Agisoft Metashape

Agisoft Metashape => General => Topic started by: JulienGroenenboom on September 11, 2014, 04:01:18 PM

Title: Filtering water, vegetation etc.
Post by: JulienGroenenboom on September 11, 2014, 04:01:18 PM
Hello,

I am dealing with a 3D model of a beach. I would like to filter everything except the sand before making a DEM. I want to remove water, vegetation, sailboats, beach clubs etc.

Does anyone have a recommendation for good filter software?
Anyone experience with CANUPO plugin from CloudCompare? [ Link: http://www.geosciences.univ-rennes1.fr/spip.php?article1284&lang=fr ]

Any suggestions are very welcome.
Title: Re: Filtering water, vegetation etc.
Post by: photogrammetrix on September 11, 2014, 04:30:15 PM
Hi Julien,

I have not tested CANUPO in deep. As fa as I digged into it,  It works well with CC but tends to take looong time when dealing with larger point clouds.

Is there a chance of preclassifiying the images and using e.g. a non-shore mask?? You may take a look at the WEKA trainable sgmentation classifier in FIJI / ImageJ or the SIOX Segmentation tool in GIMP or FIJI. Batch processing should be possible via scripting .

Another idea is to exploit rgb and normal values of the point-cloud and create a kind of conditional filter with help of the python Api.

Cheers

Title: Re: Filtering water, vegetation etc.
Post by: stihl on September 12, 2014, 10:53:14 AM
Hi,

Photoscan has a ground filter feature. You should play around with the parameters, it should give you what you want i.e. a DTM (not DEM) with the vegitation etc filtered out. As for the water, if it's the shoreline the easiest way to remove that is simply by manually deleting the water points from the dense cloud.