count number of pixels having certain value

[Girish Kumar]

Dear all,

          How to get the number of pixels having specific value in an image. I have made a binary image from NDVI by thresholding it. Now want to calculate the area. It can be done if I get the number of pixels having value 1.Kindly give your suggestion.

With Warm Regards

Girish

[Pete Bunting [pfb]]

Hi Girish,

The histogram of the image is the easiest way. For the example you give I would use rsgislib.rastergis.populateStats and then read the histogram from the RAT. However, you can also use rsgislib.imagecalc.getHistogram which returns a list.

Best wishes,

Pete

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[Girish Kumar]

Hi Pete,

   Thank You for your quick response. I will try it.

With Warm Regards

T P Girish Kumar

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