Rendering Geotiff (DTM and DSM)

General Help
#1

Hello everyone, I got WebODM two weeks ago for processing some drone data and I’m suprised by the functionalities and results obtained with my datasets.I would like to know what is the kind of approach that ODM uses to render the Geotiff in the front-end.

Thanks in advance

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#2

Welcome!

Glad you like it!

I believe we’re serving a Cloud-Optmized-GeoTIFF using HTTP Range Requests to “tile” it into the WebODM webmap display.

Or did you mean something else?

2 Likes
#3

We use a fork of rio-tiler to render GeoTIFFs (plus some code to expose it via django, add plant health algorithms, elevation renderings with shading, etc.).

It’s all here: WebODM/tiler.py at master · OpenDroneMap/WebODM · GitHub

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#4

Hello Pierotofy, thanks for the information. Do you have any sample that you can share to learn more about this?.

Btw I was reading the introduction book on WebODM, and I have one question related to the camera parameters calbration. I would like to use these parameter in a json file during the processing.
The camera calibration data is imported from DJI XMP meta data (Drone Phantom 4 RTK)

p4fx = 3715.17
P4fy = 3707.50
p4cx = -52.35
P4cy = -25.32
P4k1 = -0.284494
p4k2 = 0.13576
p4p1 = 0.00123282
p4p2 = 0.00000143892
p4k3 = -0.047753

sensor width = 13.1328
sensor height = 8.7552
pixel size = 2.4

I’m have some issue importing the json file in WebODM (below), I did take as an exmaple the json file created by WebODM and replace the values.

{
“dji fc6310r 5472 3648 brown 0.6666 rgb”: {
“projection_type”: “brown”,
“width”: 5472,
“height”: 3648,
“focal_x”: 3715.17,
“focal_y”: 3707.50,
“c_x”: -52.35,
“c_y”: -25.32,
“k1”: -0.284494,
“k2”: 0.13576,
“p1”: 0.00123282,
“p2”: 0.00000143892,
“k3”: -0.047753
}
}

Thank you in advance for your help

Jefferson Benitez

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#5

Hello Saijin_Naib, Thanks for replying my message. I did spend the weekend looking to COG and the libraries that allow to use the approach. I did discover GDAL library that allow to create the files. I did use this https://cholmes.github.io/cog-map/#/center/-133.817,68.8/zoom/5 to visualize them. I will look at the rio-tiler to render GeoTIFFs as well.

Have a good day, thanks

Jefferson Benitez

1 Like