Interface BackgroundAlgorithmGaussian

All Known Implementing Classes:
BackgroundMovingGaussian, BackgroundMovingGaussian_IL, BackgroundMovingGaussian_IL_MT, BackgroundMovingGaussian_PL, BackgroundMovingGaussian_PL_MT, BackgroundMovingGaussian_SB, BackgroundMovingGaussian_SB_MT, BackgroundStationaryGaussian, BackgroundStationaryGaussian_IL, BackgroundStationaryGaussian_IL_MT, BackgroundStationaryGaussian_PL, BackgroundStationaryGaussian_PL_MT, BackgroundStationaryGaussian_SB, BackgroundStationaryGaussian_SB_MT

public interface BackgroundAlgorithmGaussian

Background model in which each pixel is modeled as an independent Guassian distribution. For computational efficiency each band is modeled as having a diagonal covariance matrix with off diagonal terms set to zero, i.e. each band is independent. See [1] for a summary. This is an approximation but according to several papers it doesn't hurt performance much but simplifies computations significantly.

Internally background model is represented by two images; mean and variance, which are stored in GrayF32 images. This allows for the mean and variance of each pixel to be interpolated, reducing artifacts along the border of objects.

Tuning Parameters:

  • learnRate: Specifies how fast it will adapt. 0 to 1, inclusive. 0 = static 1.0 = instant. Try 0.05
  • threshold: Pixel's with a Mahalanobis distance ≤ threshold are assumed to be background. Consult a Chi-Squared table for theoretical values. 1-band try 10. 3-bands try 20.
  • initial variance The initial variance assigned to pixels when they are first observed. By default this is Float.MIN_VALUE.

[1] Benezeth, Y., Jodoin, P. M., Emile, B., Laurent, H., & Rosenberger, C. (2010). Comparative study of background subtraction algorithms. Journal of Electronic Imaging, 19(3), 033003-033003.

  • Method Details

    • getInitialVariance

      float getInitialVariance()
      Returns the initial variance assigned to a pixel
      Returns:
      initial variance
    • setInitialVariance

      void setInitialVariance​(float initialVariance)
      Sets the initial variance assigned to a pixel
      Parameters:
      initialVariance - initial variance
    • getLearnRate

      float getLearnRate()
      Returns the learning rate.
      Returns:
      0 (slow) to 1 (fast)
    • setLearnRate

      void setLearnRate​(float learnRate)
      Specifies the learning rate
      Parameters:
      learnRate - 0 (slow) to 1 (fast)
    • getThreshold

      float getThreshold()
    • setThreshold

      void setThreshold​(float threshold)
    • getMinimumDifference

      float getMinimumDifference()
    • setMinimumDifference

      void setMinimumDifference​(float minimumDifference)