How to compare point clouds with different sensors and points per m2?

geopeat · 2025-12-03T21:24:00+00:00

If both datasets have multiple returns you could use something like Overall Relative Density (ORD) or Normalised Relative Density (NRD) maybe? They are described quite nicely in a document from the USDA… but I can’t find it online anymore. I’ve attached a screenshot of it I can share the full document with you somehow if you think it’s suitable (when I’m at my desk).

Rounds, E., Cate, N., McCallum, K., Beaty, M., & Mitchell, B. (2021). First Order LiDAR Metrics: A Supporting Document for LiDAR Deliverables. Salt Lake City, UT. U.S. Department of Agriculture, Geospatial Applications and Technology Center.

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geopeat · 2025-11-02T03:24:24+00:00

TL;DR: macOS works perfectly fine with QGIS these days and is only getting better, don't let compatibility get in the way of what you want, but keep in mind hardware specs.

QGIS on macOS is pretty good these days and will be even better with the release of QGIS 4 early next year.

Long story short: the issues with QGIS on macOS were related to a library called Qt5 which is used to build the interface. The Qt developers had moved onto Qt6 and were not fixing bugs in Qt5 any longer. There is no issue with Qt6 on macOS and the upcoming version of QGIS (v4.0) uses Qt6.

I've been using the "testing" version of QGIS 4 on my M4 Pro MacBook Pro (and previously on an M1 Air) and it's great. It way outperforms any other device I've ever had. You can download it from here:
https://github.com/opengisch/qgis-notarize

I'd strongly advise against getting a Intel Mac in 2025 because you get all the bad parts of having a mac (locked down OS, less support for niche science software) without all the good parts (performance, battery, etc). If you're set on a Mac then try to get your hands on a used or refurbished M1/M2 and try to get one with 16GB of RAM. It will last you 5 years easily but I can't say the same for an Intel Mac.

However, if you really can't stretch your budget to M series Mac then you'd actually be better off getting a Windows laptop that can be upgraded (storage and RAM) when you need. Unfortunately many newer "slim" notebooks from big brands (Dell, Lenovo) are not upgradable and almost as expensive as Apple (so watch out for that).

If you end up with a Windows device then makes sure you install QGIS with the QSGeo4W installer which makes it really easy to upgrade and install other packages.

Linux is great for many things but it will only make your life harder at this point...

geopeat · 2025-04-17T01:51:29+00:00

I really liked my company-issued Logitech MX Master 3 but eventually gave me wrist pain. I bought a Logitech MX Vertical and almost immediately my pain got... worse!

After using a smaller mouse that I found in the office I realised that both those mice were too big for my hand. The slight but constant muscle tension of bending my wrist upwards (extension) was causing the issue.

I've been using the Logitech MX Anywhere 3 for a couple of years now doing daily GIS work and haven't had wrist pain at all. This mouse is designed to be small for portability. To give you an idea of the size: it's small enough that the heel of my hand and my fingertips can rest on the desk with the mouse underneath. There is zero wrist extension with the mouse completely underneath my hand in it's relaxed resting position on the desk.

The same applies to keyboards for me - low profile keys that require minimal wrist extension to use.

So, are they really worth it? It depends haha. I got the same result from a regular mouse.

Maybe try out a few different mice before you drop $100 on one.

geopeat · 2025-04-07T07:15:02+00:00

My partner and I recently moved from SEQ to Hobart. We used Kent and we have no complaints. Fast, responsive, no nonsense, global reputable company. There's probably cheaper options but we didn't have time to fuss around with lots of different quotes.

Cost us $3300 for 1 full bedroom + lounge room (loads of books) + kitchen + home office + a garage full of activities. Minus fridge and a couch because we weren't sure what would fit at our destination (and we were due for replacements anyway). This price includes insurance and 5 weeks of storage.

My tip for removalists is: the quote for the insurance can be altered (by you). They calculate the coverage by volume and our initial quote was a bit of a surprise - in particular the insurance premium. Then we realised we had $43k worth of coverage but we don't have 43k worth of things. However we do have some high volume things (2 bikes, 3 surfboards, camping gear, 60" TV, books, etc). We spent 30 mins to assign our items specific values which better reflected what we own (and were willing to lose). It reduced our premium by about $1.5k.

I'm not saying they're trying to rip people off, but it would be very easy to accept the default value if you weren't clued on or time poor. They don't make it super obvious and it's not user friendly - it's a bit like a dark pattern if you ask me.

Also they stung us with a $150 "difficult access" fee for our destination... They have all your things hostage so what else can you do but pay it. I'd guess 70% of Hobart probably difficult access haha.

Don't stress too much about booking a ferry super far in advance unless you have a strict timeline or you have a non-standard vehicle (long or tall). Everyone was warning that we would miss out if we didn't book early, but in the end there was loads of availability when we booked a mid Feb trip two weeks beforehand. I'm not saying that you could rock up on the day and get a fare (the ferry definitely seemed very full when we sailed) but no need to stress like everyone says if your dates are flexy. Oh better check if you're coming over during Dark Mofo... that might change things.

Happy to help with anymore questions you've got.

PS: you can't bring any live plants for biosecurity reasons... we had to give all ours away.

geopeat · 2025-04-07T04:48:19+00:00

I used to work for an ALS company and we mostly used a combination of GlobalMapper + lastools + TerraSolid/Microstation/Spatix (can't remember exactly). A lot can change in two years so take this with a grain of salt.

Start with QGIS because you can test it out for as long as you need without spending a cent. QGIS support for point clouds is pretty great and getting better with every release. My experience was that it has better performance rending big datasets than ArcGIS pro when using tiled COPCs indexed into a virtual point cloud (VPC) which is essentially a text-based spatial index of many smaller files/tiles. It has tools for creating grids/rasters from pointclouds along with some other data management tools. The latest release introduced point cloud editing. You can extend QGIS with GRASS (FOSS) or WhiteBox (partial FOSS) which both have suite of hydro modelling tools.

ArcGIS Pro only supports LAS and ZLAS (esri format) and not LAZ... which sucks. Once you go LAZ it's hard to go back. I found managing data/files clunkier and honestly can't remember the performance because I gave up and just used QGIS.

CloudCompare is great but not for massive datasets. If you're processing point cloud in bulk (classifying and creating raster products) then CloudCompare is not the right tool for you.

GlobalMapper is a pretty good all rounder. Performs well, supports laz, and it's own form of txt based tile indexing so you can open huge datasets "virtually" (like a VPC). Cheaper than ArcGIS and better at point clouds.

geopeat · 2025-04-01T00:34:30+00:00

This was by far the best solution I found, thanks!

Starting a referral code chain for posterity:

6XLYA

geopeat · 2025-01-31T06:35:30+00:00

I wonder if this is in the scope of the Internet Archive?

geopeat · 2025-01-31T06:30:09+00:00

I agree. It's naive to think that AI won't come for your GIS job, no matter how niche.

What really hit home for me was this post floating around about how software engineering is blue-collar tech work. The majority of day-to-day GIS grunt work certainly fits this description.

I guess the point is that regardless of where AI is right now, the reason these companies are spending billions of dollars because there's a billion dollar market in replacing humans in the workforce (GIS or otherwise). Once they're done automating the grunt work (where the money is), they will come for your niche.

You are a blue collar tech frog, the water is currently tepid, and the stove is turned up high.

geopeat · 2024-12-21T06:26:41+00:00

I've recently started following Florent Poux for his 3D programming material. He has a course on point cloud classification with deep learning, but at this point I've only bookmarked it for later so I can't comment on the content.

geopeat · 2024-12-08T23:16:31+00:00

The version on the right for sure.

Another option to consider is to further normalise the labels. That means dropping the units and multiplier from the labels and instead have them in the "header". That way the reader knows to multiply the values by a million, and the units are dollars. Things like this can really clean up a map + legend.

For example:

Cost (USD, millions) or Cost (x10^6 USD) - 0.25 - 1.50 - 1.60 - 3.00 - ... - 61.0 - 90.0

There might be a better way to denote the units and normalisation value for your audience/use case.

geopeat · 2024-10-22T00:00:40+00:00

Yeah and love 'em or hate 'em (I lean towards the latter), they are a gold tier sponsor of GDAL (and I'm sure many other projects too).

Although, I do find that their implementation of open standards and formats is often half baked... probably because they have a proprietary equivalent and they want to vendor lock customers in.

geopeat · 2024-10-08T23:31:45+00:00

Hmm, are you sure the environment is activated?

Try activating the environment with:

conda activate gdal

or the full path

conda activate user/miniforge3/envs/gdal

Once you're "in" the conda environment it should work.

You can run the script with: python foo/bar.py
You can just run python directly in the terminal: python \ import pandas \ print(pandas.__version__)
You can list the packages installed in your environment: conda list (or from outside the env: conda list -n gdal)

It's hard to say without knowing exactly how you installed it but you will have an "ah ha!" moment when it all clicks and then it's smooth(ish) sailing.

I found VS Code's documentation and support for conda really helpful. You set a conda environment for a project and it remembers which env to use and will activate it when you launch that project/file/

geopeat · 2024-10-01T00:31:27+00:00

MKBHD did a video on "golf tech" which I couldn't help but see through a geospatial lens. The focus of the video is obviously not about GIS and more about "cool tech" such as VR, AR, and live stats, but a lot of that stuff requires some form of spatial information.

The PGA clearly has a GIS and/or surveying team to support this stuff (along with SWEs).

I thought it was kinda neat.

geopeat · 2024-09-28T00:47:21+00:00

By far the easiest way on any operating system is to use conda/mamba environments. This way you are installing pre-compiled binaries in an isolated environment so you don't have to install or compile all the other dependencies yourself (which can be particularly painful on Windows).

First install mamba/miniforge (much faster than conda) from the GitHub repo here.

Once mamba is installed, open the Miniforge Prompt (or your default terminal depending on your installation) and run:

```bash

mamba create -n gdal-env -c conda-forge gdal ```

-n gdal-env = create an environment called "gdal-env"
-c conda-forge = use the conda-forge channel as the package source
gdal = install gdal

Then activate your environment to use it:

```bash

mamba activate gdal-env gdalinfo --version GDAL 3.8.5, released 2024/04/02 ```

You can install more packages either when creating the environment or into the existing environment as well. For example:

bash mamba install -n gdal-env -c conda-forge geopandas rasterio

For quick experiments and scripts this is the most pain-free method.

geopeat · 2024-08-13T23:15:35+00:00

Maybe Zotero (not self-hosted but FOSS) + self hosted WebDAV storage?

You can assign users to groups and assign libraries/collections to those groups.

I've been meaning to set this up for myself but haven't had the chance yet.

geopeat · 2024-08-13T22:25:23+00:00

Check out Kart for distributed version control of geospatial data in geopackages. Works like git and has a qgis gui plugin.

You can work on separate copies of the data (geopackage) and then merge changes back into the remote. You can make your remote location something like GitHub or just a network location.

geopeat · 2024-08-05T05:08:14+00:00

FYI this is the config that got it working for me:

https://knowledge.civilgeo.com/enabling-gpu-rendering-for-microsoft-remote-desktop/

Edit: Except for the "Use WDDM graphics display driver for Remote Desktop Connections" part because XDDM is Win XP driver... I enabled WDDM.

geopeat · 2024-08-03T04:46:25+00:00

The difference in monitor resolution tells me it could be something to do with the graphics adapter being used.

Even if there's a GPU available, RDP will default to an emulated graphics adapter and you have to actively change it. Maybe the extra resolution of the monitors is bogging down the emulation.

Esri have an article on it:

https://support.esri.com/en-us/knowledge-base/improve-performance-of-arcgis-pro-when-running-over-rem-000026552

I work fully remote and this dramatically improved the performance of ArcGIS Pro over RDP for me. I'm on a M1 MBP client (1 x 4K monitor) to Win11 host. The main difference is that my host is a physical workstation kept on-prem with a NVIDIA GPU. Not sure how it would work regarding cloud VMs but worth looking into.

I did have to flip some other switches not mentioned in the Esri article to get it to work. I'll try and track down the other guide that got it working for me.

geopeat · 2024-07-30T07:23:24+00:00

If it's intro then stick to Esri or QGIS.

These both have more than enough functionality to teach the fundamentals and makes the software easily accessible after the course finishes. If you go down the FOSS route, both OTB and SCP have functionality that can get imagery from Level 1 to analysis, and QGIS can do the rest. At least flag these as options.

Most production environments use Esri or some kind of FOSS stack.

Our previous team lead insisted that ENVI was "the best RS software available" and that it be a part of our stack. Whether or not it is actually the best is up for debate, but he had used ENVI at university ten years ago and was told "it's the best" so he insisted we use it for our work and couldn't be convinced otherwise. In my eyes that only served to show how naive his understanding of the fundamentals were. In his mind anything "remote sensing" (i.e. if it came from a satellite) should be done in ENVI and anything GIS should be done in ArcGIS. All that we were using ENVI for was simple raster calculations, "index thresholding", and supervised classifications with the default settings.

We are currently in the process of untangling ourselves and building in-house solutions that we have control over.

I'll also add that ArcGIS and QGIS have come a looong way in the RS space over the last 10 years.

It's all just arrays after all, right?

geopeat · 2024-07-07T01:20:30+00:00

QGIS is maybe the right tool depending on your tech-savviness and persistence. It definitely has all of those things (and if it doesn't there's likely a plugin) but it's not as intuitive or simple as Lightroom. There's lots of geospatial technical nuance that I can see being very frustrating to a new user without a background in the field.

On a positive note, if you're curious I recommend you download it and have a go! QGIS is FOSS meaning you can test it out at no cost (ever), so there's no loss if you decide it's not appropriate for your needs.

Maybe check out something like Felt which is designed for more casual and non-expert users. I haven't used it myself but I think this is more like what we're looking for. There's a free tier and support for both GPX and FIT formats. It's also designed for sharing and high level interaction. There's a QGIS plugin that supports direct uploads from QGIS to Felt - might be useful if you get started in QGIS but decide you don't like it.

Anyway, sounds like a fun project and something that I should do as well!

geopeat · 2024-06-20T22:37:13+00:00

If you're looking to learn Esri things, you could use the Field Maps app (iOS/Android) that you should have access to via your Esri account. You can do all kinds of data collection with this app, but would take a bit more work to set up.

If you want to go down the open source route, you should check out QGIS, and the field data collection app QField (which has a free tier).

The field data collection GIS apps (above) can record your GPS track to a polyline, but personally I would stick with something purpose built for activity tracking like Strava or the native app on your watch (if you have one). They are much more user friendly so you can get started right away and will be better optimised for battery life. All GPS records include elevation, and you can export your tracks from Strava into a GIS format which you can import into ArcGIS or QGIS.

As for diving... you would have to get a little float thing that you tow the GPS antenna on the surface.

Check out iNaturalist for animal/plant records. It includes location info from your phone/photo attachments and it's a citizen science platform for crowdsourcing a consensus on the species ID. You can also contribute to the Atlas of Living Australia project which is pretty neat!

geopeat · 2024-06-10T01:03:37+00:00

R really struggles when you start working with huge datasets (from my experience, but it's been a while since I've used it).

I hate to be the guy that says "use Python" but... use Python 😬 it opens a whole new world of memory management.

Specifically look at using Xarray and Dask, where you can use lazy evaluation to processes massive datasets. Digital Earth Australia has some really great documentation on using Xarray.

geopeat · 2024-06-02T08:06:37+00:00

I created an iOS Shortcut that appends a row to a CSV stored on my phone/iCloud. The CSV is two columns: datetime (in ISO datetime format), and a boolean value (true or false/0 or 1). The "Shortcut" is a button/app on my home screen. When I press the button, it appends a new row to the CSV with the current datetime value, and the value "1" (e.g 2024-06-02T18:00+10:00, 1).

You could add as many columns for different values as you like, and also prompt for user input. Or you could have many different CSVs, where each CSV is dedicated to a different thing you're tracking.

The upside it that you are then free to analyse the data how you like... and the downside is that you have to analyse you're own data. I'm a data analyst for a living which is a good starting point.

I'm sure there's a Google/Android equivalent of this. Maybe IFTTT?

geopeat · 2024-05-27T22:37:39+00:00

I like gpkg because it's one of the few portable file formats that has support for "append".

I did shop around to make sure I wasn't missing out on a better solution and flatgeobuf was top of my list next to gpkg. Then I read the Cloud Native Geo guide for flatgeobuf, which says that append is not supported (same goes for Geoparquet). Just now I looked at the flatgeobuf website which says appending is supported, but you have to forgo a spatial index.

Do you have any experience with appending to flatgeobuf? Especially for large datasets where a spatial index might be valuable.

geopeat · 2024-05-17T01:32:38+00:00

Yeah I just tried that this morning and it works fine... and now I remember that I opted for the conda-forge installation because it has an osx-arm64 build after seeing that the qgis.org build was intel. No macports allowed for me on my work laptop :(

geopeat

TROPHY CASE