FILTER PACKAGE USER S GUIDE

Transcription

1 FILTER PACKAGE USER S GUIDE 1

2 CONTENT I. Introduction... 3 II. Installation... 3 III. Using the filters... 4 a- General... 4 b- Edge filter... 5 c- Uniform filter... 7 d- Angular filter... 8 e- Circle pipe filter... 9 f- Remove scan points along x,y,z g- Remove scan points behind planes IV. Known issues V. Updates

3 I. Introduction The filter package is designed to provide lighter and cleaner data. Our filters are directly applied on the fls files. We recommend that you keep your original project and that you work on a exported project to do the final cleaning / filtering. Edge filter : removes most mixed points that are behind the edges / pipes. Uniform filter : keeps a minimum distance between 2 points. Angular filter : keeps the points in a vertical range (low high angle) Circle / Pipe filter : this is more a kind of new selector rather than a filter. This feature allows the user deleting all the points that are inside / outside a circle or a pipe. This is particularly useful for tanks. The user can clean the tank to keep the cylindrical shell. Plane filter: removes what s behind planes. Useful to clean the points that are behind the openings (windows, doors ). II. Installation Open Faro Scene or Scene LT and go into tools Apps, and install the fpp file. Licensing : You have to be online to activate the plugin. Click on one icon of the filter (green icons) to open the trial \ buy \ activation interface. 3

4 The plugin can be tested for 3 days. After this period, you can buy it on the Faro Appstore. Clicking on buy will open the Faro website : Go to the TagLabs filter plugin package and click on buy. After buying the plugin, you ll get a code in your mailbox (we call it «TAN code»). Please copy-paste this code to activate the plugin (please use right mouse click\paste to paste the TAN code, as CTRL+V doesn t work in this window). You must be online to do the activation as your computer will be connected to a license server. Once the activation is ok, you can use the plugin. In case you are using several versions of Scene on your computer (5.3, 5.4, 5.5, + LT versions ), you can install the plugin on all of them without buying a new license. III. Using the filters a- General The filters are represented by green icons : A = angular, U = uniform, E = edge, C = circular, P = plane The filters cans be applied on a single scan, a selection of scans (mouse + ctrl or shift in the structure tree), or a cluster. 4

5 First of all, when the plugin is started, you ll be asked to choose the unit (meters or feet). Indeed, the internal unit in Scene is always the meter, even if you set the feet in the options table. Once the unit is set, it will be used for this plugin during the whole work session. To change it, you ll have to close / open Scene, or to deactivate / activate the plugin. Important : Before starting a filter, please make sure that you selected the scan(s) in the structure tree. At the end of a filter, the scans in the structure tree will have a small blue star that shows that some points were removed. Save the project to keep the modifications. In case the result isn t satisfying, unload the scans without saving them, and try again with another value. The plugin doesn t lock Scene : you can still work on other scans (open, view, measure ) while filtering. Due to an API limitation, we can t automatically save and unload the scans that have already been filtered to free the RAM, like the inbuilt preprocess function of Scene does. So, in case you want to apply the filter on a large number of scans, make sure you have enough free memory. The plugin will also use some extra memory for the scan that is under calculation. b- Edge filter New: this filter is now much faster (speed x8). It also supports multithreading. Just make sure you have enough free memory when starting a multithreading calculation: the plugin will load and clean all the selected scans at once. 3 levels are available: low, medium, high. The high level is the most aggressive one. 5

6 The filter has to be applied on a whole scan as it is currently not possible to apply it on a area (API limitation). Before After *please see chapter IV : check the angular range in the new scan properties. Tips : Here are the levels that we use at TagLabs : - low level filter for interior scans in classical buildings - low / medium level filter when scanning building facades - medium / high level filter in dense industrial environments, or for ornaments that are far away from the scanner 6

7 In case you did a scanning position that is very closed to a wall, the filter might remove the points that were captured with a very low laser beam angle. To avoid that, first try the low level filter. We generally avoid such situations by doing enough scanning positions to ensure a good overlapping. Limitations : Some mixed points that are far away from the scanner might not be removed, especially when the edge is closed to the surface that is right behind. This is because the distance between the stray points is the same as the standard distance between the good points. All in all, the plugin should be able to remove more than 99% of the mixed points and deliver much cleaner data. In case you want to apply the uniform filter too, please apply the Edge filter first. c- Uniform filter This filter will keep a minimum distance between 2 consecutive points in a scan. It will not change the distance between the points that already have a spacing that is bigger. 7

8 before after Tip for Webshare creation: Applying the uniform filter has an advantage : the f3s files used to create the webshare become much lighter. You can divide the weight of a webshare project by more than 2, depending on the type of project (interior or exterior). Moreover, you won t deteriorate the visual quality on the panorama pictures. Keep a reasonable spacing (< 1cm), otherwise the measuring in the webshare interface might be more difficult. Apply the filter before creating the scanpointclouds. We usually set 5mm when filtering the scans for Webshare purposes. d- Angular filter Set a range (low and high angle). All the points that are outside this range will be removed. 8

9 e- Circle pipe filter Select a circle* or a pipe in the structure tree, add it in the dialog box, give an offset (the cleaning starts at xx cm from the circle), and choose to remove the points that are inside or / and outside the circle / pipe. *requires the object manager package Outside only : the filter will remove all the points that are outside an infinite cylinder that contains the circle + the offset. 9

10 Inside only: the filter will remove all the points that are inside an infinite cylinder that contains the circle + the offset. Inside + Outside: the filter will keep the cylinder that contains the circle + the offset on both sides. Invert : erases the circle + offset. 10

11 Please note that all the points that are along the circle / pipe axis will be taken into account (infinite cylinder): This filter is very useful to clean cylindrical tanks (scaffoldings, pipes ). You can apply this filter on several scans at the same time, even if the circle / pipe was created in one scan. f- Remove scan points along x,y,z This will remove the points that are inside or outside some x / y / z values. This can be useful if you want to keep a slab only, or if you want to delete everything that is before or after a wall. The filter will be applied on the scans selected in the structure tree. 11

12 g- Remove scan points behind planes This will remove the points located behind a plane, or multiple planes, in one or several scans This function has to be used either with our custom planes (see our object manager package), or with the plane creation of Scene. But it won t work with the extend plane function of Scene. Custom plane created with our object manager app: OK. The cleaning will take the limits of the plane into account. But please limit the plane creation to 3 or 4 points, not more. Plane created from a selection, with the inbuilt function of Scene: OK, but this plane is considered as infinite 12

13 Expand plane function of Scene: not ok, too many edges. Workflow: 1- Open the required scans (quickview, planar view) and create one or several plane(s). Use 3-4 points for each plane. If you want to use more points, make sure your polygon is convex 2- Open the plugin, add the planes. 3- Set the offsets (start / end). The offset tells the algorithm where to start the cleaning and where to stop behind the plane. By default, offset 1 is equal to 0 and offset 2 is infinite 4- Select the scans to clean. 5- In case you want all your scans to be loaded and calculated at the same time, tick multithread. Just make sure you have enough RAM. 6- Start the cleaning: the scans will be loaded and cleaned according to the planes selected. Everything that is behind the polygon defined by the planes will be removed. Be careful with the planes created with the inbuilt feature of Scene: they are considered as infinite! Example: 13

14 Before applying the plugin, this is what s behind the wall Step 1: create planes. They can be created in different locations. Make sure the planes are convex 14

15 Step 2: start the plugin, and add the planes Step 3-5: set the offsets (start / end). By default, offset 1 is equal to 0 and offset 2 is 10000m (considered as infinite). If needed, tick multithread. Select the scans to clean. Here, we decided to delete all the points that are 20cm behind the plane and further. 15

16 Step 6: apply. All the scans will be cleaned accordingly to the planes and the offsets selected Result Note: The plugin deletes what s behind a plane from the scanner position. The scanner sees a plane, and what s behind is deleted. You can use the plugin with several scans on several planes. 16

17 However, it will be faster if you do a smart selection of the scans / planes, in order to avoid useless calculation on scans that have no points behind some planes. For example, apply the plugin on the exterior scans first, and then on the interior scans. Tip for creating good planes with our object manager plugin: It is better to create planes with 3-4 points. In case you need to create a plane with more points, please make sure that your polygon is convex: Plane with a convex geometry: OK Plane with a concave geometry: not OK. Some data won t be cleaned 17

18 IV. Known issues Edge and uniform filter: Be careful when filtering a scan created from an existing scan (right click and then new \ scan). Sometimes Scene creates a weird angular range (properties \ scan area), and then the filter fails: all the points are removed. This is independent of our plugin. So, please check the scan area properties after creating a new scan. If you notice a strange horizontal angle on this new scan (example : from 0,5 to 1,1 ), the filter won t work. To avoid this situation, apply the filter on the original scan, then create the new scan, and unload the original scan without saving it. contact@taglabs.fr V. Updates Revision 1 03 August 2017 plane cleaning feature Revision 2 30 November 2017: improved speed and efficiency of the edge filter 18