Hi Cedric, I'm just a user but my interpretation is that mean_intensity is the mean intensity of the pixels in that labeled region, whereas intensity_image is the region within its bounding box. So intensity_image can contain zeros where the label isn't present. See this: from skimage import measure import numpy as np a = np.array([[2,3,4,5],[6,5,4,3]]) b = np.array([[0,1,1,0],[0,1,0,0]]) rp = measure.regionprops(b, a) rp[0].mean_intensity # 4 rp[0].intensity_image # contains a zero, making the mean of this < 4 On Fri, Jul 14, 2017 at 12:23 AM, Cedric Espenel <cedric.espenel@gmail.com> wrote:

Hi scikit-image users/devs,

I'm using skimage.measure.regionprops and I'm little bit confused about a result I get with it.

I'm working with a zstack of a microscopy image that I have segmented/label and I'm trying to get the mean intensity of the labeled region:

region_props = measure.regionprops(label_image, intensity_image)

...

If now I do:

for prop in region_prop:

print('x', prop.mean_intensity)

...

...

print('y', np.mean(prop.intensity_image))

...

prop.mean_intensity and np.mean(prop.intensity_image) give me different value, which confuse me. Can someone help me understand why I'm getting something different?

Thank you in advance for your help.

Sincerely,

Cedric

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