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Colour merge

Colour merge (ImageJ)
Author unknown
File Colour_merge.class
Source not found
Initial release unknown
Latest version unknown
Development status unknown
Category Color processing


This plugin allows you to merge two grayscale stacks into a single RGB stack. It is useful e.g. to merge a brightfield with the corresponding fluorescence image, or two different dye images of the same series.


Adapted from the MBF ImageJ manual:

The Plugins  › Color functions  › Color Merge function gives the user the option of using the Difference arithmetic processing on the image stacks you select. This is not strictly a merge (when cyan and magenta merge they produce white, not yellow) but facilitates visualization of the separate channels (See Demandolx, D. & Davoust, J. (1997), "Multicolour analysis and local image correlation in confocal microscopy", Journal of microscopy 185: 21-36. You can perform a true merge if you turn off the “Difference” option.

Run the plugin and select the two images or stacks to be merged. It can be 8-bit, 16-bit, RGB... Select the desired colors from the drop-down options. <Current> uses the LUT that the image currently has (this is often the desired LUT). The “Difference” option performs a “difference” arithmetic operation rather than a “addition”. If the “Pre-sub 2 from 1” option is checked the second image is subtracted from the first prior to merging.