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Warning w9020: GDAL Error <4> DSM Preview.tif:No such file or directory

Has anyone seen this error message before? This project has been issue after issue and was told by Pix Support to start from scratch (purchased a new computer mid project and thought I could simply move the sub projects/merged projects onto the new unit - not the case - thumbnail errors…‘no such file or directory’ errors etc.). I was able to generate an ortho, .LAS files etc. but when exporting the ortho it would only generate corrupted files (the temporary merged transparent ortho file was ~70GB and the final merge was 2.8GB)…So I was forced to start from pretty well scratch. However I am getting this error - which I have seen before - when merging multiple sub projects together.

The last thing I want to do is process this through stage 2 and have this happen to me again… any thoughts?

[Warning]: Warning w9020: GDAL Error <4> C:/Users/User/Desktop/OLRT NORTH/Trillium North/1_initial/report/html/dsm_preview.tif: No such file or directory

I have read multiple posts where the OP is told that the GDAL error won’t impact outputs… I am hoping this is the case. Any thoughts? I am waiting for the merged quality report to generate and will post it ASAP. Frankly I am sure Pix support is sick of me at this point as this project has had problem after problem.


So basically you should not be worried about warnings until the warring is followed up by an error. The GDAL messages should not affect the processing. However, sometimes in the log file, this warning appears just before an error. That’s why it is hard for me to predict the future as I didn’t see your recent processing files.

I took over your personal ticket from the previous agent as he’s currently out of office due to public holiday. I’m going to follow up with you tomorrow (European swiss time) as soon as I review your files. Hopeful we can find a solution.

Could you tell me why it is crucial for you to merge all the titles? Usually, we don’t recommend for very big, merged projects because of optimisation purposes, even in third-party software.


Hi Beata,

The client came back and asked us to incorporate more control for one area based off a laser scan they did of the pump house in the building. I have had to go back and incorporate these points into Step 1 and am attempting to reoptimize the project. One problem I am having is duplicate images - one data set for a section of the project was incorporated into 2 subprojects that were used to merge. I disabled the images in 1 of the sub project but left them enabled in the other. Upon merging the tie points are visible however (i am assuming) that because they were disabled in one project they are no coming up as disabled in the final merge. This has proven to be quite the issue at this point and have since gone back to enable the areas that I need covered (about 10-15 images). It is the same workflow that I did for the previous point cloud/.LAS generation and only found the issue when i added the tie points to the original merged project however upon reoptimizing with the new control for the small building - with all of the images showing disabled - it completely eliminated the tie points for that section. I have gone back and have enabled the images that i need to be able to identify the control and am attempting to merge again. I should have this done in the next few hours and am hoping that the surface will be present in the final merge. Will this impact the ortho generation when I get to that stage? When i ran stage 2 originally (prior to needing to incorporate the control for this area) it seemed to run through smoothly and generate the ortho… I just don’t have the time to go back and complete this work again.

Thanks for the help


I’m going to follow up with you in the personal ticket.