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Topics - obw

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General / Timelapse for Orthomosaics
« on: February 08, 2018, 06:36:01 PM »
Hi  :)

Does anyone know of any methods/software that can handle such a large amount of data, to be able to create a timelapse video from Orthomosaics? I have a project where I want to have regular flights over the same large area and see the changes over time.

General / Mission planning complex urban mapping with buildings
« on: February 07, 2018, 01:16:24 PM »
Hi there.

I'm wondering if someone have a few tips and tricks on how to plan a mission to scan a large urban area with lots of buildings?

I know this is a complex task, I have experience with regular mapping missions and how to scan and proccess such areas without any complex or tall structures. I've also done some single buildings with OK results. I've tried a few training missions with complex structures and processed some of them, but the models gets a lot of noise. I recon it's the data collected that needs to be better, the workflow in Agisoft is not a problem I guess.

I've read a couple of other threads here on Agisoft, and some guides from other websites, but I'm struggling to find the best workflow for this type of mission. A regular mapping, even with over 90% overlap simply won't cut it. The building facades won't get any points so I need oblique/tilted photos. The problem is how to capture these photos and how close to the buildings. I've tried to add a large circle with angled photos, but this is not enough to get details, and just adds a lot of noise to the model.

Would it be a good way to fly with a slighty forward tilted camera, and fly the mission 2-4 times in diffrent directions? Do I need to circle every single building to get the best results? Or maybe start off with a large circle tilted towards center, and add several other circles towards the center?  I'll attach a screenshot from Google Earth (Even they make good 3D models from urban areas)

General / [Solved] Trouble with GCP marker error UAV survey
« on: January 17, 2018, 12:18:35 PM »
Hi there.

I've been having some trouble with my latest UAV survey work where I've been getting high marker errors on most of my GCP's. I've been searching through the community and found a lot of useful tricks and have optimized my workflow, but unfortunately I got the same results with high errors. The latest attempt was With SAV's optimized workflow ( for UAV survey, which is pretty similar to my own workflow that I've created from your tutorials and community reading.

Aircraft in use:
DJI Inspire 2 X5S 15mm lens. 954 images.

GCS in use:
Leica GS08 Antenna with CS10 hanheld unit, survey grade accuracy. 23 GCP placed.

I've been doing some other projects with this setup without any problems.

It seems like the biggest problem is that the altitude from the DJI photos is not correct. We flown aprox 80m, but the image description says negative 2-4m. But the photos still allign fine so I guess this sould not affect the accuracy as long as we're using GCP? But still, when I add the GCP markers, the errors I get is aprox the same as the diffrence in height (70-75m in error). When I linked the markers to the photos and "updated" the error gets down to a couple of meters, when I hit "optimize" (with standard parameters) the error gets lowered to more normal values, between 3-25cm, but unfortunately most of them above 5cm which is too high. The photos are pretty good, no problems with the allignment and I've removed the bad quality photos.

I'm attaching some screenshots and the report generated.

Thanks for all your help, please let me know if you require more information.

General / Difference True Ortho vs Normal Ortho - Assign images tool
« on: August 16, 2017, 02:13:16 PM »
Hi there.

I found an old topic regarding this matter ( but it didn't give me the answers I was looking for.

Is the Ortomosaics created from Agisoft a True Ortophoto that can be used to measurement purposes?

My model has markers and is georeferenced (NTM10), but when the Ortho is created the buildings does not look good, see attached picture. The distances on the roof edges on the same building can vary up to 1 meter. The ground all looks good. The flight was flown with 75 % overlap in Dronedeploy, while the Agisoft report says a average overlap of between 4,67 - 7,3035.

I've played around with the Assign images tool and it gives me the opportunity to change the image and correct buildings so it all LOOKS Nice, but I have no idea if the measurments are good? I don't know which pictures to choose since some of them are showing the facades of bulidings. If I use this tool - Is the image no longer a "True Orthophoto"?

How do you get buildings to look better in the automated process?

Thanks for all your help, looking forward to hear from you!

Hi there.

How are the exported models with textures actually are working? I've exported .fbx models as DTM with no vertex or texture colors, it opens just fine and no problems.

But when I try to export a DSM model with textures it does not look good. I've exported as .fbx with texture as .tiff. It looks very good in Agisoft when I view it, even if the mesh is not top quality, but when I open in external software it does not look as good. I'm using Autodesk FBX review.

Any ideas?

General / Countour lines edges with no data removing
« on: July 18, 2017, 11:38:11 AM »

I've been generating some posts lately for my project, sorry if this have been posted earlier. Thanks for all Your help!

Is there a way to generate the contour lines without the no-data values, within a polygon or similar? Or worst case to cut the contour lines?

So I have a big Project with 5 chunks and a total of 4-5000 images. The last thing I'm about to create is the contour lines. I've got help from Alexey yesterday that helped me to get good sharp edges to DEMs and Orthomosaics with the shape and Outer line function, but this doesn't help me With the contours.

When I generate contour lines they use the no-data Fields in the edges. This is causing problems in the overlap between chunks because since I've cut the edges of every chunk, Agisoft is estimating the countours (from the DEM) and when I overlap the chunks the results are not good.

So in my model I have cleaned my sparse cloud, my dense cloud, compacted my dense cloud, but still the DEM and contour lines are generated from my original sparse cloud area.

General / DEM edges with no data, from of cleaned dense cloud
« on: July 17, 2017, 10:23:10 AM »
Hi there.

I've cleaned my dense cloud around the borders and used the compact dense cloud function. Still when I create a DEM from dense cloud as source, it uses the entire sparse cloud area as a source, which then results in a DEM with no data around the edges. See Attached example.

Is there a workaround for this? I'm creating 5 models which are overlapping, so I need the edges to be sharp with correct data.

General / Update created models with changes
« on: July 11, 2017, 10:29:45 AM »
Hi there.

We are using Agisoft for mapping purposes.

Is there any way to fly over an area again and only implement the changes to a already created model? Mining, Construction areas etc. Is there a quick way to to this, or do you have to create every model from scratch even after the initial first model?


General / Wrong NDVI scale
« on: July 10, 2017, 10:59:12 AM »
Hi there.

I'm struggling a bit to get the correct scale for my NDVI Pictures.

I can't  understand the "Palette" page in the raster page.  It seems you manually have to adjust the palette to corresond with the correct colors on the NDVI scale between -1 and +1, and not use the auto function. If you use the auto function, the colors on the scale does not allign with the correct values. Then what is the point with the auto function?

Basically what I want is to export a correct color scale that can be used with the exported NDVI orthomosaic.


Hi there!

I'm trying to use the function "Close holes" in my model, but I'm not getting satisfactory results. It's a terrain model taken with UAV Pictures. As you can see in the attached screenshot the hole is right under a Railroad bridge, crossing a road. The area under the bridge was not covered in the photos.

This happend when I classified the model to be able to generate a DTM, which was expected. But I want to be able to Close the hole nicely so it follows the terrain.

Do you have any good ideas? Or other programs that can do this better?



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