Perceptually Uniform Projection (PUP)

PUP is an ImageJ/Fiji macro that uses the CIELAB color space to generate a perceptually accurate display of two grayscale images as a single color image. More information about PUP and its derivation can be found in the following publication:

Taylor, A. B., Ioannou, M. S., Watanabe, T., Hahn, K., & Chew, T. L. (2017). Perceptually accurate display of two greyscale images as a single colour image. Journal of microscopy, 268(1), 73-83. https://doi.org/10.1111/jmi.12588

File Descriptions

Our code consists of three files:

• PUP_CODE.ijm - the ImageJ/Fiji macro
• PUP_NR.lut - the narrow range lookup table
• PUP_BR.lut - the broad range lookup table

Dependencies

PUP code depends on ijp-color written by Jarek Sacha. The Color and Multiband Processing plugin (which is part of IJ-Plugins Toolkit) can be installed through the ImageJ/Fiji update site https://sites.imagej.net/IJ-Plugins/. Instructions can be found at https://github.com/ij-plugins/ijp-toolkit/wiki.

Installation

1. Install IJ-Plugins Toolkit dependency.
2. Place the lookup table files (i.e., PUP_NR.lut and PUP_BR.lut) in the default ImageJ luts folder (typically, ImageJ.app/luts or Fiji.app/luts).
3. Open/Run PUP_CODE.ijm through the ImageJ/Fiji menu system (Plugins > Macros > Run…). Alternatively, drag-and-drop the file onto the ImageJ/Fiji toolbar.