Altering Input Bands for Brightness Feature Calculation
By default, the calculation of the Brightness feature (Feature View > Object Features > Layer values > Mean > Brightness) is the sum of all input layers divided by the number of input layers per object. In the example below, we have 4 input layers (Layer 1, Layer 2, Layer 3 & Layer 4), therefore the brightness for each object will be ((Layer 1 + Layer 2 + Layer 3 + Layer 4) / 4).
If you only want to have Layer 1 and Layer 3 included in the calculation of the Brightness feature, you can easily do so via the Classification menu (Classification > Advanced Settings > Select Image Layers for Brightness...). In the Define Brightness dialog, simply select the layers you want to include in the Brightness feature calculation (highlighted in blue) and click "OK". In the image below you see different examples or the Brightness feature calculation based on difference selections, on the left Layer 1 & Layer 2 are selected for the calculation of the Brightness feature, in the center Layer 3 & Layer 4 are selected and on the right all input Layers are selected. Enjoy showing off with this little trick to your colleagues.
Was this article helpful?