10  Description — FLIR Screen-EST‎

    The FLIR Screen-EST application consists of two windows:
  • The operator window is used for setup, control, and monitoring. For more information, see section 10.2 Operator window .
  • The visitor window is what the screened person sees. For more information, see section 9 Visitor — Screening procedure .
For configuration of FLIR Screen-EST, see section 6.4 Optional: Customize FLIR Screen-EST‎ .

10.1  Start application

You start the FLIR Screen-EST application from the Start menu or by double-tapping the desktop icon.

10.2  Operator window

The operator window has one main page with two tabs, Library and Live, and a Settings page.

10.2.1  Library tab

The Library tab shows the File Explorer. Here you can navigate to any folder with saved images.
When you click a folder, the images in that folder are presented in the center pane. When you click an image in the center pane, information about that image is shown in the pane to the right.
Clicking the Library tab displays a toolbar, with options for settings, user manual, support, license, and more.
Graphic

10.2.1.1  User manual

To access the FLIR Screen-EST user manual, select User manual on the Library page toolbar or go to http://support.flir.com/resources/est .

10.2.2  Live tab

The Live tab is where you initiate and monitor the screening.
The image below shows what the user interface looks like when a camera is connected.
Graphic
  1. Discovery pane
    This pane displays the available cameras. Find the FLIR camera and use the button to the right to connect.
    When the Auto-reconnect check box is selected, the camera connects automatically next time FLIR Screen-EST starts.
  2. Camera capture pane
    This pane includes buttons for camera control, e.g. autofocus.
  3. Events pane
    This pane displays all events and operations performed to a connected camera. Use the buttons to clear or save the logs to a file.
  4. Camera image pane
    The live thermal and visual images from the camera is displayed here.
    The system is looking for faces in a part of the image which is called the region-of-interest. The dotted box on the images here indicates the region-of-interest for the face detection. The size of the region-of-interest box is defined by a setting (see section 10.3.1 Face detection tab ). You can change the size of the box by a drag-and-drop operation here.
  5. Face detection pane
    • When the Enable tracking check box is selected, the face detection and screening functionality is enabled. To temporarily stop the screening, clear the check box.
    • The Alignment data controls are used to align the images from the thermal and visual cameras. When the Auto-alignment check box is selected, the alignment is done automatically. If the images for some reason are not aligned, first clear the Auto-alignment check box and then align the images manually using the PanX and PanY controls.
    • Moving averages: Value shows the current average. Samples count is the number of samples included in the average calculation. Status shows the sampling status; red when there are no samples, green when the system is adding samples to the average calculation. Hovering over the Value/Samples count/Status area displays a reset button. Click the button to reset the average value.
    • The Detection status section displays status information and screening results.
      • Not available: No face detected.
      • Normal: Screening result; normal temperature.
      • Abnormally high: Screening result; elevated temperature.
      • Glasses: Eyeglasses detected.
      • Bad pose: Visitor face is not straight in front of the camera.
      • Too far: Visitor face is too far from the camera.
      • Too close: Visitor face is too close to the camera.
      • Too many: More than one face detected.
      • Waiting for exit: System is waiting for the screened person to leave the screening station.
      • Below skin temperature: Measured temperature is below the Skin minimum temperature setting (see section 10.3.1 Face detection tab ).
      • Above skin temperature: Measured temperature is above the Skin maximum temperature setting (see section 10.3.1 Face detection tab ).
      When a screening result is displayed, Face 1 shows the measured temperature.
      When the Required manual reset check box is cleared, alarms are automatically reset when the screened person moves away from the camera. When the Required manual reset check box is selected, the operator must manually reset alarms by clicking inside the red Detection status box.
      Graphic
Clicking the Live tab displays a toolbar, with options for connection, settings, camera control, and events.
Graphic

10.3  Settings page

You access the Settings page via the toolbar on the Library and Live tabs in the operator window.
To exit the Settings page, click Close at the bottom right of the page.

10.3.1  Face detection tab

    Moving average
  • The Default samples count is the number of samples that are included in the average calculation.
  • When the Reset moving average after specified time check box is selected, the system automatically resets the moving average when the specified time has elapsed since the last screening. When the system starts to build up a new moving average, the first measurement will be evaluated based on the Temperature after reset value. For more information, see section 10.4.3.1 Reset of moving average .
    Face detection status
  • The screening algorithm only evaluates temperatures between the Skin maximum temperature and Skin minimum temperature values. It is recommended to use the default values.
  • There will be an alarm if the measured temperature is more than the sum of the moving average and the Allowed deviation value. Setting a low value will detect smaller elevations in skin temperatures, but it will also generate more false alarms. With a high value, there is a risk of missing people with elevated skin temperatures.
    Detector type
    The application can use either the thermal data stream or the visual data stream for face detection and definition of measurement area.
  • Use the Detector type list to select thermal or visual face detection.
    Image settings
    These settings apply to the live camera images in the operator window.
  • Select the Mirror image check boxes to mirror (flip) the image.
  • Use the Image orientation list to select portrait or landscape orientation.
    Region of interest
    The system is looking for faces in a part of the image which is called the region-of-interest. On the Live page, the dotted box indicates the region-of-interest for the face detection.
  • The Initial size values define the size of the region-of-interest box (in percentage of the image).

10.3.2  User screen tab

The settings on the User screen tab apply to the visitor window.
    Custom status messages
  • Use these fields to change the status messages. You may, for example, want to translate the messages to your local language.
    Font size
  • Select the font size for the status messages.
    Visibility settings
  • Use the Screen orientation list to select portrait or landscape orientation.
  • Select the Show secondary image check box to display both thermal and visual video.
  • Use the Show hats/glasses/masks check boxes to select what symbols to display.
  • Select the Enable animations check box to have a moving blue line in the visitor window, indicating that the system is in operation.
  • Use the Swap video streams check box to select the display of thermal or visual video in the main image.

10.3.3  Output tab

FLIR Screen-EST can be configured to save images and data when an elevated skin temperature is detected. It is the responsibility of your company to handle any saved images and data in accordance with applicable local data protection laws.
    Snapshot options
  • When the Save dual snapshot separately check box is selected, a separate visual image will be saved in addition to the combined thermal and visual image.
    Output options
  • When the Open output folder after saving snapshot check box is selected, the folder with the saved image will open when the saving is completed.
  • To change the file path to the folder where you want to store saved images, click Browse and then select the folder.
    Alarm
  • When the Log alarms to output folder check box is selected, an image (combined thermal and visual image) and a data file (*.csv) is automatically saved when an elevated skin temperature is detected. By default, this check box is cleared and no images are saved automatically.
  • When the Use sound alarm check box is selected, there will be a sound when an elevated temperature is detected.
    Digital output
    The screening result can trigger an external device, such as a gate, lights, or a siren, connected to the digital I/O connector on the camera.
    Cameras that support multiple digital outputs will send a signal on digital output 1 for a positive condition (Elevated temperature) and a signal on digital output 2 for a negative condition (Normal temperature).
  • When the Enable digital output check box is selected, a digital pulse will be output after a Normal temperature or Elevated temperature screening result.
  • Use the Elevated temperature signal’s timespan and Normal temperature signal’s timespan fields to define the time (in milliseconds) that the digital output is enabled when a positive/negative result is detected by the camera. Set the value to 0 milliseconds to make the output enabled as long as a positive/negative condition is met.

10.3.4  Webhooks tab

The Webhooks tab is used to control the webhooks functionality. For more information, see section 10.5.2 Webhooks .
  • Use the button to activate/deactivate webhooks. The settings can only be changed when webhooks is inactive (red Off).
  • Select the Run on application start check box to activate webhooks automatically when the FLIR Screen-EST starts.
  • Use the Computer port field to specify the path port on which FLIR Screen-EST shall listen to incoming POST requests.
  • Use the URL fields to specify the URL for the callbacks.
    The callback URL format is:
    http://address:port/api/callback/#
    where # = alarm/pass/misreading/ready/waiting/error/standby
    • Default alarm URL (alarm): The screening result is Elevated temperature.
    • Default no elevated skin temperature URL (pass): The screening result is Normal temperature.
    • Default misreading URL (misreading): There is no successful screening result within the time limit set by the Misreading timeout setting.
    • Default system’s readiness URL (ready): The system is ready to perform a screening.
    • Default system awaiting URL (waiting): The system is waiting for a person to screen.
    • Default system error URL (error): System error, e.g. no camera is connected or not enough samples have been collected.
    • Default system stand-by URL (standby): The screening is deactivated and the system closed message is displayed in the visitor window.
  • Use the Misreading timeout field to set the time limit for a successful screening result (normal or alarm).

10.3.5  General tab

    General options
  • When the Start application on system start-up check box is selected, FLIR Screen-EST will start automatically when the device (computer or tablet) starts up.
  • When the Enable application monitoring check box is selected, FLIR Screen-EST will restart automatically after an unexpected crash or if the application is not responding.
  • Click Factory default settings to reset the application to factory settings. FLIR Screen-EST will restart to apply the new settings.
  • Click Clear cache to delete locally cached content. FLIR Screen-EST will restart to apply the new settings.
  • Click Settings panel password to protect the Settings page with a password. This opens a dialog box. Select the Protect settings panel with password check box and enter the password.

10.3.6  Updates tab

Select how you want to manage updates of the FLIR Screen-EST.
When the Check if updates are available check box is selected, a check for updates will automatically be performed every time the application is started.
When the Prompt to install updates check box is selected, you will be asked to install any available updates. The Check if updates are available option must also be enabled.
If updates need to be downloaded via a proxy service, an additional configuration is needed. In the Proxy settings dialog box, select the Use proxy check box, and then enter the requested information. Click OK to save.

10.3.7  Theme tab

Change the theme of the user interface. FLIR Screen-EST will restart to apply the new settings.

10.3.8  File explorer tab

Select if you want to show hidden files and display folder previews.

10.3.9  Editor tab

Change the file path to the folder where your custom palettes are located.

10.3.10  Regional settings tab

Select the language and units to be used in the user interface. FLIR Screen-EST will restart to apply the new settings.

10.4  Working principles

FLIR Screen-EST system uses face detection and measures the temperature at the tear duct, since that has been demonstrated to be a robust measurement point. The system uses a relative screening method, comparing subject temperatures to a dynamic baseline of measured skin temperatures.

10.4.1  Face detection and measurement area

FLIR Screen-EST can use either the thermal data stream or the visual data stream for face detection and definition of measurement area.
Thermal detection
The system finds the face and locates the tear duct using FLIR thermal and AI technology. The thermal camera then measures the temperature at the tear duct.
Visual detection
The system finds the face using face detection on the visual data stream. A box representing the measurement area is drawn and adjusted to cover the face. The thermal camera finds and measures the hottest spot in the measurement box, which usually would be the tear duct.
    Thermal detection has the following advantages compared to visual detection:
  • Ensures measurement at the tear duct.
  • Works in any light condition, also when it is dark.
  • Makes it harder to fool the system, e.g. by faking a face with a photo.
If the ambient temperature at the screening station is high (not recommended), the visual detection may perform better. The thermal detection can have difficulty distinguishing faces from a warm background.

10.4.2  Relative screening method

The system uses a relative temperature screening method, with a moving average of measured skin temperatures as reference. This allows the screening algorithm to compensate for changes in conditions over time.
The measured temperature is compared to the sum of the moving average and a configurable allowed deviation. The elevated temperature alarm will trigger if the measured temperature is above the alarm limit. The alarm limit is the sum of the moving average and the allowed deviation.

10.4.3  Moving average

The moving average is calculated based on a number of previously registered temperature measurement samples. The number of samples is configurable.
At the beginning of a new screening session, there are no previous samples and the system must start to build up the baseline for the moving average. This is done as part of the normal screening procedure. For the very first screened person, there will be no analysis. The first measured temperature will always be added to the average calculation (if it is within the operating range, see section 10.4.4 Operating range ) and the screening result will always be normal (green).
To prevent an elevated temperature from being used as the starting reference, it is recommended to make sure the first screened person has a non-elevated temperature.

10.4.3.1  Reset of moving average

If there has been a long time since the last screening, the moving average may not be at the correct level. For example, after a long night the moving average may still be at a high level, based on the screenings from the afternoon or evening, but persons arriving in the morning are cold. Before the moving average has adapted to the new conditions, there is a risk for a false negative; that is, a Normal screening result even though the person actually has an elevated temperature.
One way of limiting the risk of false negatives is to reset the moving average after a long period of non-screening. The system will then start to build up a new moving average.
If the operator manually resets the moving average, the normal build-up procedure applies and there will be no analysis of the first measurement. The operator should make sure that the first screened person has a non-elevated temperature.
It is possible to enable a function that automatically resets the moving average after a specified time of non-screening. Since the moving average is reset without any operator interaction, there is no control over the first screened person. For that reason, a special build-up procedure applies after an automatic reset of the moving average. In this special case, also the first measurement will be analyzed and the alarm will trigger if the measured temperature is above the sum of a configurable fixed temperature and the allowed deviation.

10.4.4  Operating range

If the spread of values in a data set is large, the average will be difficult to use for evaluation of individual values. For that reason, the screening algorithm will only work with temperatures that are within a certain temperature range. If the measured temperature is outside this range, the system will display a “Too cold/warm” message and there will be no further analysis.
If the system displays a “Too cold/warm” message, the visitor should wait a few minutes to allow the skin temperature to acclimatize to the temperature at the screening station and then try the screening again.
The temperature range is defined by a maximum and minimum temperature limit, which is possible to change by settings. It is recommended to use the default values. The settings should only be changed if you experience problems and understand the consequences.

10.4.4.1  All visitors from cold environment

In a situation where all visitors come directly from a cold outdoor environment, without possibility to adapt to the indoor temperature, the screening flow may be disturbed by many “Too cold” messages.
By changing the minimum temperature setting to a lower value, there will be fewer “Too cold” messages. Since all visitors come from the same ambient temperature, the measured skin temperatures will still be comparable.

10.4.4.2  Mixed flow – both cold and warm

If the visitors come both from a cold outdoor environment and from a warm indoor environment, you need to be careful about changing the minimum temperature setting.
Persons entering a building from windy and snowy weather will have a lower skin temperature, regardless of their body temperature. The cold exposure could reduce the skin temperature of someone with an elevated temperature low enough to fall under the alarm limit.
If people coming directly from a cold environment are not stopped by a “Too cold” message, they may not have time to adapt their temperature to the indoor temperature before the screening algorithm performs the evaluation. This means there is a risk that people with an elevated temperature pass the screening, since the skin temperature of their cold faces may be below the alarm limit.
If people coming directly from a cold environment are allowed to adapt their temperature to the indoor temperature before the evaluation, only persons with a normal temperature will pass the screening and there will be a screening alarm for persons with an elevated temperature.

10.5  Integration with external systems

    There are two ways to integrate FLIR Screen-EST with an external system:
  • Digital output.
  • Webhooks.

10.5.1  Digital output

A basic level of integration is possible if the FLIR camera has a digital I/O connector.
  1. Connect an external device such as a gate, lights, or a siren to the digital I/O connector of the camera.
  2. Configure FLIR Screen-EST to trigger a digital pulse depending on the screening result; Normal temperature or Elevated temperature. For digital output settings, see section 10.3.3 Output tab .

10.5.2  Webhooks

Webhooks is a method for HTTP communication between different systems. By using webhooks, FLIR Screen-EST can be controlled by a third-party system. As an example, you can include FLIR Screen-EST screening in your access control system.
    General workflow for a third-party access control system with FLIR Screen-EST screening:
  1. The visitor starts the sign-in process through the access control system.
  2. The access control system prompts the visitor to perform a screening and sends a Start command to FLIR Screen-EST.
  3. The FLIR Screen-EST displays live images in the visitor window, measures and analyzes the temperature, and displays a screening result in the visitor window.
  4. FLIR Screen-EST sends the screening result, Normal temperature or Elevated temperature, to the access control system.
    If there is no screening result within a specified time limit, a Misreading response is sent instead.
  5. The access control system sends a Sleep command to FLIR Screen-EST.
  6. The screening functionality in FLIR Screen-EST is deactivated and the visitor window displays the system closed screen.

10.5.2.1  POST requests to FLIR Screen-EST‎

FLIR Screen-EST is configured to listen for POST requests on the following paths:
Start request: http://workstationAddress:port/screenest/start
Sleep request: http://workstationAddress:port/screenest/sleep
    where:
  • workstationAddress can be the local IP (localhost) or an external IP address.
  • The path port must be the same as the computer port specified in the FLIR Screen-EST settings, see section 10.3.4 Webhooks tab .

10.5.2.2  Callbacks from FLIR Screen-EST‎

After receiving a Start/Sleep POST request, FLIR Screen-EST will make a callback on the address defined in the POST request body. If the callback address is missing in the request, the address specified in the FLIR Screen-EST settings will be used.
    This means you can specify the callback address (URL) in two ways:
  • Send the URL via the POST request body.
  • Specify the URL in the FLIR Screen-EST settings, see section 10.3.4 Webhooks tab .
The callback URL format is:
http://address:port/api/callback/#
where # = alarm/pass/misreading/ready/waiting/error/standby

10.5.2.3  Events after a Start request

When FLIR Screen-EST receives a Start request, the following happens:
  • If FLIR Screen-EST is not ready for screening, it responds with an error callback.
  • If FLIR Screen-EST is ready for screening, the following happens:
    1. In the operator window, the Enable tracking check box is selected.
      The visitor window displays live images.
    2. FLIR Screen-EST sends a ready callback, indicating that the system is ready for screening.
    3. FLIR Screen-EST sends a waiting callback, indicating that the system is waiting for a person to screen.
    4. FLIR Screen-EST sends one of the following callbacks:
      • pass — if the screening result is Normal temperature.
      • alarm — if the screening result is Elevated temperature.
      • misread — if there is no successful screening result within the specified time limit.

10.5.2.4  Events after a Sleep request

    When FLIR Screen-EST receives a Sleep request, the following happens:
  1. In the operator window, the Enable tracking check box is cleared.
    The visitor window displays the system closed screen.
  2. FLIR Screen-EST sends a standby callback.

10.5.2.5  Webhooks settings

For webhooks settings, see section 10.3.4 Webhooks tab .

10.5.2.6  Configurations for external system outside localhost

For FLIR Screen-EST to receive incoming POST requests and return callbacks from outside the localhost, you may need to configure the firewall and port settings of the computer where FLIR Screen-EST is installed.