[Insight-users] How to determine minimum between two maximums of a histogram?

[Richard Beare]

Also, check through the list of histogram based threshold filters. At
least one of them works by smoothing the histogram until there are two
maxima.

On Tue, May 29, 2012 at 7:41 AM, Luis Ibanez <luis.ibanez at kitware.com> wrote:
> Hi TomTom,
>
>
> Option A:
>
> Would you consider the option of using the Otsu Threshold Calculator ?
> http://www.itk.org/Doxygen/html/classitk_1_1OtsuThresholdCalculator.html
>
> This will not necessarily give you the minimum between the two classes,
> but, it will give you the point that maximize the variance.
>
>
> Option B:
>
> You can treat your histogram as a 1-D image, and use the filter:
> http://www.itk.org/Doxygen/html/classitk_1_1MinimumMaximumImageFilter.html
>
> that will return the location of the minima and maxima.
>
> To convert from Histogram to Image you can use:
> http://www.itk.org/Doxygen/html/classitk_1_1HistogramToImageFilter.html
>
> and if Smoothing of the histogram is required,
> you can also use any of the ITK smoothing
> filters, in that 1-D image to which you just
> converted your Histogram.
>
>
>        Luis
>
>
> -----------------------------------------------
> On Thu, May 24, 2012 at 9:00 AM, tomtom <ms.rit at web.de> wrote:
>>
>> Hello.
>>
>> Assuming I have a histogram of distances, so basically values between 0
>> and
>> 1.
>> In my case, I always have two "obvious" maximums.
>> Whats the way to get the minimum between those two maximums? (The best
>> would
>> be to smooth the histogram in prior.)
>>
>> Any suggestions?
>>
>> The only thing that comes to my mind is to interpolate a polynomial, and
>> to
>> determine the min, max analytically.
>>
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>
>
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