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mmhistogram
Find the histogram of the image f.

Synopsis

function h = mmhistogram ( f , option )

Input

f Image Gray-scale (uint8 or uint16) or binary image
option String

Default: 'uint16'

Values: "uint16" or "int32".

Output

h Image Gray-scale (uint8 or uint16) image

Histogram in a uint16 or an int32 vector.

Description

Finds the histogram of the image f and returns the result in the column vector h. For binary image the vector size is 2, for gray-scale uint8 and uint16 images, the vector size is the maximum pixel value plus one. h(1) gives the number of pixels with value 0.

Examples

f=uint8([0 1 1 2 2 2 5 3 5]);

h=mmhistogram(f);

h'

ans =
      1      2      3      1      0      2

f=mmreadgray('lenina.tif');

mmshow(f);

h=mmhistogram(f);

plot(h);
f h

Equation

Algorithm

function h = mmhistogram_equ(f)
  m=max(f(:));
  h=zeros(m+1,1);
  for i=1:m+1
    h(i)=length(find(f==(i-1)));
  end

See also

mmstats Find global image statistics.
mmblob Blob measurements from a labeled image.
mmgrain Gray-scale statistics for each labeled region.
mmfreedom Control automatic data type conversion.
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