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Analyzing the particles
Home Documentation SmileLab Scripting Extensions Particles Analyzing the particles  
AnalyzeParticles(m, gray_level, min_area)
Returns information about the particles found in the image provided as a matrix m. The particles are detected by thresholding at the gray level gray_level. Particles with an area smaller than min_area are not considered.
m: a matrix
gray_level: the threshold gray level, an integer in [0 ... 255]
min_area: the minimum area in pixels, a real number
The information returned by AnalyzeParticles is a list of records, one per particle. Each record contains the following key-value pairs:
centre
the position of the center of the particle, as a list of two real numbers
area
the area of the particle in pixels
perimeter
the perimeter of the particle in pixels
major axis and minor axis
the lengths of the major and minor axes of the particle in pixels
angle
the angle of the major axis of the particle with respect to the horizontal, in radian
ListParticles(m, gray_level, min_area, column_sorted)
Same as AnalyzeParticles, but returns the results as a string (rather than an AppleScript list). The string is a tabulated array with 6 columns: x, y (position of the center of the particle), area, minor and major axes and perimeter. The table is sorted according to the column index specified by column_sorted.
column_sorted: the index of the sorting column, an integer in [1 ... 6]
ShowParticles(m, gray_level, planar_view_ref)
Like AnalyzeParticles, but no information is returned about the particles: ShowParticles displays the particles in a new graphic window, as red contour lines over the grayscale image. ShowParticles returns a reference to the new planar view.
planar_view_ref: you can pass the reference returned by ShowParticles, in order to have ShowParticles refresh the graphic rather than create a new one
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