In recent years the use of thermal imaging products in security applications has become more widespread. As the cost of the devices has fallen, an understanding of the benefits of the technology has increased demand for the use of thermography. This is especially true with regards to perimeter protection and video analytics, both of which are good fits for the technology. Mobotix has adopted a decentralised and modular approach to video surveillance and its popular M16 cameras can be specified with a range of modules, including a thermal option.
Thermal imaging had a slow start in the security industry for two main reasons: it carried a high cost and there were mixed messages about what it offered. Thanks to economies of scale from outside of the security industry, the general cost of thermal imaging cores has been steadily falling and the prices are much more realistic for many mainstream applications. More importantly, installers and integrators – along with end users and consultants – have a better idea of the benefits of the technology.
When thermal imaging first arrived in security, the general message was that it was a surveillance technology. Benefits such as around-the-clock performance and delivery of streams in fog, smoke and adverse environmental conditions were pushed hard by those selling the solutions. However, the message wasn’t well received because unlike video, thermography will not deliver streams that can be used for the positive identification of individuals.
If this was raised as an issue, the sales message often changed to one promoting thermography as a long range sensor that provided visual verification of any events.
While thermographic devices do indeed fulfil roles in surveillance and detection, it is hard to compare the technology with the standard industry understandings of those two sectors. In truth, thermal imaging works best when linked with other technologies and can add value in a wide range of critical applications. Thermography can also meet the needs of safety applications.
When it comes to perimeter protection, applications with a critical need for situational awareness or the use of analytics as a multi-layered solution, thermography offers a wide range of benefits that actually make the devices very cost-effective.
Specification
Mobotix has never been afraid to plough its own furrow and the M16 range is no different. The cameras are modular and can be fitted with a number of different modules, dependent upon the needs of any given site. Each M16 can be fitted with one or two modules: optical day/night, thermal or thermal-TR. The latter includes temperature measurement as well as standard thermal imaging.
Where one thermal and one optical module are fitted, this allows both video and thermographic streams to be captured; there is also an option for thermal overlays: more about this later.
The thermal core makes use of a 336 x 252 pixel sensor fitted with a Germanium lens. Streams are up to 9fps. Options for the field of view are 45, 25 or 17 degrees. The thermal image can be displayed using the traditional black and white pallette, along with false colour options.
The TR version offers temperature measurement across the whole scene, with an accuracy of ±10 degrees. The standard thermal unit also offers temperature measurement but only uses a 2 x 2 pixel ‘spot’ in the centre of the image and accuracy is ±20 degrees. For many security applications the TR version might not be necessary, but in some applications such as safety, process control or system monitoring this can add value. Both the standard and TR versions of the device offer the same performance aside from this one feature.
The optional optical camera modules are 6 megapixel (3072 x 2048) devices that make use of a 1/1.8 inch CMOS sensor. Supported video formats include MxPEG (a Mobotix proprietary algorithm), H.264 and M-JPEG. Frame rates using MxPEG are 42fps at 1280 x 720, 34fps at 1920 x 1080, 24 fps at QXGA, 15fps at 5MP and 12fps at 6MP. With H.264 these fall to 25fps at 1920 x 1080 and 20fps at QXGA.
Mobotix has always followed a ‘decentralised’ approach, in that its cameras are effectively standalone miniaturised systems. As well as video and thermal capture the units include an integral PIR sensor, microphone and speaker, integral archiving onto 4GB SD card and an optional I/O device is available.
Features include constant and event-based recording with audio, digital PTZ, snapshot recording and privacy masking. The cameras also make use of MxActivitySensor. This makes use of intelligent 3D motion detection that compensates for movement caused by birds or small animals).
The M16 cameras are rated to IP66 and make use of standard PoE. The devices are supplied with a quick start guide but full documentation does require the installer or integrator to visit the Mobotix website to download manuals. During our test the M16 manual link was live but it downloaded the wrong file; the two page quick start guide (which is included with the device) was the only documentation available.
If you are stuck it is likely that some of the other manuals will cover the information you need. That said it is something Mobotix should address if they don’t want unhappy customers or an excessive number of technical support calls.
Installation
When setting up the camera the first task is to select a boot mode. There are three choices for the thermal model. These are factory defaults using the standard IP address and authentication details, booting as a DHCP client or system recovery which can be used in the event of a failed software update.
To select the boot mode you need to power the camera on and whilst the red LED is illuminated (around 10 seconds) a paper clip is used to press a mode button. This will initiate the boot mode. You then press the mode button to cycle through the boot options and once it is set a longer press initialises the device. It will then start up and play an audio clip to identify which boot mode is active.
If opting for the default setting (as we did), the device’s static IP address is included on a sticker attached to the camera. This will be in the 10.x.x.x range and so most installers and integrators will change this. You will then need the default authentication details to log in to the camera. These are not included in the quick start guide. We used documentation for another device and thankfully it was the same.
From this point you can log into the device, set the various configurations and configure the features and functions. Changing the password is obviously an important task but the camera does not enforce this, although it does display a warning about authentication details.
The manual states that if the password details are lost the camera will need to be returned to the factory for a reset and a fee will be charged. While carrying out a factory default reboot will reset the configurations it does not include user authentication data.
There are two configuration menus; admin and set-up. Both are relatively straightforward and engineers should have no issues configuring the camera. Many of the screens contain simple drop-down menus for adjustments, making the process relatively simple.
Performance
With regard to thermal imaging streams, the quality is on a par with what you would expect from many security-biased thermal imagers. The effective distance for recognising human activity will very much depend upon the application and the specification of the lens. However, with our test unit which was fitted with the 45 degree lens, ranges of up to 100 metres were handled without any issues.
The temperature measurement function is something that is probably more niche than many security-biased end users will require, but it’s there if it’s required. The set-up is marginally frustrating; we used a manual for a different camera and the on-device help pages to set the function up. The latter does include hot links which made locating the relevant information simpler. The downside is that we ended up with too many web pages opened which made the configuration cumbersome at times.
One feature that is a benefit is the use of a thermographic overlay. This means that if the visual camera is partially obscured, such as if there is smoke or mist in the scene, the overlay indicates that a person or object is there, albeit one that is difficult to see in the video image. Again, not every application will require this functionality, but it could add value for sites where health and safety is a prime concern.
The overall thermal imaging performance is very good and will certainly be more than adequate for a wide range of applications. It has some nice additional features which elevate the camera above some of the more basic products that are available.
The fact that the M16 can support dual camera modules makes it simple to combine video alongside the thermal stream. While the test predominantly focused on thermal performance, the video quality is good with a high degree of flexibility. MxActivitySensor has been tested by Benchmark in the past and the latest version has some added capabilities, such as size discriminations which do allow a more filtered use of the feature. Nuisance alarms are minimal and during the test the camera did not miss any genuine events.
As is typical from Mobotix products, the camera is so much more than a camera and everything works well. Quality is high and there’s not much that will raise concerns for professional installers and integrators.
Verdict
To consider the M16 Thermal TR as a thermal camera, or even as a dual module camera, is to miss its point. It is very much a standalone surveillance system and can be deployed as such. Obviously most users will link units and use a VMS for centralised control, but if there is an issue the camera can pretty much continue operating if it has power.
There is only one small downside. Because of the way Mobotix has designed its products there are some differences between configurations for their products and other cameras. Having to use incorrect manuals isn’t a positive. The camera does have on-board help files but the process is somewhat cumbersome.
That said, performance is very good and there is a depth of flexibility on offer. As with any device, familiarity does make configuration easier but there’s nothing here that is a deal-breaker. The final quality makes the effort worthwhile.
As such, the M16 Thermal TR achieves Benchmark Recommended status.