Vjylku

Empty optional argument or Not giving optional argument at all?

What is formjacking?

How should I ship cards?

Why is quixotic not Quixotic (a proper adjective)?

Is it possible to detect 100% of SQLi with a simple regex?

Microphone on Mars

Can a planet be tidally unlocked?

How do I know my password or backup information is not being shared when creating a new wallet?

Isn't a semicolon (';') needed after a function declaration in C++?

How can changes in personality/values of a person who turned into a vampire be explained?

Found a major flaw in paper from home university – to which I would like to return

Exploding Numbers

How to write painful torture scenes without being over-the-top

Build ASCII Podiums

Boss asked me to sign a resignation paper without a date on it along with my new contract

How can a kingdom keep the secret of a missing monarch from the public?

The Longest Chess Game

How do I handle a blinded enemy which wants to attack someone it's sure is there?

Last Reboot commands don't agree

What did Putin say about a US deep state in his state-of-the-nation speech; what has he said in the past?

Manager has noticed coworker's excessive breaks. Should I warn him?

80-bit collision resistence because of 80-bit x87 registers?

Why Third 'Reich'? Why is 'reich' not translated when 'third' is? What is the English synonym of reich?

Which was the first story to feature space elevators?

Point cloud/image comparison?

Processing MOD35 cloud mask image?3d model to point cloudGeoReference XYZ point cloudThinning large LiDAR point cloud?Resampling point cloud data using ArcGIS Desktop?Reduce point cloud elevation dataSeeking open source point cloud software?Import point cloud (.ply) into PostgreSQL ( PostGIS )Georeferencing terrestrial LiDAR point cloud?Vertical 3D Point Cloud visualisation

-1

I used MATLAB software to classify point cloud data into 3 classes; (1) main; (2) protrusion and (3) recess. In MATLAB I assigned a distinctive color to each class to differentiate between classes (yellow, red and blue; but black is not among classification color and it is only background color which is the places which no point exist and therefore, no class was assigned). When the classified point cloud displayed, I took a screen shot of it (TIFF images attached). I wish if I could attach point clouds (txt format), but apparently it is not possible.

In my MATLAB code, there are several parameters to adjust to get the optimum classification results (presented in three colors in reference image and reference point cloud). If I change those parameters from optimum values to other values, then the classification results are changed.

Now, if I assume the reference figure (or reference point cloud) is the base for comparison, I need to calculate how much accurate the other three figures have been classified?

For example, if I say %30 of whole reference image is in red (openings), then how much is this red percentage in any of the other three figures?

Similarly for blue and yellow color percentage. This percentage or any other quantitative comparison. I have been trying to find out a way to compare the accuracy of classification either using MATLAB or ARC GIS/MAPS, ENVI or any other tools, but so far no luck.

image point-cloud

share|improve this question

edited 4 hours ago

PolyGeo♦

53.5k1780240

asked yesterday

fifififi

1

New contributor

fifi is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

add a comment | 

-1

I used MATLAB software to classify point cloud data into 3 classes; (1) main; (2) protrusion and (3) recess. In MATLAB I assigned a distinctive color to each class to differentiate between classes (yellow, red and blue; but black is not among classification color and it is only background color which is the places which no point exist and therefore, no class was assigned). When the classified point cloud displayed, I took a screen shot of it (TIFF images attached). I wish if I could attach point clouds (txt format), but apparently it is not possible.

In my MATLAB code, there are several parameters to adjust to get the optimum classification results (presented in three colors in reference image and reference point cloud). If I change those parameters from optimum values to other values, then the classification results are changed.

Now, if I assume the reference figure (or reference point cloud) is the base for comparison, I need to calculate how much accurate the other three figures have been classified?

For example, if I say %30 of whole reference image is in red (openings), then how much is this red percentage in any of the other three figures?

Similarly for blue and yellow color percentage. This percentage or any other quantitative comparison. I have been trying to find out a way to compare the accuracy of classification either using MATLAB or ARC GIS/MAPS, ENVI or any other tools, but so far no luck.

image point-cloud

share|improve this question

edited 4 hours ago

PolyGeo♦

53.5k1780240

asked yesterday

fifififi

1

New contributor

fifi is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

add a comment | 

I used MATLAB software to classify point cloud data into 3 classes; (1) main; (2) protrusion and (3) recess. In MATLAB I assigned a distinctive color to each class to differentiate between classes (yellow, red and blue; but black is not among classification color and it is only background color which is the places which no point exist and therefore, no class was assigned). When the classified point cloud displayed, I took a screen shot of it (TIFF images attached). I wish if I could attach point clouds (txt format), but apparently it is not possible.

In my MATLAB code, there are several parameters to adjust to get the optimum classification results (presented in three colors in reference image and reference point cloud). If I change those parameters from optimum values to other values, then the classification results are changed.

Now, if I assume the reference figure (or reference point cloud) is the base for comparison, I need to calculate how much accurate the other three figures have been classified?

For example, if I say %30 of whole reference image is in red (openings), then how much is this red percentage in any of the other three figures?

Similarly for blue and yellow color percentage. This percentage or any other quantitative comparison. I have been trying to find out a way to compare the accuracy of classification either using MATLAB or ARC GIS/MAPS, ENVI or any other tools, but so far no luck.

image point-cloud

share|improve this question

edited 4 hours ago

PolyGeo♦

53.5k1780240

asked yesterday

fifififi

1

New contributor

fifi is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

share|improve this question

edited 4 hours ago

PolyGeo♦

53.5k1780240

asked yesterday

fifififi

1

New contributor

fifi is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

share|improve this question

edited 4 hours ago

PolyGeo♦

53.5k1780240

asked yesterday

fifififi

1

New contributor

fifi is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

edited 4 hours ago

PolyGeo♦

53.5k1780240

edited 4 hours ago

PolyGeo♦

53.5k1780240

asked yesterday

fifififi

1

New contributor

fifi is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked yesterday

fifififi

1

1 Answer
1

active

oldest

votes

0

If I undestood correctly, what you are looking for is called an "accuracy assessment". This can be done in most GIS Software, most of the time it's to calculate the accuracy of raster classifications.

The output of an accuracy assessment is a "confusion matrix", which basically tells you, how accurate the classification of each class was. So if you got 2 classes red and yellow, it tells you how many "red" where correctly classified as "red", how many "yellow" where falsely classified as "red", and how many "red" where falsely classified as "yellow" (and so on).

Here is the implementation in ArcGIS and more information about the confusion matrix, it basically works the same in every GIS that can handle raster data.

share|improve this answer

answered yesterday

RobRob

463

New contributor

Rob is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

add a comment | 

Your Answer

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "79"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});

fifi is a new contributor. Be nice, and check out our Code of Conduct.

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fgis.stackexchange.com%2fquestions%2f312903%2fpoint-cloud-image-comparison%23new-answer', 'question_page');
}
);

Post as a guest

Name

Email

Required, but never shown

0

If I undestood correctly, what you are looking for is called an "accuracy assessment". This can be done in most GIS Software, most of the time it's to calculate the accuracy of raster classifications.

The output of an accuracy assessment is a "confusion matrix", which basically tells you, how accurate the classification of each class was. So if you got 2 classes red and yellow, it tells you how many "red" where correctly classified as "red", how many "yellow" where falsely classified as "red", and how many "red" where falsely classified as "yellow" (and so on).

Here is the implementation in ArcGIS and more information about the confusion matrix, it basically works the same in every GIS that can handle raster data.

share|improve this answer

answered yesterday

RobRob

463

New contributor

Rob is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

add a comment | 

0

If I undestood correctly, what you are looking for is called an "accuracy assessment". This can be done in most GIS Software, most of the time it's to calculate the accuracy of raster classifications.

The output of an accuracy assessment is a "confusion matrix", which basically tells you, how accurate the classification of each class was. So if you got 2 classes red and yellow, it tells you how many "red" where correctly classified as "red", how many "yellow" where falsely classified as "red", and how many "red" where falsely classified as "yellow" (and so on).

Here is the implementation in ArcGIS and more information about the confusion matrix, it basically works the same in every GIS that can handle raster data.

share|improve this answer

answered yesterday

RobRob

463

New contributor

Rob is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

add a comment | 

If I undestood correctly, what you are looking for is called an "accuracy assessment". This can be done in most GIS Software, most of the time it's to calculate the accuracy of raster classifications.

The output of an accuracy assessment is a "confusion matrix", which basically tells you, how accurate the classification of each class was. So if you got 2 classes red and yellow, it tells you how many "red" where correctly classified as "red", how many "yellow" where falsely classified as "red", and how many "red" where falsely classified as "yellow" (and so on).

Here is the implementation in ArcGIS and more information about the confusion matrix, it basically works the same in every GIS that can handle raster data.

share|improve this answer

answered yesterday

RobRob

463

New contributor

Rob is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

share|improve this answer

answered yesterday

RobRob

463

New contributor

Rob is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

answered yesterday

RobRob

463

New contributor

Rob is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

answered yesterday

RobRob

463