Image segmentation, the process of separating the elements within an image, is frequently used for obtaining information from photomicrographs. However, segmentation methods should be used with reservations: incorrect segmentation can mislead when interpreting regions of interest (ROI), thus decreasing the success rate of additional procedures. Multi-Level Starlet Segmentation (MLSS) and Multi-Level Starlet Optimal Segmentation (MLSOS) were developed to address the photomicrograph segmentation deficiency on general tools. These methods gave rise to Jansen-MIDAS, an open-source software which a scientist can use to obtain a multi-level threshold segmentation of his/hers photomicrographs. This software is presented in two versions: a text-based version, for GNU Octave, and a graphical user interface (GUI) version, for MathWorks MATLAB. It can be used to process several types of images, becoming a reliable alternative to the scientist.