raster - Converting LiDAR data (.laz) to DSM in .asc format

I'm looking to convert a LIDAR scan in .laz format into a DSM in ASCII Grid format, in order to calculate RF propagation in an urban environment from a given transmission location (bonus: converting the georeferencing from NAD83 to WGS84).

My source data is a set of scans from NOAA, and I'm working to ingest them into another application which wants it in .asc format, like so:

ncols        2454
nrows        1467

xllcorner    -1.475333294357
yllcorner    53.378635095801
cellsize     0.000006170864
NODATA_value      0
0 0 0 0 0 0 0 0 0 0 0 0 0 ...

Being able to batch-process the data would definitely desirable.

Answer

As mentioned by Aaron, the CanopyModel tool from Fusion can build Digital Surface Models (DSM).

In order to directly use the compressed LiDAR files .laz as input of CanopyModel, it is necessary to have the file LASzip.dll from LASzip program installed within Fusion's install folder.*

By default the CanopyModel will assign the elevation of the highest return within each grid cell to the grid cell center. Some alternative settings for the tool are available through the switches, such as smoothing filters. For example, see: How to de-noise a DSM.

In your case, it is wanted to export the DSMs as .asc files, so use the switch ascii (the default exports it as .dtm). According to Fusion's manual:

ascii. Write the output surface in ASCII raster format in addition to writing the surface in DTM format.

Then, the CanopyModel syntax would look like the following:

\CanopyModel /ascii \surfacefile cellsize xyunits zunits coordsys zone horizdatum vertdatum \datafile1

The CanopyModel tool can be easily used in batch-processing as it is a stand alone program (.exe). Moreover, the datafile argument (which is the input file, i.e. the raw .laz file) supports wildcard or name of text file listing the data files.

_{*If one wants to use one program at a time, first decompress the .laz files (see: Converting LiDAR files from LAZ to LAS format), and then, run CanopyModel using .las format.}