Sometimes it makes sense to change the range of pixel intensity values of an image layer, for instance:

• to normalize layer values (i.e. 8bit; [min … max] -> [0 … 255])
• to stretch an NDVI layer as input for the ‘multiresolution segmentation’ algorithm (works best with 8-bit input layer range)
• to shrink layer values (i.e. from [0 … 32767] -> [0 … 1]) for CNN algorithms
• to clip histogram to remove (no) data values
• and much more and any combination

eCognition users can do this with the ‘layer arithmetics’ algorithm. To make life easier, Christian Weise created in 2012 a customized algorithm ‘modify layer histogram’ for linear histogram modifications.

To use the ‘modify layer histogram’ please download the customized algorithm and load it into your project, after it you will find the ‘modify layer histogram’ in the algorithm list. The ‘Example Project - Modify Layer Histogram' provides use case examples.

Important algorithms used in this project:

• show html help
• update array
• layer arithmetics

Download ‘Modify Layer Histogram’ algorithm

Download 'Example Project - Modify Layer Histogram'