Feature Calculator

Hi all,

I got two issues concerning the Feature Calculator (Beta).

1. Is there any explanation (not simply mathematically) available for all the features?

2. How is it possible to extract Tamura features from segments?

When selecting the segment in Labeling at the coniguration window, all of the features work, except Tamura. It's possible to calculate the Tamura features of the whole image, but that's not what I'm aiming for.

 

Best

Assindia

Hi Assindia,

1. The Feature Calculator node can give you a description for each feature if you click on it's description button (see attached screenshot).

2. To calculate the Tamura features for segments, you can use the Image Segment Features node, which also provides these features, thank you for reporting this bug, we will investigate it.

Best,

Gabriel

 

Hi Gab,

Thanks for replying!

1. Already noticed this before. Works well for Tamura. Unfortunately different feature sets like Haralick's have no complete description. The hyperlinks aren't working there and in literature I primarily found mathematic expressions...

2. Thanks for this obvious solution!

 

Best,

Assindia

Hello,

  1. I agree the hyperlinks are not clickable strangely, although the mouse turn to a hand-icon.

  2. I have used the node to compute some shape descriptors (Geometric features 2D, Image moments and Zernike). As far as I know those features only use the information from the Labeling and not from the image/Pixel values. Still I had filled in the Image field with my image column in case I would be adding some image-based features in the future.
    The execution of the node is actually much slower in this case compared to when I chose None for the Image field (since I am indeed not using the information from the image).
    So I was wondering if the node could somehow guess from the choice of features if it actually needs to analyze the Image column.

Thanks
Laurent

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If you select an Image column, the node tries to apply the selected features to the image, masked by the Labeling. This makes the calculation slower, sometimes unnecessarily.

Because such a feature is difficult to get right and especially not easy to communicate to our users, we decided that we will return to different nodes per feature calculation scenario (Image Features, Segment Features, Image Segment Features) in the future.

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