gives a binary image in which white pixels correspond to the zeros and zero crossings in image.

ContourDetect[image, delta]
treats values in image that are smaller in absolute value than delta as zero.

Details and OptionsDetails and Options

  • ContourDetect finds pixels with zero value as well as pixels with positive values that have at least one negative neighbor.
  • For color images, ContourDetect operates on the intensity averaged over all channels.
  • ContourDetect works with images of arbitrary type.
  • ContourDetect[m] finds zeros and zero crossings in a numerical matrix m, returning a sparse array.
  • ContourDetect[m, delta] effectively chops values smaller in magnitude than delta.
  • ContourDetect by default treats all eight pixels surrounding a given pixel as adjacent.
  • The option setting CornerNeighbors->False treats only the four pixels in the coordinate directions as adjacent.
  • Using the option setting CornerNeighbors->None, ContourDetect operates on the dual grid whose pixels correspond to the corners in the original image, thereby reducing the dimensions of the resulting image by one pixel.
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