Support Website Contact Support Blog

Try out our new tool Pix4Dtagger!

We have a new tool that allows the automatic detection of targets (tags) in images and generates a Pix4Dmapper project file (.p4d) that will use these tags as Manual tie Points or GCPs.

It is meant to be a very useful utility for indoor mapping and for merging automatically difficult datasets.

Feel free to try it and give us your feedback!

You can find the executable, instructions and more information here:

Please note that this is a tool that is under testing. We are working on it to improve it!!

Are you planning on making any updates to this? I do have a couple of questions.

  1. Do you plan on providing more than 10 images?

  2. For a big office building where we need more than 10, can we take multiple data sets and then merge them to create 1 big project? Or will the tags get confused?

Dear Greyson,

Right now, we do not plan on adding more images. However, you can take multiple data sets (projects), and have the tags in each project. You can then process each subproject. To make sure that two different MTPs with the same tag are not identified as the same, you should either change the names in the subprojects, or explicitly say that MTPs with the same name are not the same during the merging procedure.

Best regards,


I am a professional user of PostFlightTerra 3D which is powered by Pix4D.

I had the idea of detecting automatically targets in images. I found your post and I thought : great hopefully it will work !

But every time I try to use Pix4DTagger, it crashes at the end without creating output files (except the folder). Is there a compatibility issue?

Pix4DTagger crashes for me also around 97% completion using the supplied project coordinates text file and images.

I’m extremely happy that Pix4D is catching up with the competition for Automatic Target Recognition.  

Any suggestions on getting Pix4DTagger to work?



Problem signature:
Problem Event Name: APPCRASH
Application Name: tagDetectionStatic.exe
Application Version:
Application Timestamp: 5534e904
Fault Module Name: tagDetectionStatic.exe
Fault Module Version:
Fault Module Timestamp: 5534e904
Exception Code: 40000015
Exception Offset: 00000000002a17a2
OS Version: 6.1.7601.
Locale ID: 1033
Additional Information 1: cd2f
Additional Information 2: cd2f1c3e7d7d929923f41ef04ac648d2
Additional Information 3: 0726
Additional Information 4: 0726115f28d7d8b9d93bbf43542c0c29


Update :

I created a support ticket, and was told to move the coordinates text file to a different directory than the images folder.

This did fix the crashing problem I experienced.  

Thanks !


  1. If the tags are printed to a known size, it would be sensible to have the option of using the tags as ‘scaling units’ in situations where we dont have an accurate GPS available. At least then our scenes would be properly scaled…?

  2. Also, can we have about 1000 of these tags? We can’t easily reuse them as we have many fields with markers that need to stay in place and is confusing to use large number of markers.

3.Could we have an option for tags to all be the same, e.g. white squares. Our tags are well-spaced and we never have two in the same image. So if a list of GCPs is provided, the tag can be assigned to the GCP that is closest to the GPS EXIF info of the image that contains that tag (as long as no other tags are nearby).



Hi Scott, 

Please find the answers below: 

  1. Indeed, if there is no GPS information available for the target, then the target cannot be used as Ground Control Point (GCP) and it will not have an influence on the scale of the project. In this case, as you mentioned, it would make sense to add a scale constraint if the size of the target is known. This article describes how a scale constraint can be added to the project: 
  2. At the moment Pix4Dtagger is compatible with the “Chilitags” library. The latter includes about 1000 different tags. Note that in a single project, each tag should be unique so that the software does not mix-up the different tags. Hence, if some areas do never appear in the same projects, it would be possible to reuse certain tags.
  3. Thank you for your recommendation. We have transferred it to our Product Team. At the moment another approach is used, where each tag would be identified uniquely in a project and the measured GCP coordinates are associated to a specific tag.

For more information about how Pix4Dtagger can be used, we have created an article on our Knowledge Base:


Hi Pierangelo,

The chili tags pre refered library download link is expired

do you have a new one?


Hi @aprflytechstore,

You’re right, the link seems to be down on the EPFL website.

Luckily I found the tags on my computer, so I uploaded them to a shared folder on Google Drive, here you go:

For what kind of applications do you use the tags?


I’ m using Pix4D tagger to include the chili tags inside my projects in mapper