These are tools for working with GIS data, in particular, LiDAR and raster data and geodetic transformation. They're mostly experimental and not presented for production use, though they have been very useful in my work.
This program is experimental. Please do not use it for important work.
This is a c++ program that transforms a point cloud in LAS format from any ITRF reference frame/epoch to NAD83(CSRS) at any epoch. The algorithm is based on Craymer, M. R. (2006). The evolution of NAD83 in Canada, 60(2), 151–165. Read more about NAD83(CSRS) here.
This is a simple program that grids one or more LAS files into a GeoTiff. The user can select the classes, and a number of methods, such as mean, min, max, stddev, density and quantiles. The quantile selection produces a single band with quantile i of n, with the 0th and nth bands being the min and max, respectively.
This program computes zonal statistics from a point cloud in LAS format from either a collection of polygons in Shapefile format, or from a classification raster. If a Shapefile is used, each polygon is updated with columns for the statistics. If a raster is used (it must be the Byte type), statistics are computed for each unique cell value and output as a CSV file.
The user may select which point classes are considered, but this behaviour is different depending on whether raster of vector is used. For rasters, statistics are computed for each cell value and for each point class. So, if there are two cell values and three point classes, there are six records in the table. For vectors, statistics are grouped for all given classes.
This program enables the user to develop something like this, where the x-axis is cell IDs, and the y-axis is canopy height.
Click on the image to view an interactive map.
This program mosaics overlapping rasters, using the first as a "background" which sets the spatial extent of the result. Successive rasters are blended into the result using a sigmoid (tangent) curve over a given distance.
The image below shows the sigmoid blend on an artificial 10m step.
This program converts NRCAN's NAD83(CSRS) velocity grid to a GeoTiff format. The grid contains horizontal and vertical velocities for calculating tectonic and isostatic change of coordinates over time.
