Short follow up: Photogrammetrically Derived Point Clouds

In my previous post, https://smathermather.wordpress.com/2014/02/04/big-dmn-post-photogrammetrically-derived-point-clouds/, I briefly cover software for creating photogrammetrically derived point clouds.  I didn’t summarize, like this, but PDPCs can be created in three easy steps: Structure from Motion for unordered image collections Clustering Views for Multi-view Stereo Multi-view stereo (dense point cloud reconstruction) But, unfairly, I gloss over some of the complications of creating meaningful data from PDPC processing. Truth told, … Continue reading Short follow up: Photogrammetrically Derived Point Clouds

Big d@mn post: Photogrammetrically Derived Point Clouds

I chatted with Howard Butler (@howardbutler) today about a project he’s working on with Uday Verma (@udayverma @udaykverma) called Greyhound (https://github.com/hobu/greyhound) a pointcloud querying and streaming framework over websockets for the web and your native apps. It’s a really promising project, and I hope to kick the tires of it really soon. The conversation inspired this post, which I’ve been meaning to do for a … Continue reading Big d@mn post: Photogrammetrically Derived Point Clouds

2.5D TINs in PostGIS

(edited: changed TIN to TIN Z) (edited again — function already exists as a flag in ST_DelaunayTriangles… .) Uh, I wrote a function for nothin’… As Regina points out in the commments, this functionality was rolled into 2.1 with a flag. Her example: For the record, my code is about 2% slower on a dataset that takes ~50minutes to triangulate . —————————————— Original Post —————————————— … Continue reading 2.5D TINs in PostGIS

UAS (drone) Footprint Geometries Calculated in PostGIS with SFCGAL — for real this time

In my earlier post, I made a claim that SFCGAL was used in this figure: It dawned on my afterwards, while I was using 3D, I hadn’t actually employed any of the analysis goodies that come with SFCGAL.  Well, here it is– a footprint as calculated using the view angles and a real terrain model: Here it is compared with the initial calculation: Continue reading UAS (drone) Footprint Geometries Calculated in PostGIS with SFCGAL — for real this time

Photogrammetry using Bundler, PMVS, GDAL, and PostGIS.

Photogrammetric like ortho-photos rendered with GDAL/PostGIS from 3D point clouds created in Bundler and PMVS?  Yes indeedeedoo: Point cloud in meshlab:   And “orthophoto” derived from voronoi polygons in PostGIS, rendered to tif with gdal:     Hat tip to my3dscanner for making it so easy to generate the point cloud.  More on this later. Continue reading Photogrammetry using Bundler, PMVS, GDAL, and PostGIS.