to calculate histogram features

to calculate histogram features using the equation in the following link,.....

http://img59.imageshack.us/img59/204/histogram.png

will it work if i use imhist function..... but how to implement the summation with the values i....... please do reply....

Answer 1

[Walter Roberson]

Yes, you could use imhist(), but remember you need to break the image up into MxM blocks, and imhist() is a more expensive calculation than hist() or histc() is.

[Elysi Cochin]

to get the result in the equation which function shud i use.... imhist or hist or histc...

[Walter Roberson]

It doesn't matter. You should be thinking more about what bin centers or edges you are going to pass in to the histogram routine you choose.

[Elysi Cochin]

sir if i use this line of code..... which parameters maximum i need to obtain for the reault in the equation.... please do reply...

 [pixelCount grayLevels] = imhist(grayImage)

is it

 max(pixel count)

or

 max(grayLevels);

[Walter Roberson]

"where histo(i) is the value of the histogram with the intensity i"

so you need to be concerned with the output that reflects histogram values, not histogram intensities.

I think that "H = arg i max(histo(i))" is intended to mean that H is the "i" such that histo(i) is the maximum -- that is, the index of the maximum intensity.

And you still need to think more about what bin centers or edges you are going to pass in to the histogram routine you choose.

[Elysi Cochin]

sir please could you show me how to write the code for what u explained above for a image as a whole..... please reply sir....