Video Test: Edge-based People Counting
Modern cameras feature increasing levels of processing power, and as a result the deployment of onboard analytics has turned from a trickle to a deluge. Where once cameras included the bare minimum in terms of IVA functionality, today the lists also include business intelligence functions such as people counting and heat mapping. This approach adds flexibility, allowing installers and integrators to enhance camera functionality dependent upon the needs of any given site. Benchmark looks at the options for edge-based people counting.
People counting offers a wide range of benefits to a number of end users. Whilst much emphasis is placed upon the retail sector when counting is considered, the applications for the technology are varied.
These range from tracking footfall in a defined area through to assessing efficiency in businesses handling members of the public or managing occupancy in line with licensing and/or site policies.
With regard to issues such as licensing and management of site conditions, compliance is a significant issue, and the implementation of people counting illustrates that this aspect of business management is being taken seriously. As such, for some sites this may be a regulatory necessity.
Accuracy figures do vary per system and are generally indicative of a worst-case scenario. With intelligent and careful installation, accuracy levels can usually be increased. For example, accuracy will be boosted if separate portals are used for access and egress, and if counting takes place at narrow pinch-points. If an attempt is made to count in a wide area where people are both entering and leaving – and inevitably meeting and loitering to chat – then the reality is that accuracy figures may decrease.
Many will argue that a camera delivering people counting functionality can effectively ‘double up’ as a surveillance camera, but this rarely the case. For effective people counting, cameras are best mounted in accordance with the instructions from the supplier of the people counting application, and this usually requires the camera to be mounted directly over the counting area, looking down. This should eradicate issues associated with perspective, and enable more accurate definition of valid targets. As such, it is best practice to not use cameras for dual purposes.
Many suppliers of people counting systems will make marketing statements that include reference to how their software will work in a range of lighting levels. Whilst there will inevitably be some truth in these statements, best practice is to ensure that the location has sufficient lighting for the camera to process a clean, noise-free real-time image with as little degradation as possible. The reality remains that counting accuracy is enhanced with clean and sharp images.
The true power of people counting comes when the user needs to view the results. The ability to not only report the data that each people counting device has captured, but to include relevant data from other devices, elevates some systems to a point where they deliver enhanced benefits to the user. If they are to realise the potential of an investment, then the data delivered by the system must fit in with their expectations.
This Benchmark test looks at edge-based counting options, with software applications and integral video analytics supplied with cameras. The test will look at installation, configuration, performance and reporting.
Axis Communications: AXIS People Counter
Axis Communications offers two people counting applications which it provides, along with a number of other third party options, for use on suitable models from its range of ACAP-compatible devices.
AXIS People Counter and AXIS People Counter 3D can be downloaded from the Axis website as demo versions. The latter 3D option is designed for use with the Axis range of stereo cameras. This test makes use of the standard AXIS People Counter version.
The application is claimed to have an accuracy of 95 per cent. It is supplied as a single.eap file. The app is model specific, and relatively few cameras which can be mounted over a counting area are supported. For legacy applications, it is worth checking if the required models are included.
AXIS People Counter has a recommended mounting height of 2.7 metres or higher, and the mounting height is roughly equivalent to the maximum area of coverage, given a 90 degree field of view.
The counting data, which is captured for two directions, can either be stored in the camera, with a maximum storage period of 90 days, or additional software can be used as part of the Axis retail suite of applications. These allow the data to be transferred to a dedicated analytics program. The choices are AXIS Store Reporter, a web-based option, or AXIS Store Data Manager which is a locally run program that enables integration of the data into third party dashboards.
As with any people counting application, the installation of the camera will be pivotal to good performance. The counting area should be free of moving objects, well lit (the counting feature is disabled if the scene is dark) and free from shadows or reflections. Also, the mounting height is critical.
A demo of the app can be downloaded from the Axis website. The people counting app was developed by Cognimatics, which is part of the Axis family, so the installation is seamless. The app is loaded via the camera’s applications menu, and a licence is obtained via the website. This will require the camera’s serial number.
Once the camera is installed as per the specification and the app loaded, the set-up can begin. Calibration involves setting the mounting height. A manual element allows the sizing for a typical single person to be set. This will only be necessary if the image has been digitally zoomed.
Fine tuning of the counting area can be achieved by adjusting its position in the image. If required, a curved counting area can be implemented.
There are a few options specific to people counting that impact on general performance. For example, users can be created that are limited to accessing the count data without being able to interact with other menu information. There is also a feature to ‘anonymise’ people that are counted with a blur. There are two choices for this: soft and hard. Be warned that the hard version turns the camera into a count-only device and removes administrator accounts. It requires a full reset if it needs to be disabled!
There is an option to fine-tune the count sensitivity. It is recommended that some testing is carried out to ensure that the accuracy figure falls at around 95 per cent. The process is straightforward, but will take some time if footfall is light.
It is worth noting that when tweaking the app it appears to stop working on occasions. However, this isn’t the case and it sometimes appears to need a short period to stabilise performance.
Data can be viewed in tabular form or as a graph. The reality is that few users will want to view the count data via the camera’s web server, but with options for further integration the figures can be integrated into a third party interface.
Bosch Security: Essential Video Analytics
Bosch Security offers two versions of its video analytics engine as an integral feature on the company’s cameras. Dinion cameras in the 7000 and 8000 series include Intelligent Video Analytics, while devices in the more cost-effective 4000, 5000 and 6000 series cameras include Essential Video Analytics. Both are included as a standard feature and are licence-free.
The package allows two types of counting: counting based upon crossing a virtual line, and counting into an area with a notification created once a predefined occupancy is achieved.
Where more complex needs are required, up to eight independent analytics rules can be created. There are a depth of calibration options to enhance accuracy.
Bosch Security no longer offers documentation or utilities with its devices. The quick start guide does include a URL for the download area, and to be fair the various utilities are easy to find. The guide recommends downloading Bosch Video Client, Video Security Client and Configuration Manager.
With regards to installation, the two important downloads are the IP Helper utility and the MPEG-ActiveX element. The first finds connected cameras (even if on a different network segment) and allows the IP address to be configured. The latter is required to allow streaming video to be viewed via a browser for initial set up.
With regard to the video analytics in general, it is worth mentioning the Configuration Manager software. Depending upon the specific model of camera, this may or may not be necessary for set-up.
When Bosch first started to include video analytics, the functionality was licensed. To keep the interface simple, set-up was carried out via a separate software tool. This was clearly explained via the documentation.
Now the integral video analytics is included as standard, and set-up of the analytics tends to be achieved through the camera’s menus. This was the case with our test unit, as well as a range of Bosch devices using both Essential Video Analytics or Intelligent Video Analytics in tests over the last year.
However, we have also seen a few models where the video analytics set-up options do not appear, and as a result the Configuration Manager has to be used. This isn’t a great hardship and the tool works well and is simple to use. It’s more a case of being aware of the solution should the situation arise.
The creation of a counting rule is carried out via the alarm menus and specifically the VCA screen. The analytic method is selected (in this case Essential Video Analytics) and a separate set-up window opens once the Configure option is selected.
It is important to ensure that the camera is correctly calibrated for accurate counting. This isn’t something that you’ll be able to second-guess, and the lack of easy-to-find documentation does impact on the installation and configuration time. We tried to find a comprehensive manual with no luck, and eventually located guidance for setting up people counting on the Bosch US website.
Without the guidance document it is a bit of a challenge to get the camera properly configured, and sadly its one of the issues that is increasingly common when manufacturers make their customers search for documents and utilities that should be included as standard. For some installers and integrators, the lack of support materials might be the deciding factor when selecting which product to opt for.
Calibration for people counting is carried out via the video analytics configuration menu, and the camera position is established via the camera positioning menu. In the Metadata Generation menu there is a tab marked Tracking, and the 3D people tracking model needs to be selected with appropriate values entered.
To establish the count line, clicking on the New button activates a blank rule and the first task is to select the type of detection. There are two options for counting: Counter and Occupancy. The first counts people passing over a virtual line, while the second counts people in an area.
The main focus of the test is for line-cross counting. To configure this the first task is to create a new line. There are two options. Either select New Line from the drop down menu (this inserts a single line with draggable nodes) or simply click within the image to add nodes. The latter option allows a multi-segmented line to be created.
The next stage is to set properties for the line. These include debounce time, direction (forward, backward or any) and intersection trigger (object base point or object centre).
There is an option to set a count limit, and when reached this will either stop the counting process or reset the counter. Alternatively, the analytics can be configured to create an alert once an overflow situation occurs.
As the camera will have been calibrated for 3D people tracking, filtering by class only has the upright person option. The others (bicycle, car or truck) will be greyed out.
The next task is to click on a highlighted object in the viewed scene, and the parameters of that can then be acquired. There is a further facility to tweak the filtering if required.
As expected from functionality that needs careful setting up, the people counting works well, and with regards to accuracy it is in the ball-park of 95-96 per cent.
Reporting options are flexible, but as with set-up you will need some guidance on configurations because it’s not straightforward. If anything, the Bosch option does reward the effort of configuration with a stable and flexible proposition, but the manufacturer could enhance this by offering clear and easily available instructions.
Hanwha Techwin: Wisenet X
Wisenet X is Hanwha Techwin’s flagship camera range and incorporates high quality imaging with a depth of features and functions. Based on a high-level processing platform, the 2 megapixel and 5 megapixel devices include a range of video analytics, including people counting.
Based on the Wisenet 5 chipset, the camera includes a variety of video and audio analytics, including business intelligence options in the form of people counting, heat mapping and queue management.
Other video analytics include line cross detection, zone enter and exit, object appear and disappear, loitering, face detection and tamper protection. Audio analytics are also included, as is sound classification which can differentiate between screams, breaking glass, gun shots and explosions.
As with the other devices, the camera should be mounted above the count area with a bird’s eye view for enhanced accuracy.
With regard to people counting, two count lines can be set in each scene. The camera requires calibration to ensure the accuracy is consistent. People counting data is reset at midnight every day, and reports can be created to show historical count data.
The Wisenet X range of cameras are supplied with a full manual in PDF format and the IP Installer utility, which is used to discover cameras on the network and configure the network details. The utility works well, and simplifies initial set-up.
It must be said that the menu structure within the Wisenet X range is clean and intuitive, and whilst it may at times seem to be too simple, this is often due to the fact that it is well structured.
The people counting configurations are not in the Events or Analytics menus where most manufacturers put them, but reside in the Statistics menu along with heat mapping and queue management.
The people counting menu has two sub-menus: Search and Set-up. The first is used to set how reports are managed and delivered. The latter involves the creation of the actual counting mechanism.
Although the process is simple, there is also a prompt under the reference image that ensures each step is covered. If things don’t seem to be working, you can see why!
With people counting enabled via a simple tick-box, the count lines are then added. Two lines can be supported if required. It is worth noting that each line is single between two nodes; segmented lines are not supported. Also, it initially appears that each line is only capable of counting in one direction, but this is not the case. A single direction can be set, which records as ‘In’. However, a line cross against the direction of that arrow counts as an ‘Out’ read. If you set up both lines in order to create an ‘in/out’ count, as we initially did, you will receive duplicate counts which can be confusing.
With the lines set and named, the next task is to decide how the reports are to be handled. There is an on-screen display but this is reset every 24 hours, plus it involves logging in to the camera’s menus to view it.
Reports can be scheduled on a daily or weekly basis and files can either be sent in an .xlsx or .txt format. Delivery is via email or FTP.
Exclude areas can be configured should they be required. Up to four are supported and these prevent any line crosses in the defined area to not implement a count.
The final task is to adjust the calibration of the camera. This setting is applied to both people counting and heat mapping. A virtual box is presented in the on-screen display and this is dragged over a person to establish their size as they pass through the count zone. This is simple and intuitive, making it quick and easy to set up.
all steps are carried out correctly, the counting works well and accuracy was on a par with the other units tested, at around 95 per cent. Whilst reports are limited to the transmission of a file, this will allow users to add the data to other systems that important standard file formats (which most dash-board type business analytics interfaces do).
AXIS People Counter offers a decent level of accuracy and is simple to install and configure. Unlike the other people counting functions on test, it does require an additional licence, and if off-camera reporting is required (as it probably will be) an add-on software element will also need to be purchased. These additional costs need to be factored in when assessing the application, but if it meets budget it will provide a good level of performance. As such, it is recommended.
The Bosch Essential Video Analytics package is licence-free, and allows a good degree of calibration to maximise accuracy. The options for deployment are flexible, and that will appeal to a number of applications where the use of people-counting will be of benefit to those outside the security department.
The downside is that the set-up is not really intuitive and we had to search for information that explained the configuration, eventually using some out-of-date documents from the Bosch US website. Despite this, with the proviso that documentation is supplied, it is recommended.
Hanwha Techwin’s Wisenet X camera range does have a number of features and functions, and these are well implemented. With regard to people counting, the set-up is straightforward and quick, and the process is intuitive. Even camera calibration has been simplified, and as a result this will appeal to many who are seeking people counting in small and medium-sized enterprises.
While the reporting mechanism is relatively simple, it does allow delivery of data files in common formats which can be imported into other dashboards if required. Where a basic solution is required, it has to be recommended with the proviso that it won’t be the most suitable option if the user runs a multi-site organisation and wants a business-wide option.