of interest.
The camera is billed as compatible with third party video analytics and is ONVIF Profile S compliant.
Power for the device is PoE; a standard low power 12V DC input is also supported.
The TCX Mini can be used with compatible VMS or NVR systems. Alternatively, the FLIR Cloud Client can be used. There is a dedicated FLIR DDNS to simplify remote connections.
The thermal imager is supplied with a quick connection guide and a quick networking guide, an MPX termination device (allows use with MPX devices), mounting template and fixing screws.
Installation
The first task when installing the TCX Mini is to download the required software and manuals. The quick start guide does give a URL for this, but the required downloads aren’t there. Instead you’ll have to do a bit of searching for them. We appreciate that FLIR is offering a low-cost device, but the lack of required software and manuals, even in digital format, doesn’t help with initial impressions.
Once the downloads are complete, you will need to install the FLIR Cloud Client. You need to do this even if you’re not using the company’s proprietary Cloud service. This is because the TCX Mini lacks an IP utility, and so the Cloud discovery feature reveals the unit’s IP address. We tried to change the TCX Mini’s address via the client, but this had no effect. Admittedly it was being used without a connection to the FLIR service.
The process is a little clumsy if you opt not to use the Cloud service: install the Cloud Client, connect the camera, search and discover it, note the details, change the LAN server IP, connect to the camera using a browser, change the camera IP as required, revert the LAN server and that’s it. You now have a TCX Mini with the required address. Given that you also need to find the software on the manufacturer’s website, it’s arguably quicker to set the LAN server to DHCP and look up the device’s allocated address at the switch!
Once the IP has been set, you can log into the TCX Mini with most browsers and complete the set-up process.
The menus are relatively straightforward, and due to the fact that the imager is very basic, there shouldn’t be any areas of concern for installers or integrators.
The viewing screen has options to select the stream (Main or Sub) and the transmission protocol. There are also options to select the display size and to initiate procedures such as snapshot capture and recording.
The set-up menus are Camera, Network, Event, Storage, System and Information. The sub-menus are fairly basic. Stream configuration is set via the Camera menu, with sub-menus for ROIs and stream quality. The latter is headed ‘Video’ for some reason, and allows the displayed resolution to be set, along with refresh rates and bit-rate (up to 8Mbps; given the quality and nature of the thermal stream, this is fairly generous). You can also set up Snapshot parameters, screen overlays (privacy masking, watermarking, date/time, etc.) and paths for saved footage and still images.
The Network sub-menus are self-explanatory, and include DDNS settings should you be using Cloud services or the FLIR DDNS option.
The Event menu is split into motion detection and device alert sub-menus. The former allows the creation of four detection areas, each with individual sensitivity and threshold settings. A histogram display assists with set-up. The latter covers disconnection, IP conflict and illegal access.
The Storage menus allow devices to be set to receive footage and snapshots, with options for FTP and NAS connections.
The final two menus – System and Information – cover logs, basic system details and housekeeping settings.
If you require remote connectivity you have two choices. The first, and most likely in a professional installation, will be to connect to the VMS or NVR using the established remote set-up, and the TCX Mini will be included amongst the channels. However, the thermal imager does allow a direct connection via the FLIR Cloud service. This might be used if the TCX Mini has been installed as a standalone device discreet from an existing solution.
Once the device has been set-up via the Cloud client, port forwarding is configured and the site can then be registered via FLIR’s DDNS service. Once this is completed, the Cloud client is used to remotely connect with the device, and a FLIR Cloud App is available for iPhone, iPad and the Android platform.
Because of the low price of the imager, the manufacturer clearly sees potential interest from users seeking a standalone thermal option. Whilst the TCX Mini will allow low-cost thermography in professional applications, it should be remembered that the device will also be made available directly to the consumer market.
Performance
Before taking a closer look at the performance of the TCX Mini, the issue of resolution must be addressed. It is important to consider thermal imaging for what it is: sensing of heat differentials. If you have a thermal image of an intruder, it doesn’t matter whether the resolution is 80 x 45 or 640 x 360; you are not going to be able to identify the individual in question.
In general security, thermal imaging will predominantly be used to detect the presence of an intruder. With regard to resolution, the biggest impact will be the number of pixels required to positively identify that the target is a human rather than an animal or other innocuous heat source.
Thermography has typically used the Johnson Criteria – a military scale created in the 1950s to rate the performance of night vision goggles – when it comes to judging detection distances. The military’s definition of detection is simply that there is something there, and as such detection requires just two pixels. For security, treating a two-pixel activation as an activation would cause a high degree of false alarms.
In previous Benchmark tests in real-world environments, we found that targets required a critical dimension of approximately 25 pixels for an operator to have a good degree of certainty of what they were viewing. For absolute certainty, that figure obviously rises. With lower resolutions, this results in a decreased distance of effective detection.
Understanding this is critical to assessing the TCX Mini. If you’re expecting the ranges offered by mainstream thermal imagers, you will be disappointed, and even the low cost won’t make up for that if the device doesn’t do what is required. However, if the range limitation is accepted and thermography adds to the level of protection, then the resolution might be less of an issue.
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Detection range is quoted as 40 metres. The sample images shown were captured over a distance of 20 metres. It must be said that still images lack the motion that made it clear the intruder was a human. When compared with thermal images from a 320 x 240 sensor, there is a clear difference in discernable detail. Despite this, if you view the TCX Mini as a detection device which allows an operator to establish the cause of an alarm, then it does what is needed.
Whilst many will caution against comparisons of thermal imagers with detection devices or cameras, the low cost of the TCX Mini does actually allow such comparisons. Whilst it won’t be the obvious choice in some applications, it does give installers and integrators another option. For those who can benefit from thermography and who have realistic expectations, it delivers a degree of protection which cannot be achieved with alternative units.
FLIR does state in its marketing material for the TCX Mini that the thermal imager offers, ‘the most accurate intrusion detection and video alarm verification system available’. Okay, all manufacturers have been occasionally guilty of over-gilding the lily, and that’s certainly the case here.
There can be no doubt that any form of motion detection or analytics is enhanced by the use of higher quality images, whether visual or thermal. It is equally true that the TCX Mini has restricted image detail, and its on-board functionality is limited to motion detection. This has been tweaked to deliver a decent degree of stability, and set-up is enhanced through the use of a histogram. However, the function is more effective when used over a fairly short range. If used over longer distances then most heat sources will trigger an event.
The approach that must be taken to motion detection is very much like the approach required to ensure that a deployment of the TCX Mini meets expectations and satisfies a site’s requirements: apply common sense!
The TCX Mini isn’t a high performance device. However, it places thermal imaging – and the many benefits of the technology – into an affordable space. It’s hard to imagine an application which would be put off by the price tag where thermography could offer a benefit, and that’s what sets this apart from the majority of other imagers.
Verdict
The TCX Mini thermal bullet from FLIR is a significant entry into the security market. It represents a basic but functional thermal imager which is around the cost of an entry-level video camera or a good quality external detector. Whilst this means it can supplement standard security devices, it also offers a wide range of benefits that only thermal imaging can provide.
There will be some who dismiss the TCX Mini as being too low performance to be credible, but generally these will either be those who don’t have experience of the benefits of thermal imaging in real-world applications, or who have not fully considered how the technology can be applied.
There are things that could be improved: inclusion of the full manual and software utilities would be a good start, and a basic utility for IP-setting for those who won’t use the Cloud service would also be a benefit. Any other additions would be less of a ‘gripe’ and more of a wish-list, and would inevitably push the price of the unit up.
When it comes down to it, the price of the TCX Mini is its headline feature. As FLIR’s low-cost core becomes used by more manufacturers, the industry will start to see the impact of this unit’s legacy.
Ultimately, the TCX Mini thermal bullet achieves Recommended status, but with the proviso that installers and integrators must ensure that they manage users’ expectations.
If the customer is aware of the level of performance they will receive, the benefits of thermography over external detection or video surveillance, and the way in which the technology can be implemented, then they are unlikely to shun such a cost-effective entry into thermal imaging.