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iahistogram
Image histogram.

Synopsis

h = iahistogram( f )

Implemented in Python.

Input

f Image. Gray-scale (uint8 or uint16) or binary image (logical).

Output

h Image. Gray-scale (uint8 or uint16) or binary image (logical).

Examples

>>> f = iaread('woodlog.pgm')

              
>>> iashow(f)

              
(256, 256) Min= 0 Max= 255 Mean=91.026 Std=53.61

              
>>> h = iahistogram(f)

              

              
>>> g,d = iaplot(h)

              
>>> g('set data style boxes')

              

              
>>> g.plot(d)

              
>>> 

            

            

              
                

                  
                  
                  
                

                

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Source Code

      

        
def iahistogram(f):
    from Numeric import asarray, searchsorted, sort, ravel, concatenate, product
    f = asarray(f)
    n = searchsorted(sort(ravel(f)), range(max(ravel(f))+1))
    n = concatenate([n, [product(f.shape)]])
    h = n[1:]-n[:-1]
    return h
    

      

    

    

      

        

          
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