Selected pixel count

[Ofnuts]

Open the python console and enter this:

Code:

image=image=[x for x in gimp.image_list() if image.ID==5][0]

Where you replace "5" by the image ID, which is the number you find in the title bar:

   

Then to get your pixel count:

Code:

pdb.gimp_drawable_histogram(image.active_layer,0,0.,1.)[3]

If you want to redo this for another selection, just repeat that last line after changing the selection, since the image will be the same.

To be a bot more complete, in the histogram call, the args are:

• The layer/drawable for which you want statistics
  
• A channel identifier (Value (maxOf(R,G,B), Red, Green, Blue, Alpha, Luminance)
  
• The minimum value you want inlcuded
  
• The maximum value you want inlcuded (so you define a range between these two), like with the handles in the
  
•  histogram display
  

The result is a list if numbers:

• Average value
  
• Standard deviation
  
• Median value
  
• Pixel count for the whole selection (range not taken in account)
  
• Pixels count for the pixels within range
  
• Ratio of the two previous values
  

So the code I gave you extracts the 4th value (index=3, since this is 0-based). The output of the API is in the [0..255] range instead of the [0. .. 1.0] range so you add a division by 255 if necessary.

It is of course also easy to format this output differently, and writing a script to write the values to file wouldn't be difficult.

Here is how the API and the GUI relate: