[Tutorial] Extract Google Earth 3D models with Pix4D and PV*SOL premium 2018

http://www.valentin-software.com/serv... 1. Create screenshots in Google Earth Pro 2. Photogrammetry with Pix4D 3. Import of the 3D model into PV*SOL premium First, start Google Earth Pro. For this video I chose a free-standing, relatively complex building in England. Here I enter the coordinates of the object. A 3D model is to be extracted from this object. First, I determine the size of an edge of the model. This is later used in PV*SOL to reproduce the scale. To do this I use the ruler function of Google Earth and draw a 3D path to an edge that is well visible. The measured length of the edge is approx. 20m. In the next step I will take about 30 - 40 screenshots of the scene to create a 3D model in Pix4D. In order to achieve an optimal result with photogrammetry, all labels and menus should be hidden first. Now the screenshots can be made. Recommendation: take pictures at 3 different altitudes: 12 pictures at the height of the ridge or the highest point of the building. 8 pictures from different angles of the bird's eye view 12 pictures at a height of 3 meters Make sure that the target building is always completely visible, that potential additional shading objects are visible, and that the pictures are not too twisted. The more images that are created from different perspectives, the better the 3D model created later on will be. In some photogrammetry programs it is useful to take some close-ups as well. Also move the mouse out of the picture before creating the screenshot, so that the mouse cursor is not visible in the picture! After you have made the 30-40 screenshots, start Pix4Desktop. (…) In the next step the screenshots will be added. Click on "Add Images". Now select all screenshots with "Ctrl-A". (…) Select the menu item "3D Models" and then click "Finish". The map view is now displayed. This is not interesting at the moment, because there is no geoinformation in the pictures. The next step is to create the 3D model. Before I click on "Start", let's first look at the options for this. Click "Process", and then click "Process Options". At first, only the settings for "Process" and "Point Cloud and Mesh"are interesting. I leave the general process options unchanged. Make sure that "Keypoints Image Scale” "Full" is selected. You can experiment a little later on with the settings for the "Point Cloud" to get an even better result. I leave the settings unchanged. A few things have to be adapted to the mesh options so that the 3D model can be imported correctly into PV*SOL premium later on. I want the textures from the screenshots to be transferred into the 3D model. The maximum "Texture Size" should be 4096 pixels. The maximum number of triangles has to be limited for the level of detail, because PV*SOL premium currently only accepts 3D models with a maximum of 500,000 points. You can achieve this with the decimation strategy "Sensitive". A model file is automatically generated after photogrammetry is complete. Here you specify that this file is to be created in obj format. Now the 3D model can be created. First, perform step 1 only! This process can take several minutes. I'm fast-forwarding. The result now shows the reproduced positions of the camera and the tie points. The camera positions can be hidden. Unfortunately, the program sometimes has difficulties in determining the correct position of the model from the screenshots. Here you can see a completely unnatural slope which has to be corrected. The "Orientation Constraints" function is used to correct the alignment and inclination of the model. Place the ends of the 3D arrow at a distance you know to be parallel to the height axis. (Here z-axis!!) Step 1 must now be revised. The model has now been corrected. Next, the triangle mesh can be generated. I'm fast-forwarding again. ;) Now the 3D model is already complete and can be viewed. If you want to view the mesh, you must first activate "Triangle Meshes". I just want to view the triangulated mesh and disable the other elements. You can see that the 3D model is already close to the Google original. Now open PV*SOL premium 2018 or a higher version! I am already in the 3D visualization of PV*SOL premium and have started a new project there. Now import the 3D model you created with Pix4D. To do so, click this button. You will find the. obj file, as well as materials and texture in the project folder that Pix4D has created. I simply place the 3D model in the middle of the terrain. As you can see, the 3D model is stored in an unusual coordinate system, which has to be corrected. To do this, double-click on the model and select the "Tilt backward" option. The model has also been well imported into PV*SOL premium. Here already with representation of the shading. (…) End of the tutorial.