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This component calculates and outputs the following statistical values of a grayscale image:

  • Number of non-zero pixels
  • Sum of all pixels
  • Mean and standard deviation of all pixels
  • Minimum and maximum value among all pixels

Combined with (adaptive) background subtraction, such values are useful to detect sudden changes or out-of-the-ordinary frames in a video stream.


SwisTrack GrayImage.jpg

A grayscale image.


The statistical values are written to the NMEA stream.


Each of the values mentioned above can be enabled or disabled. For performance reasons, it is advisable to enable only those values which are needed.