Reposted from smathermather. Thanks to the tireless work of the folks behind the Zanzibar Mapping Initiative , I have been exploring the latest settings in OpenDroneMap for processing data over Stone Town. I managed to get some nice looking orthos from the dataset:.
But, excitingly, I was able to extract some nice looking surface models from the dataset too. This post is a small homage to the late his Majesty Sultan Qaboos. Given the strong affinity and shared history between Zanzibar and Oman, it seems fitting to post these.
In a previous blog post, we explored how we can quite effectively derive terrain models using drones over deciduous, winter scenes. We ran into some limitations in the quality of the terrain model: the challenge was removing the unwanted features things like tree trunks while retaining wanted features large rock features.
For our use case, however, we can use the best parameters for this area, take a high touch approach, and create a really nice map of a special area in our parks for very low cost. In the end, the trick was to extract as good of a depthmap as possible depthmap-resolution: in my case, set the point cloud filtering Simple Morphological Filter or SMRF smrf-window and smrf-threshold to 3 meters to only filter things like tree trunks, and set ignore-gsd: true to ensure we are keeping the highest quality data all the way through the toolchain.
This is a much less noisy result. Unfortunately, I ran it at the wrong resolution, so I am rerunning at full resolution now and hope to see something similar. If we want to understand terrain, we have a pricey solution and an inexpensive solution.
