ImageJ

OtoRing - An ImageJ plugin to aid otolith ring identification.
The source code is available at https://github.com/tektonia/otoring
To use the ImageJ Updater use the following url: http://sites.imagej.net/OtoRing/

Example:

Blue Whiting (Micromesistius poutassou) otolith

1 - Select a Region Of Interest using the Line tool

Opaque and Translucent rings

2 - Execute the OtoRing plugin

Graph plots intensity by distance

3 - The result is shown

OtoRing Parameters

4 - Use the OtoRing Parameters to improve the results

Developed by Patrícia Gonçalves (IPMA/Portugal) and Vitor Vaz da Silva (ISEL/Portugal)