Pixels to Points Help

I am a surveyor and have been using various basic features of GM for over 10 years. I wanted to use P2P to process our drone images for orthoimages and occasionally a point cloud so I upgraded to Release 21 and the LiDAR Module. We flew a job site and I tried to generate an orthoimage. They look like crap. They are blurry, the edges of features are warped- it was useless. A friend ran my images and control points thru Pix4D and they look great- sharp, crisp, perfectly matched our GPS points, good for survey grade images. 

I have ran the same set of images several times using various settings doing the best I can with the instructions in HELP. If I reduce the image size it will run (taking all night but that is not a problem) but the image is useless. If I don't reduce the file size it says it will take 4 days which is also useless.

I know I need training but I live in the hinterlands and to catch a plane to somewhere and go to classes is not optional. GM has always been a favorite software of mine as it has always been intuitive and user friendly. I thought that I would be able to figure it out like I always have.

All my work will be basically the same. We will fly a site somewhere below 200', we will set the Phantom 4 Pro's camera to a high resolution, we will have between 70 & 80% overlap, the sites will mostly all be small- only a couple of acres, we will set ground control.

My computer specs are: AMD Ryzen 7 2700 eight-core processor 3.20 GHz with 32 GB of RAM Win 10 Pro.

To be survey grade I need the orthoimage to be around 0.25' per pixle. Before I give up and move to Pix4D I want to see if someone can help me. Given the parameters and hardware listed above could someone tell me what are the specific settings I need to use for Resampling, create from mesh, reduce image size, relative altitude, incremental/global, quality, camera type. To try them one at a time to find the right combination will take months and patience I don't have. 

Can someone help me?


  • kfroesekfroese Geotechnical Engineer Posts: 182Trusted User
    I feel your pain. I do occasional drone flights (a few a year) and I too have found the resulting orthoimages to be garbage despite hoping for better (also a 10+ yr user of GM). I've had unexplained holes in the data, poor colour matching, and so forth. I've played with numerous settings in GM and rarely have gotten the image noticeably better. Run the same images through Pix4D or DroneDeploy or Carlson Pixelment or Metashape and I always get much better quality and accuracy. Your computer isn't the problem... I don't think GM P2P processing is up to the standards set by those other packages. Price with GM LiDAR is good but, unfortunately, the quality isn't.
  • AlanCAlanC Posts: 4
    GM tech support has been working with me but I don't think they can do anything. I have a side by side comparison of P4D and P2P and, well, there is no comparison. P4D sharp and clear and suitable for survey background. P2P has patches of clear, then a smear, then missing data, warping along all edges, etc. I have to agree with everything you said. A friend told me before I bought it that "they weren't there yet". I bought it hoping he was wrong.
  • @AlanC ;@kfroese have either of you had any better luck with P2P?  I have Pix4D and wanted to start testing P2P and it just seems inadequate for mapping.  

    The main problems I have run into are:
    1. Processing time is pretty long
    2. Can not figure out how to "crop" the image (create a processing area box).
    3. Can not move the ortho image around or zoom without regenerating the Mesh
    4. Can't figure out why there are holes in the map and and the overall output is much smaller than same image set in Pix4D. This is a very small set of images that I am testing with (around 50 images).

    If either of you have any links or other helpful info then please let me know.  I wanted to do some comparison videos between P4D and P2P but I can't even get off the ground with P2P.  

    Thanks for any help!
  • kfroesekfroese Geotechnical Engineer Posts: 182Trusted User
    No, I've given up. One of my other offices has metashape so I send my images there for processing. I given GM P2P as much time as I'm going to until there is a significant rebuild of that side of the software. Good luck!
  • LandskerLandsker Global Mapper User Posts: 8
    Tried P2P when it first came out. Too slow.  Looked again at it after the recent video, again too slow.  I can't say anything about the quality of the finished product as I've always cancelled before the end of the process.  Metashapes is my 'go to' and then export the point cloud to Global Mapper.  I'm also surprised at the increasing ability of Metashapes to manipulate point data, so the file often has much processed detail before it gets to GM.
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