Pix4D Mavic 2 Processing Issues

PIX4Dmapper PIX4Dmapper Questions/Troubleshooting
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Edited on January 24th 2019

 

A new firmware update for DJI Mavic 2 was released on 2018.10.11 (v01.00.01.00) and the latest status regarding the geotags is the following:

  • GPS Altitude  written in the EXIF file of the images  is correct. 
    Exif.GPSInfo.GPSAltitudeRef   Above sea level
    Exif.GPSInfo.GPSAltitude        376.6 m
  • Latitude and Longitude  written in the EXIF file of the images  are not correct.
    Exif.GPSInfo.GPSLatitude       46deg 30’  - 24.216"
    Exif.GPSInfo.GPSLongitude      6deg 32’  - 17.914"

 

At the moment, I would recommend  updating the firmware  version of the DJI Mavic 2 Pro and apply one of these three workarounds:

1.- For those who use Pix4Dcapture for image acquisition.

  • Performing the mission with Pix4Dcapture (iOS) flight planning app produces a project file ( .p4d ) when downloading the images to the device, also called Synchronization. 

After successful synchronization, the .p4d file and images can be extracted from the mission folder when connecting the mobile device to a computer or by directly uploading the project on the cloud. 

This project file (.p4d) includes correct coordinates of the images and will position the images correctly in the project. For precise georeferencing, I recommend using GCPs. 

2.- For those who do not use Pix4Dcapture.

 - 2.a Pix4Dmapper 4.4.9

A new Pix4Dmapper preview version has been released (on January 24th, 2019)  which reads the image geolocation from the XMP tags instead of the EXIF tags.  This only applies for  DJI drones  (Including Mavic 2), for all other drones, the image geolocation will still be taken from the EXIF tags.

In case of DJI drones, the exact tags which are taken are:

  • Xmp.drone-dji.Latitude

  • Xmp.drone-dji.Longitude

  • Xmp.drone-dji.AbsoluteAltitude

More information about EXIF and XMP tags can be found here: EXIF and XMP tag information read by Pix4D

Please note that the altitude can still be inaccurate. From our experience, the correct altitude when it comes to DJI drones is most of the times written in the Xmp.drone-dji.AbsoluteAltitude but it is sometimes written in the Xmp.drone-dji.RelativeAltitude tag. 

Our recommendation is to check the coordinates in the Image Properties Editor  before running the project.

 - 2.b BR`s EXIFExtracter

There is a freeware programme called _BR`s EXIFExtracter (_which can be easily downloaded here) which is able to create a .csv file including the GPS coordinates read from the XMP tags.

The steps to follow are:

  • Open the software
  • Select the folder where the images are located
  • Select the name and folder where the .csv file will be saved
  • Select the data to be exported: GPS latitude, GPS longitude, GPS altitude.
  • Click on export

Best,