X-ray topography is a powerful technique for evaluating crystal defects such as dislocations, stacking faults, scratches, and so on. High–performance electronics devices such as microprocessors, solid-state memories, imaging processors are fabricated on dislocation-free Si single crystal wafers. However, device fabrication processes often induce dislocations in the Si wafers that can affect the device’s performance. Because X-ray topography can evaluate these crystal defects efficiently, it plays an important role in the Si industry. Recently, composite semiconductors—for example, SiC-based materials—have been highlighted due to their higher band gap energies and higher breakdown voltages, features superior to those of Si for achieving higher-efficiency power devices. These devices are sought to improve the utilization efficiency of electric energy and reduce carbon dioxide emissions in order to prevent global warming. Although a lot of effort has been devoted to developing growth technology for achieving low-dislocation density crystals, even the highest quality crystals still have many dislocations, in the range of hundreds to thousands per cm². These dislocations can degrade the device’s performance. Therefore, quantitative measurement of the dislocation density is crucial for controlling fabrication yields and improving device reliabilities. Recently, a high-resolution and high-speed X-ray topography measurement instrument called XRTmicron has been released that allows users to acquire high-quality topography digital images. New software that analyzes the obtained digital topography images to count dislocations and identify their types has been developed. In this note, the operation of the software will be introduced.