Rectangular border on non-rectangular point cloud

[cmuns]

Hello,

I'm a relatively new user, and I've been using the Rasterize tool to convert a .las point cloud to a DEM format usable in QGIS.

However, my .las point cloud appears with a rectangular border in CloudCompare (CC). When I rasterize my point cloud, the border area is also filled with zero values, since I'm interpolating values for blank areas.

cloud with rectangular border.JPG (34.06 KiB) Viewed 589 times

The areas between the yellow rectangular border and the edges of my point cloud are filled in.

When I export the rasterized geotiff, the border area remains tacked on. This adds an unnecessary rectangular border onto the DEM once I load it into QGIS.

Is there a way to limit interpolation and accompanying filling in of blank areas to the extent of my original point cloud?

Thanks in advance.

[daniel]

The (yellow) rectangular border you see is the "axis aligned" bounding box. So it's aligned on the default X and Y axes.

When you use the 'Rasterize' tool, that's the same. By default it generates an axis aligned raster 'grid'. But you can avoid filling the empty cells (see the 'fill empty cells' field that you can leave to 'empty').

Otherwise, you can rotate your cloud so that it is axis aligned (with the 'Edit > Transform' tool, or manually with the 'Edit > Rotate/Translate tool - you can even lock the rotation about 'Z'). Then use the Rasterize tool. And eventually apply the inverse transformation to your raster (once again with the 'Edit > Apply transformation' tool' and checking the 'inverse' option - or by copying the transformation manually applied that appears in the Console and then applying its inverse with the 'Edit > Apply transformation' tool).