Road-testing The Axis Lightfinder 1602
Posted by Security Electronics and Networks | @Articles Product Reviews | April 9, 2012, 7:00am AEST
IT’S always fun getting a look at a new camera – especially when that camera is designed specifically to offer a clear performance advantage certain to delight integrators and end users. Given this new Axis 1602 tackles what has long been seen as the Achilles heel of IP cameras head on, I’m pretty keen to get a look-see.
Turning up at the Axis office at Castle Hill in Sydney I’m welcomed into an inner office that’s well away from external windows. The boys from Axis have taped black nylon over all windows to block out stray sunlight and ambient fluorescent lights from adjacent walkways.
The new 1602 is standing on the desk in the middle of the room in front of me. Bear in mind, we are testing the internally-rated 1602, not the externally rated 1602-E. I look curiously at the camera. This is unmistakably an Axis product with the general look of that benchmark Q1755 720p unit the company released back in 2008. There are key differences. This camera is much sleeker towards the rear, though when I pick it up there’s the same weighty feel. Turning the camera over in my hands I find no superfluous ports or controls of any kind. You have an RJ-45 network port and you have standard-type audio ports.
This 1602 with the ARTPEC-4 chipset is the vanguard of the Lightfinder range. There will be other models in higher resolution starting at 720p
I look for some sign the 1602 can see in the dark as I take a few photos of the unit – something in the lens, some subtle variation of design, even a distinguishing mark of some kind on the case. There’s nothing out of the ordinary to be seen here. What’s important is under the surface – it’s the new ARTPEC-4 chipset, specifically designed to improve light sensitivity and to lower noise levels. Cutting noise levels is vital when it comes to bandwidth consumption and storage demands in low light.
There’s no doubt ARTPEC-4 is the pointy end of Axis’ Lightfinder technology. Lightfinder is firmware that benefits from the new chipset’s light sensitivity and leverages enhanced processing from a grunty new CPU with a higher clock speed to do the heavy lifting of filtering and sharpening image streams post-capture in real time. Another part of ARTPEC-4 is a co-processor to drive comprehensive video analytics – it’s all very nice stuff from the folks at Axis.
“This 1602 with the ARTPEC-4 chipset is the vanguard of this Lightfinder range there will be other models in higher resolutions starting at 720p,” Axis’ pre-sales engineer Chris Tangsilsat explains to me.
“The Q1602 is essentially a combination of 2 components, the first being a 1.3MP image sensor. Even though the camera runs in 4CIF or D1 resolution we actually use this 1.3MP sensor in order to amplify the light that falls onto each receptor. For our analytics to work effectively on the backend post-capture, we need a sensor that is twice the resolution of what we are going to be pushing out.
“The other part of the processing is the ARTPEC-4 chipset which employs its own light enhancing algorithm in the backend.”
Taking the test
Tangsilsat says he plans to the undertake the test in 3 stages – with lights on and the door open in Stage 1, with lights off and the door open in stage 2 and with lights off and the door closed in Stage 3. Stage 3 is the ultimate test.
The test room has light walls and there’s a banner with a little colour and a bright red Christmas card positioned in a corner so as to provide a colour reference when the camera cuts to black and white. We start by sitting down at a laptop on which the test images are being viewed.
Tangsilsat explains that this camera features a new firmware version 5.40 which allows users to tweak settings. There’s a setting for normal light conditions and a range of different exposure settings for low light. The software we are using to view camera scenes is a very tidy affair with a significant amount of control integrated into it. These include image settings, events and analytics.
“You can see that under the normal light setting I have the camera at low noise priority, maximum gain and maximum shutter speed. Under low light you can independently use another profile like low motion blur or set the maximum shutter speed to 1/25.
“This matters because I think one of the biggest issues with cameras today is that when you get to that point when you go below one lux, while the image retains colour, because the shutter speed slows down, you start to get motion blur effect.
If you compare the 1602 to another 4CIF IP camera running the same frame rate and the same compression, you might see 1-1.5MB bandwidth on the other camera but the 1602’s image is so clean that bandwidth consumption drops down to 140kbps.
“Just for the record, you can see that for our test I have left the camera on its factory default image settings so there’s been no tweaking. The standard lens is 2.8-8mm focal length lens which is ideal for typical applications.”
Importantly from the point of view of objective testing, Tanglisat starts the test off with a light measurement in the middle of the room with the lights on and the door open. He finds from 100 to 140 lux. We take a look at the images on-screen.
“You’ll notice under normal lighting conditions the image is very clean, there’s no noise, no pixellation,” Tangsilsat says. “Importantly, if you compare the 1602 to another 4CIF IP camera running the same frame rate and the same compression, you might see 1-1.5MB bandwidth on the other camera but the 1602’s image is so clean that bandwidth consumption drops down to 140kbps.
“So – let’s see what this camera can do, first with the door open and the lights off,” Tangsilsat says switching off the light and pulling out the light meter. “With the lights off I have about 0.05 lux – definitely well below one lux. Typically 0.05 lux is the minimum scene illumination of most day night cameras operating in black and white.
“Looking at the screen view you can see the 1602 still retains colour at this level and if you move your hand around you’ll see the image is quite solid – there’s no motion blur.”
I look at the image while Tangsilsat stands in the field of view and moves his arms. There might be the tiniest fraction of delay but it’s near perfect and I’m not certain I’m seeing any. At this point I turn the laptop screen away from the target area in order to minimise the amount of stray light. The image is not really altered by this expedient at all.
It’s rather strange I think to myself, but looking at this scene it’s almost as if there’s strong backlight coming in through the door. Importantly, while there’s whiteness in the entryway where light is entering, it’s not spilling into rest of the scene.
Next, Tangsilsat gets up and shuts the door. Again he pulls out the light meter and it registers a measly 0.001 lux. The 1602 does not much seem to care. Tangsilsat has a black shirt on and the camera is picking him up at say, 2.5-3m with complete definition of form and with a surprising level of face recognition. With my lighter shirt I’m positively glowing in the dark. I turn the monitor away from the target area again and I can see the camera works in what is practically complete darkness. Again, I see no latency, though there’s some grain in the image at 0.001 lux as you’d expect there to be.
Tangsilsat says that in these sorts of conditions with other cameras you would need an IR illuminator and I can’t argue. I’m completely unable to view any detail in the corners of the room.
“You also find the dynamic range is not bad as well – with you in the foreground, well illuminated and myself in the background in dark clothing, and you can still get clear facial ID off me,” he explains.
Now Tangsilsat points the camera into the corner where the poster and Christmas card are. I can see very little in the corner, just the faintest of shapes in the upper half of the scene, shades of darkness and no colour despite my having being in room long enough for my eyes to have adjusted to the low light.
On the screen I perceive something small and rectangular sitting on top of a low table all of which is perfectly invisible to the naked eye. I go over and it’s the Christmas card. The camera can see while we are blind in these conditions. There’s no doubt at all that performance is extremely good – it’s better than any unassisted analogue camera could ever be.
Having viewed the images in low light, Tangsilsat demonstrates the key element of any low light IP camera’s performance – low bandwidth. The importance of low bandwidth here cannot be overstated given the impact on network performance and storage demand. Again, the lights go off but the door stays open.
“You can see in H.264 at full frame rate the 1602 is only using 200-300Kbps bandwidth at 0.05 lux,” he says. “This is important because with competitor’s cameras the extra noise in the image can see bandwidth jump up to 2.5Mb even with no movement in a scene.”
Now, with door closed and the lights off I can again see there is some graininess/noise in the image and as a result bandwidth jumps to 1.7Mb in a scene with movement – in this case Tangsilsat and I moving in front of the camera. When we stand still, bandwidth is 1.3Mb at full frame rate in H.264. It would be less bandwidth in a darker external scene, particularly given we are both right in front of the camera and I am wearing that light shirt. In an ordinary scene the depth of field would be significantly greater, too.
“If I drop the frame rate to 12 frames per second the bandwidth drops to 136kbps with no movement in the scene,” Tangsilsat explains. “That’s fluid enough in terms of frame rate to clearly show what is going on.”
When we both move about in front of the camera at 12ips this jumps up to 450kbps but that’s extremely good under these conditions. The image is quite sharp for something running at 4CIF in almost complete darkness. Low bandwidth profiles like this make the camera ideal for 3G or 4G wireless connections.
Tanglisat backs up our test by showing me some images of the camera installed in large street applications with very little ambient lighting. Here the camera really shows its true colours. Scrounging every scrap of light and working hard on the enhancement, these images are surprisingly bright, colourful and crisp.
Features of the 1602
The indoor AXIS Q1602 and the outdoor-ready AXIS Q1602 can deliver multiple, individually configurable H.264 and Motion JPEG video streams simultaneously. This built-in multiple streaming means that video streams can be optimized individually giving increased flexibility and power costs.
The camera’s other features include day and night functionality, varifocal lens, remote back focus and support for two-way audio. The IP66-rated Axis Q1602/-E, which comes with a wall mount bracket and a sunshield, is protected from dust, rain, snow and sun, and can operate in temperatures from -40 °C to 50°C (-40 °F to 122 °F).
According to Tangsilsat, cost is about 7-10 per cent premium over standard cameras in the range with the same specification. It’s good value considering these cameras are specifically designed for a low-light environment where typically there’s the added expense of an IR illuminator.
“Same as our other cameras, the 1602 has remote backfocus, and there’s downloading of analytics like people tracking, motion detection, cross-wire detection, virtual fence analytics and traffic flow analytics. All you are doing is loading them up as application modules,” Tangsilsat explains.
“And when it comes to events we can do action rules. One of the nice events you can set up with this particular unit is to upload an application called cross-line detection so the unit can detect a person who has crossed a virtual fence. When that event triggers, the camera can generate a command line to tell a PTZ on the same network to go to the relevant preset. It’s like a camera-to-camera communication and there’s no need to go back to a server for verification.”
Recording-wise when saving footage to a 32GB SD card, you find your recording list in Axis Camera Station software. From there you can pick and play, download, delete and export footage. A neat alternative is to retrieve footage by ftp – all Axis cameras have a built-in ftp server you can log onto. You then manually browse the SD card folder and do a copy and paste action. All this functionality really highlights the fact this camera is designed to run independently as a standalone VMS. And obviously, if you want to integrate the camera into practically any third party VMS, Axis is the perfect choice.
“All our cameras can deliver 6 streams at full frame rate while maintaining H.264. If you need more streams than this all our cameras support multicasting across the network,” Tangsilsat explains. “We are also ONVIF compliant and support standard network security protocols, so the camera has the ability to generate and import a self-signed certificate – that means 128-bit data encryption.
“And when it comes to ports and devices, this model has one input and one output relay port so it can be integrated into anything with an on/off switch.”
AXIS Q1602 and 1602-E network cameras are supported by Axis Camera Station management software. In addition, the cameras include support for Axis Camera Application Platform and Axis Video Hosting System (AVHS), with single click camera connection for managing video monitoring services over the Internet.
Obviously not every camera location needs low light sensitivity but there’s no doubt that in almost every application you find multiple tricky locations that need a camera like this – server rooms, car parks, external entrances and stairwells.
Heading home from the test drive I can’t help feeling that with the new 1602 and 1602/-E, IP video’s pioneering manufacturer has done it again. Best of all, knowing Axis, it’s only a matter of time before the company’s powerful Lightfinder technology spreads across the entire product range.