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Mathematica > Data Manipulation > Image Processing & Analysis > Color Processing > ImageLevels >
Mathematica > Visualization and Graphics > Graphics Options & Styling > Colors > Color Processing > ImageLevels >
Mathematica > Visualization and Graphics > Symbolic Graphics Language > Graphics Directives > Colors > Color Processing > ImageLevels >
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ImageLevels

ImageLevels[image]
gives a list of pixel values and counts for each channel in image.
ImageLevels
bins pixel values into n equally spaced levels.
ImageLevels
puts all values into n bins between min and max.
MORE INFORMATION
  • ImageLevels gives a list of results for each channel. The result for each channel is a list of pairs, each giving the minimum value and count for a particular pixel value bin.
  • For binary images, ImageLevels[image] gives a result of the form .
  • ImageLevels by default takes the first bin to start at and the last one to end at . Channel values below or above are placed in the first and last bins, respectively.
  • ImageLevels takes the first bin to start at min, and the last bin to end at max.
  • ImageLevels[image, n, All] gives n equally spaced bins, extending over the complete range of values in each channel.
  • ImageLevels gives the levels of image scaled to the range 0 to 255.
  • ImageLevels[image, All] returns a tally of all pixel values occurring in image.
  • ImageLevels puts pixels with values below the first bin into the first bin, and pixels with values above the last bin into the last bin. With an option setting False, pixels with values outside the range of bins are not counted.
EXAMPLESCLOSE ALL
Basic Examples   (2)
Count the number of pixels in each of 10 intensity levels:
Levels of a three-channel image:
Count the number of pixels in each of 10 intensity levels:
In[1]:=
Click for copyable input
Out[1]=
 
Levels of a three-channel image:
In[1]:=
Click for copyable input
Out[1]=
Scope   (5)
Levels of a binary image:
Levels of an image in the range 0 to 255:
Levels for a random image that has intensity values outside the normal range from 0 to 1:
Explicit data range setting:
Tally of all levels in a random image:
Options   (1)
By default, pixel values outside the normal range are clipped:
Do not clip values outside the normal range:
Applications   (1)
Plot levels of a random image with a Laplacian distribution of pixel values:
Possible Issues   (1)
A tally of all levels in an image returns a result with non-uniform distribution of bins:
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