Motion detection for A/V recording and communication devices
Audio/video (A/V) recording and communication devices according to the present embodiments comprise a processor, a motion sensor, and a camera. In various embodiments, the A/V recording and communication devices are configured to reduce latency and/or to reduce false positive indications of motion.
1. A method for an audio/video (A/V) recording and communication device, including a motion sensor, the method comprising:
gathering, by the motion sensor, information within a field of view of the A/V recording and communication device and generating an output signal;
sampling the output signal from the motion sensor during a first sampling interval;
calculating a first magnitude of the output signal during the first sampling interval;
sampling the output signal from the motion sensor during a second sampling interval;
calculating a second magnitude of the output signal during the second sampling interval;
calculating a difference between the first magnitude and the second magnitude;
comparing the difference between the first magnitude and the second magnitude to a threshold value; and
upon determining that the difference between the first magnitude and the second magnitude is greater than the threshold value, refraining from generating an alert signal.
2. The method of claim 1 , wherein the sampling the output signal during the first sampling interval, the calculating the first magnitude, the sampling the output signal during the second sampling interval, the calculating the second magnitude, the calculating the difference, the comparing the difference, and the refraining are performed by one or more processors of the A/V recording and communication device.
3. The method of claim 1 , wherein the motion sensor comprises at least one passive infrared (PIR) sensor and the gathering the information within the field of view of the A/V recording and communication device comprises receiving infrared radiation from within the field of view of the A/V recording and communication device.
4. The method of claim 1 , wherein the calculating the difference between the first magnitude and the second magnitude determines a rate of change of the output signal from the motion sensor.
5. The method of claim 1 , wherein the threshold value comprises a threshold rate of change.
6. The method of claim 1 , further comprising determining a peak magnitude of the output signal and comparing the peak magnitude to a threshold peak magnitude.
7. An audio/video (A/V) recording and communication device, comprising:
one or more processors;
a motion sensor configured to gather information from within a field of view of the A/V recording and communication device and to generate an output signal based at least in part on the gathered information; and
memory storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising:
sampling the output signal from the motion sensor during a first sampling interval;
calculating a first magnitude of the output signal during the first sampling interval;
sampling the output signal from the motion sensor during a second sampling interval;
calculating a second magnitude of the output signal during the second sampling interval;
calculating a difference between the first magnitude and the second magnitude;
comparing the difference between the first magnitude and the second magnitude to a threshold value; and
suppressing transmission of an alert signal when the difference between the first magnitude and the second magnitude is greater than the threshold value.
8. The A/V recording and communication device of claim 7 , wherein the motion sensor comprises at least one passive infrared (PIR) sensor.
9. The A/V recording and communication device of claim 7 , wherein the calculating the difference between the first magnitude and the second magnitude determines a rate of change of the output signal from the motion sensor.
10. The A/V recording and communication device of claim 7 , wherein the threshold value comprises a threshold rate of change.
11. The A/V recording and communication device of claim 7 , wherein the memory further stores instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising:
determining a peak magnitude of the output signal; and
comparing the peak magnitude to a threshold peak magnitude.
12. An audio/video (A/V) recording and communication device, comprising:
a motion sensor configured to generate an output signal based at least in part on gathering information in a field of view of the A/V recording and communication device; and
one or more processors configure to:
determine a peak magnitude of the output signal;
compare the peak magnitude of the output signal to a threshold value; and
upon determining that the peak magnitude of the output signal is greater than the threshold value, refrain from transmitting an alert signal.
13. The A/V recording and communication device of claim 12 , wherein the motion sensor comprises at least one passive infrared (PIR) sensor.
14. The A/V recording and communication device of claim 12 , wherein the determining the peak magnitude of the output signal comprises sampling the output signal of the motion sensor over multiple sampling intervals.
15. The A/V recording and communication device of claim 12 , wherein the processor is further configured to:
determine a rate of change of the output signal from the motion sensor; and
compare the rate of change to a threshold rate of change.