[GRASS-dev] r.in.lidar tuning

[Markus Neteler]

On Tue, Oct 8, 2013 at 4:31 PM, Markus Metz
<markus.metz.giswork at gmail.com> wrote:
> Markus Neteler wrote:
>>
>> One more wish comes to mind (indeed, I started cross-porting but :-)
>>
>> v.in.lidar comes with a filter (which should perhaps be generalized to
>> the nth return; or, the last *is* the nth return but then "mid" could
>> be more than one in this case?):
>
> Yes, for n returns, the first return is number 1, the last return is
> the nth return and mid returns are all returns in between, i.e. none
> for 2 returns. Choosing the nth return does not make sense to me.

ok

>>     filter   Only import points of selected return type
>>               If not specified, all points are imported
>>              options: first,last,mid
>>
>> which would be great for r.in.lidar as well to avoid that I need to
>> split the file with las2las beforehand.
>
> Why would you want to do filtering? The r.in.lidar methods min, max,
> mean, median, percentile are not sufficient?


I omitted to mention the sometimes existing classification of returns
and had in mind to be able to restrict the import to e.g. ground
points only, or the like. Then apply the methods min, max, etc only to
the selected subset of LiDAR points.

markusN