Forum

Author Topic: Added Erosion radius option to Classify Ground Points dialog  (Read 1379 times)

Paulo

  • Hero Member
  • *****
  • Posts: 778
    • View Profile
Added Erosion radius option to Classify Ground Points dialog
« on: October 12, 2021, 09:24:50 PM »
Dear support,

in latest release 1.7.5, there is Erosion radius option in Classify Ground Points.

Could you explain what this option does?
Best Regards,

Paul Pelletier

c-r-o-n-o-s

  • Jr. Member
  • **
  • Posts: 78
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #1 on: October 13, 2021, 11:45:48 AM »
*irony on*

Have a look at the manual.

*irony off*

(Such software with so many complex settings really deserves better documentation.)

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 13222
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #2 on: October 13, 2021, 07:47:08 PM »
Hello Paul,

Erosion radius determines the indentation (in meters) from unclassified points, ground points within that area will be unclassified. This new option may be useful when classifying areas with houses and trees to avoid "stumps" on DTM when building elevation model from the ground points class.
Best regards,
Alexey Pasumansky,
Agisoft LLC

c-r-o-n-o-s

  • Jr. Member
  • **
  • Posts: 78
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #3 on: October 13, 2021, 08:55:10 PM »
That is of course a very good approach!
For the classification, I still prefer the approach where the terrain is evaluated "from below".
This way there are no "stumps".

I often classify terrain on slopes, where Metashape has problems, but I'm going to try out the new version.

Paulo

  • Hero Member
  • *****
  • Posts: 778
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #4 on: October 14, 2021, 01:05:43 AM »
Alexey,

it would be good to give examples of different values of parameter and its effect on classification....

I tried using erosion radius of 0.2 on a cloud and result was worse than no erosion radius or 0....

Hope to get more clarification on this potentially useful parameter,
« Last Edit: October 14, 2021, 05:35:50 AM by Paulo »
Best Regards,

Paul Pelletier

CheeseAndJamSandwich

  • Full Member
  • ***
  • Posts: 121
    • View Profile
    • Sketchfab Models
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #5 on: October 17, 2021, 05:13:50 PM »
*irony off*

(Such software with so many complex settings really deserves better documentation.)
This is a very, very important point.

We're lucky that we do have a these forums, and Alexey, etc, helping out in most posts... But the documentation is OK in most areas, and 'lacking' in many.
This is a complex application doing so many different things, with lots and lots of features, that help us in so many ways...  But so little is written about some of them.

We're also blessed with an astoundingly easy workflow that works so, so well out of the box, so we can get epic results with almost no effort or experience with the software...  But the devil is in the details...  When things don't quite work as hoped, when we need to go the extra miles to get the very accurate results demanded by the job at hand, then we have to get dirty and get technical, using all the little special  features that do very specific things...  Part of it is knowing how to use them... bit a big part of it is knowing that they exist in the first place!!!

As with any complex software like this, if you have good documentation, and a good user community, then the software can be very easy to use and get the job done, meaning that it'll get adopted by more and more of the industries that need it.
The easiest to use, most well documented, most supported software will win over the complex unsupported ones, even if they're match in ability.


Some things that would make Metashape better:
  • Tooltips:  Tooltips are amazing!  And familiar to us all.  MS uses them already for the toolbar buttons, but it could use them a LOT MORE?  Tooltips be added to every setting in the preferences dialogs (which is a common place for them) defining the setting and suggesting values.
    Could they also be added for all the menu items?  Not just the toolbar buttons?  Not that common, but still very, very desirable.
    The tool tips should be an explanation of the feature, and if possible, with perhaps a few notes on applications, suggested values, etc.
    As tooltips appear after a delay, even a long explanation, or lots of details about it, would not affect the usage, experience by the user, it won't get in the way.  If you pause, you get a good explanation.  If you know what you're doing, they proably don't get enough time to appear.
    Flesh these tooltips out, and enable them everywhere!
  • Example scenarios:  In the manual, it would be great if a lot of the features had examples of where it could be used, and how it would be used for different uses of MS... So there would be examples for aerial/drone work, examples for turntable rigs, for interiors, etc, etc. where the settings might be different for the different uses.
  • Crowd-sourced explanations and examples:  Perhaps the users that have gained a lot of experience with MS could submit their settings and insight about various features, say as concise case studies.
    It could even be that each time Alexey fleshes out an explanation of a feature for us, after a forum user posts, then we could take that explanation and submit it in a 'Tooltip' format and a revised Manual entry.  The documentation would then grow as a when features are asked about and explained.
  • Workflows:  One of the most useful, educational, and even reassuring documents, is the USGS Processing Workflow.  Probably one of the most valuable resources to a lot of us.  It tells us what, when and why, to get the outputs they needed.
    If we could get a collection of these, submitted by us users, for all of our different use cases, then that would be absolutely amazing, so useful.
    Each workflow could then be critiqued by us peers and the devs, and then perhaps updated as we learn new things, new features come along.  The author optimises their workflow, we all learn from their workflow.
    Having a few different workflows for your type of use case would be great.  Some for drone surveys, some for underwater surveys, some for scanning archaeological sites, or museum specimens on turntables, scanning cars, etc, etc, etc...
    This would allow any new user to get up to a reasonable speed, very, very quickly!

Fleshing out good quality documentation, manuals, etc is not easy, it's very time consuming, and needs maintaining... The devs are busy enough coding new features and making MS faster... But it's very, very important...  If it can be improved, it absolutely will help us all...  And the easier to use software will ultimately sell more copies.

Paulo

  • Hero Member
  • *****
  • Posts: 778
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #6 on: October 17, 2021, 06:25:16 PM »
Quote
This is a very, very important point.

We're lucky that we do have a these forums, and Alexey, etc, helping out in most posts... But the documentation is OK in most areas, and 'lacking' in many.
This is a complex application doing so many different things, with lots and lots of features, that help us in so many ways...  But so little is written about some of them.

We're also blessed with an astoundingly easy workflow that works so, so well out of the box, so we can get epic results with almost no effort or experience with the software...  But the devil is in the details...  When things don't quite work as hoped, when we need to go the extra miles to get the very accurate results demanded by the job at hand, then we have to get dirty and get technical, using all the little special  features that do very specific things...  Part of it is knowing how to use them... bit a big part of it is knowing that they exist in the first place!!!

As with any complex software like this, if you have good documentation, and a good user community, then the software can be very easy to use and get the job done, meaning that it'll get adopted by more and more of the industries that need it.
The easiest to use, most well documented, most supported software will win over the complex unsupported ones, even if they're match in ability.


Some things that would make Metashape better:
Tooltips:  Tooltips are amazing!  And familiar to us all.  MS uses them already for the toolbar buttons, but it could use them a LOT MORE?  Tooltips be added to every setting in the preferences dialogs (which is a common place for them) defining the setting and suggesting values.
Could they also be added for all the menu items?  Not just the toolbar buttons?  Not that common, but still very, very desirable.
The tool tips should be an explanation of the feature, and if possible, with perhaps a few notes on applications, suggested values, etc.
As tooltips appear after a delay, even a long explanation, or lots of details about it, would not affect the usage, experience by the user, it won't get in the way.  If you pause, you get a good explanation.  If you know what you're doing, they proably don't get enough time to appear.
Flesh these tooltips out, and enable them everywhere!
Example scenarios:  In the manual, it would be great if a lot of the features had examples of where it could be used, and how it would be used for different uses of MS... So there would be examples for aerial/drone work, examples for turntable rigs, for interiors, etc, etc. where the settings might be different for the different uses.
Crowd-sourced explanations and examples:  Perhaps the users that have gained a lot of experience with MS could submit their settings and insight about various features, say as concise case studies.
It could even be that each time Alexey fleshes out an explanation of a feature for us, after a forum user posts, then we could take that explanation and submit it in a 'Tooltip' format and a revised Manual entry.  The documentation would then grow as a when features are asked about and explained.
Workflows:  One of the most useful, educational, and even reassuring documents, is the USGS Processing Workflow.  Probably one of the most valuable resources to a lot of us.  It tells us what, when and why, to get the outputs they needed.
If we could get a collection of these, submitted by us users, for all of our different use cases, then that would be absolutely amazing, so useful.
Each workflow could then be critiqued by us peers and the devs, and then perhaps updated as we learn new things, new features come along.  The author optimises their workflow, we all learn from their workflow.
Having a few different workflows for your type of use case would be great.  Some for drone surveys, some for underwater surveys, some for scanning archaeological sites, or museum specimens on turntables, scanning cars, etc, etc, etc...
This would allow any new user to get up to a reasonable speed, very, very quickly!

Fleshing out good quality documentation, manuals, etc is not easy, it's very time consuming, and needs maintaining... The devs are busy enough coding new features and making MS faster... But it's very, very important...  If it can be improved, it absolutely will help us all...  And the easier to use software will ultimately sell more copies.
Cheese, very important and useful post, fully agree...an effort must be done to better document the software!

Another important point and related to information sharing, is for a better explanation of which bugs have been fixed in each new release change log. IMHO, just stating
Quote
Bug fixes
is not suficient.
Each bug fix must be explained by its number and description... I think it is basic to good software maintenance and development...

But I think little by little things will improve. As for example, lately many informative tutorials have been posted...
« Last Edit: October 17, 2021, 06:27:51 PM by Paulo »
Best Regards,

Paul Pelletier

MightyMM

  • Newbie
  • *
  • Posts: 1
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #7 on: October 18, 2021, 02:29:35 AM »
The new feature appears promising my preliminary testing with a Erosion radius of 0.05 does a good job of removing the sides of buildings and "tree stumps" however because the algorithm removes the ground classification from a radius around all points outside of the estimated ground surface (regardless of the proximity to the ground) there is issues with the canopy of trees declassifying areas of ground underneath.

This could be improved by only using points say .5m above the limit of the estimated surface classification in the erosion radius feature rather than all the points.

Costas

  • Newbie
  • *
  • Posts: 44
  • Aerial Mapping
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #8 on: October 20, 2021, 10:18:19 AM »
For the classification, I still prefer the approach where the terrain is evaluated "from below".

Hello c-r-o-n-o-s.

When you say "from below" you refer in Cloud Compare and the CSF (Cloth Simulation Filter) plugin?

dpitman

  • Full Member
  • ***
  • Posts: 154
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #9 on: October 31, 2021, 07:49:27 AM »
For the classification, I still prefer the approach where the terrain is evaluated "from below".

Hello c-r-o-n-o-s.

When you say "from below" you refer in Cloud Compare and the CSF (Cloth Simulation Filter) plugin?

I think so, yes.  I brought that up recently and didn't get much reaction.

https://www.agisoft.com/forum/index.php?topic=13700.0

jetdog6

  • Newbie
  • *
  • Posts: 10
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #10 on: November 15, 2021, 10:19:09 PM »
Anyone notice that if the erosion radius is used (putting in a non 0 number), that the classify from setting is ignored?  It will classify the whole project.

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 13222
    • View Profile
Re: Added Erosion radius option to Classify Ground Points dialog
« Reply #11 on: November 16, 2021, 12:19:30 PM »
Hello jetdog6,

After a few tries I am not able to reproduce that, can you provide the screenshots of source dense cloud classification, parameters used in the Classify Ground Points dialog and the results of classification?
Best regards,
Alexey Pasumansky,
Agisoft LLC