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SLN-VIZNAS-IOT User Guide, Rev. 1.1, 10/2020
NXP Semiconductors
Figure 21: On-screen Info for Recognized Face
In this example, the on-screen info reflects information about the face being recognized.
As shown in the screenshot, the face has been recognized with 95% similarity to the
matching face in the internal database (hence
“sim: 95”
) and has passed both the RGB
and IR liveness checks (hence
“rgbLive: 1”
and
“irLive: 1”
).
NOTE
: The “front face check” is only performed by the inference engine for faces being registered
to ensure that no face gets registered that it is improperly angled towards the camera. For this
reason, the “front” value will not change unless a registration is being performed.
2.2.6 (Optional) Enable Low Power Mode
For many use cases, managing power consumption is critical. Fortunately, the SLN-
VIZNAS-IOT supports low power features out-of-the-box. Low power mode functionality
can be enabled or disabled through the use of the serial commands.
Use the command
“low_power on”
or
“low_power off”
to enable or disable the low
power mode feature supported on the SLN-VIZNAS-IOT.
When low power mode is enabled, the SLN-VIZNAS-IOT will automatically
sleep/hibernate in a state of much lower power consumption than normal, when no
registration/deregistration is taking place and no activity is detected by the camera for
~20s. A
“recognition timeout” message like the one shown in Figure 22 will be displayed
on screen as a warning that the SLN-VIZNAS-IOT will be entering sleep mode within the
next 5 seconds.
SHELL>> low_power on
SHELL>> Low power mode enabled.
