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linear job problem

Again I fell frustrated.
Before I did this job, I created test mission - Linear Job, 10m/s flight, 60m AGL with 2sec photo-interval. What I achieved with your tool was not only orthofotomap, but also full 3D Model. You can find it here: https://www.mapsmadeeasy.com/maps/detail/b3b9f8654f8d46f8851dbe73ead50dcb/
 
Then, I made my target flight - also Linear Job, 10m/s, 60mAGL, 1 seconds photo interval. Difference? A lot larger area.
Results? NONE.
 
And now you are telling me that:
1. We require AT LEAST 3 passes for linear jobs. This has one single pass which absolutely doesn't work. 
2. Also, Full 3D processing only works with 80+% overlap in both along track and across track directions. Once pass will give no result.
BOTH ABOVE were definately enough when I tested you in demo mode. But after I paid you, I waited 30hours for zero result. Why?
Jakub

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We are sorry to hear you are frustrated. You didn't mention anywhere in your previous post or emails that you were doing a single pass linear mission or you would have been steered properly.

https://support.dronesmadeeasy.com/hc/en-us/community/posts/360076076852

The following has been part of our Data Collection guidelines which are agreed to at the time of upload for years:

From https://www.mapsmadeeasy.com/data_collection

  • Job Shape - When doing long, linear jobs, make sure to do AT LEAST three passes so there are enough perspectives to reconstruct the scene. Increased overlap will need to be used to make up for the lost width. When doing few passes don't do a straight line. Either put a kink in it or use more passes.

Also, you were trying to map a 4.3 kilometer linear area at 1 cm/pixel which violates the Maximum Resolution section as well:

  • Maximum Resolution - Take the size of your survey area and divide that by your GSD estimated GSD. If that is over 200k pixels in either direction you will need to break it up.

The file you were trying to make was over 400k pixels. That is not possible in our system without making special arrangements. 

All jobs are charged immediately because the user attests at the time the data is uploaded to process that it follows the guidelines. If you upload something that is not within the system's capabilities it is going to fail. That is why the guidelines are there: to help you have success. 

Yes, it initially worked for a 21 image sample but you are lucky (or unlucky) that even turned out. If you don't have multiple passes of data you would need to use 95% overlap to get the proper amount of looks at everything that needs to be processed. 

Our system tried to process your data for 30 hours before giving up because the data was insufficient. 

You cannot expect good results if you do not follow the guidelines. Some things take some practice to get right and understand so making incremental changes makes sense when learning something new so you can find out where the boundaries are. Consider this a cheap learning experience for yourself. It cost us far more... 

 

Zane
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The follow result was achieved using our new Flat Map system (beta) at quarter resolution in 18 minutes:

 

Zane 0 votes
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Zane, thank you.

Can we have any output from my dataset?

I can shorten my path (let's say cut it by half or even 75%) in order to have anything so I can show my client that I'm working.

If it worked for 21-pics sample I can reduce my input to 80/60/40 or even 20 pics. 

Jakub 0 votes
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What you sent in outoput-preview is showing that something indeed has been processed.

Jakub 0 votes
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OK, I posted two jobs by myself.
So the initial 287-pics job was not successfull as you mentioned the reason that (long story short) :(1) I prepared bad flight plan. Second reason was  that (2) I posted too large area which is not possible for you to process.


regarding #2 - I think that it should be your scripts to check what area size I'm posting to check if I create any problems for your software to complete the task. In that case I would not be charged for what you can not do for me :)

regarding #1 - after I limit my dataset from 287 pics to 38 & 83 pics in two jobs, processing finished without ANY errors. I can see some artefacts, and interruptions in continuity of my ortophotomap. But tasks finished succesfull, and full 3D model has also been created, not to mention it was posted to Sketchfab.

 

Jakub 0 votes
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#2. There really is no way to tell how big it will end up being until it is done processing. We make that guess internally but try to process it anyway since the user is telling us it is OK. 

The smaller jobs you processed only had a few images get processed into 3D outputs. The rest of what you are seeing is the Flat Maps Failover system. 

https://support.dronesmadeeasy.com/hc/en-us/articles/360054457952-Flat-Map-Failover

That happens when the data is not sufficient for 3D processing and 3D outputs are not provided. It is not perfect data but it is better than nothing sometimes. This system became active on 1.1.21.  

The 3D products that were created were only of a few images that had enough overlap to process. Your single pass data actually had gaps in it which also made it violate this part of the Data Collection guidelines:

  • Contiguous - All images must share a common boundary. Don't upload non connecting sections or separate islands of coverage.
Zane 0 votes
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OK, thx for detailed explanation.

Will have to learn more.

Cheers

 

Jakub 0 votes
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