I recently used the answer from Using Orfeo Toolbox object based classification in QGIS tutorial/workflow? to perform an object base segmentation on a SPOT image I acquired a while ago. I tried both of the solutions given, they both work mostly but I have an issue with the second half of the first one.
What it says, in short, is that after using the "Exact large scale meanshift segmentation" tool from the Orfeo Toolbox via Qgis, you need to create and edit training areas manually using a shapefile. The thing being that the said shape is needed afterwards as a signature XML file containing mean values and variance for each of the training areas. I did think about using the semi automatic classification tool, creating the ROIs and converting them into an XML signature file directly. The issue being here that any manual edit on the ROI shapefile makes QGIS insta-crash 8 times out of 10, and when I'm actually able to do it, it crashes again when I try to export the shapefile as a spectral signature via the inbuilt conversion tool.
Is there any work-around that might help creating the XML file from a shapefile? Is semi automatic classification the best way to create it? If not, what should I use?