In the world of video surveillance, HD1080p has become the de facto standard for any sites that take security seriously. There are many manufacturers offering such devices, and one – Axis Communications – has a number of models that are proven in the field. The range has now been expanded with the Q1615, which adds a more advanced feature-set with the goal of delivering consistent high end performance. Benchmark took a closer look at the new camera to see what degree of value it adds to the range.
[dropcap]W[/dropcap]hen HD cameras first appeared in the surveillance sector, their main appeal lay in the fact that the devices could stream an understood and accepted high resolution video stream. The ‘HD’ designation was a significant benefit in itself, and at the time this meant that the various compromises the technology introduced weren’t a major concern. The fact that HD streams were being delivered was enough!
Today, things have changed. HD cameras are common, and many of the technology’s weaknesses are well understood. Often the general image processing isn’t as good as that of traditional cameras. This is because more processing power is needed to deliver multiple streams of high resolution video, leaving less for everyday functionality.
Of course, as with any emerging technology, the development of HD cameras is on-going. In truth, when considered against the development of other security technologies, it is moving at a pace that is quite breathtaking. Certain manufacturers who decided to deliver true high quality HD video at the early stages of development are now concentrating on the other performance issues, and slowly but surely their HD cameras are delivering on all fronts!
Over the years Benchmark has tested a large number of cameras from Axis Communications. These have ranged from the over-priced under-performing units of the earliest days of IP video, through to today’s devices which are often amongst the highest rated when we carry out comparative performance testing.
The initial sample we received of the Q1615, the flagship model of the Q16 range, had a number of issues. Colour fidelity was poor, general processing for the advanced functionality wasn’t correct, and the camera was prone to erratic behaviour and instability. As a result, a replacement was requested. Axis Communications was not informed of the types of problems we had experienced. The test was carried out on the replacement unit.
Specification
The AXIS Q1615 is an HD1080p camera which delivers streams at up to 50fps. The camera uses a 1/2.8 inch CMOS sensor, and video is compressed using H.264 (baseline, main or high profile) or Motion-JPEG. Multiple streaming is supported. There is a note about the faster frame rate: this drops to 25fps if WDR functionality is employed.
Sensitivity is claimed to be 0.36 lux (F1.3) at 50fps, or 0.18 lux (F1.3) at 25fps. The camera includes the manufacturer’s Lightfinder technology.
The camera supports WDR functionality, and bills this as WDR Forensic Capture. This allows critical detail to be captured in challenging conditions, according to the manufacturer. There is also a shadow and highlight recovery function. The Q1615 has two operational modes: HD1080p at 50fps without WDR functionality, or HD1080p at 25fps with WDR functionality.
The Q1615 allows the use of downloadable apps, which are available via the Axis Camera Application Platform. The test focused upon the camera’s performance, so this feature and the associated apps are beyond the scope of this report.
Other features include electronic image stabilisation, two-way audio, remote back-focus, BLC, AGC, privacy masking, lens barrel distortion correction, alarm I/Os and shock detection. The camera also supports video motion detection, audio detection and sabotage protection.
Edge recording is catered for with an MicroSD-XC card slot (the specifications state it is an SD-XC slot, but it’s definitely the smaller format). Power is PoE; 12V DC power is also supported.
The camera is supplied with a basic stand and a 2.8-8mm varifocal IR corrected P-Iris megapixel lens from Fujinon. It should be noted that camera has functionality which is specific to certain lenses. There are a few options, including the supplied lens. Generic lenses can be selected if required.
There is also a CD with user and installation guides plus software and utilities, and various connectors.
Configuration
For many years Axis has shipped its products with a simple configuration utility, and the Q1615 is no different. The utility immediately found the device and allowed the IP settings to be changed. Once this process completes, you either log in to the unit’s web server, or simply double click in the config tool and the page will load.
There are some initial tasks which must be completed. The first is to set a password, followed by selecting a capture mode (HD1080p 25fps with WDR, HD1080p 50fps without WDR or 1920 x 1200 25fps without WDR) and finally selecting the frequency for flickerless mode. There is also an option to upload a PTZ driver if required.
The ActiveX element for set-up viewing automatically loads, and if you want to view the streams in H.264 then a supplementary codec needs to be added. Both installations worked as expected, and the elements are compatible with the latest version of Internet Explorer.
The menus are standard for Axis cameras, although the added functionality does introduce more settings. There isn’t anything that will challenge a competent person, and the general layout is simple.
The auto-focus function works well, and is relatively fast.
Performance
To start with, we selected the HD1080p 50fps without WDR capture mode. Once the Q1615 was streaming video, we breathed a sigh of relief. The issues with the pre-production demo unit didn’t occur, and image quality was high with good detail and colour fidelity, before we’d even made any adjustments.
Few tweaks are needed to ensure a consistent image, and with the image maximised for image quality the unit can deliver a very high quality stream without dropping any frames at all. If left unrestricted, the camera will use around 40Mbps (VBR) for a motion-heavy 50fps stream, or 28Mbps (VBR) for one with average levels of motion.
Latency is negligent, and there are no obvious rebuild artefacts, even with a high degree of motion in the scene.
Colour fidelity is high, and tones are produced accurately without any bias towards warmer or cooler hues. Even pastel tones, which can sometimes fade, appear correctly, and vibrant colours are well replicated without looking over-strong or artifical. Greyscale replication is also accurate, even in the challenging ranges.
Cutting back the bit-rate to a more realistic figure of 10Mbps (CBR) doesn’t display an obvious degradation in the final image. However, if you preserve image quality, frame rate will fall to around 40fps during scenes of heavy motion. Latency is still minimal. Preserving frame rate does see some rebuild artefacts appear on edges with high levels of movement, but you have to be looking for them as they’re not obvious!
With regard to the additional functionality, the feature to eliminate barrel distortion works well without giving the image an overly processed look. This feature is part of an image correction choice: the camera also delivers electronic image stabilisation (EIS), but both cannot be used simultaneously. In truth this isn’t an issue, as sites are likely to use Barrel Distortion Correction on wide angle views, and EIS in telephoto applications.
EIS also works well, and eradicates blur in images with longer range views.
With regard to the capture mode, switching to HD1080p 25fps with WDR (and switching the other way) will delete some of the system settings, and as such it’s not something you should do on a regular basis. Effectively you want to select the appropriate capture mode and stick with it.
WDR performance is impressive. Due to the time of year, low winter sun can be a real challenge for cameras, but the WDR function coped well. When in the WDR capture mode, image quality remains high, although we did spot that latency creeps up. That said, it’s still under one half of a second, and is consistent so doesn’t create any performance issues. Interestingly WDR seems to work best when filling in detail in shaded areas. Optimise the camera for the brighter parts of the scene, and it will give the best performance.
With regard to low light performance, the AXIS Q1615 features Lightfinder technology. In some previous Axis camera models there was a configuration choice between using WDR or Lightfinder. This doesn’t happen in the Q1615. Indeed, there are no Lightfinder settings in the menu, nor any mention of the technology in the User Guide. The functionality is fully automatic.
The point of Lightfinder is that it will deliver colour images, plus resolve additional detail, in low light applications. The specification for low light performance is quoted as 0.36 lux for a 50fps stream, or 0.18 lux for a 25fps stream. In low light use, there is an option to optimise the image for less noise or less motion blur.
The reality is that whilst Lightfinder technology can allow colour images to be held for longer than with standard image processing, there will always be a processing trade-off. Whether that is image noise or motion blur will be decided by your customer.
Where an end user is desperate to retain colour information, they may accept the degree of processing noise that this introduces. The image is still certainly usable, and colours are defined to a degree where they are clearly identifiable.
That said, if the degree of image degradation caused by retaining colour detail isn’t acceptable to the customer, there is still the choice to switch to a monochrome image in a typical day/night configuration. If the latter is the chosen route, it’s best to switch at around 5 lux!
Verdict
The AXIS Q1615 camera delivers high quality HD1080p video streams, and the image detail is high, motion is smooth, latency is negligible and colour fidelity is very good. As far as image quality goes, it ticks all of the boxes and is up there with the best performing HD1080p cameras Benchmark has tested to date.
Where the Q1615 steps forwards is in terms of other processing elements. HD cameras have historically lacked in terms of video processing performance, typically because much of the camera’s power was utilised to deliver video streams. However, the Q1615 has a depth of functionality which ensures that all aspects of surveillance can be addressed.
The Q1615 is indicative of a move towards ‘platform’ devices which can be supplemented with additional apps, and whilst that element fell outside of the remit of this test, it could change the way that HD cameras are specified.
