https://github.com/dymaxionlabs/massive-change-detection
QGIS 2 plugin for applying change detection algorithms on high resolution satellite imagery
https://github.com/dymaxionlabs/massive-change-detection
change-detection qgis-plugin qgis-processing-provider remote-sensing
Last synced: about 1 month ago
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QGIS 2 plugin for applying change detection algorithms on high resolution satellite imagery
- Host: GitHub
- URL: https://github.com/dymaxionlabs/massive-change-detection
- Owner: dymaxionlabs
- License: gpl-3.0
- Created: 2018-07-19T13:50:59.000Z (almost 7 years ago)
- Default Branch: master
- Last Pushed: 2018-07-28T15:43:08.000Z (almost 7 years ago)
- Last Synced: 2024-04-24T12:14:09.417Z (about 1 year ago)
- Topics: change-detection, qgis-plugin, qgis-processing-provider, remote-sensing
- Language: Python
- Size: 667 KB
- Stars: 23
- Watchers: 5
- Forks: 7
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- Contributing: CONTRIBUTING.md
- License: LICENSE.md
- Code of conduct: CODE_OF_CONDUCT.md
Awesome Lists containing this project
README
# Massive Change Detection - QGIS plugin
[](https://travis-ci.org/dymaxionlabs/massive-change-detection)
[](https://gitter.im/dymaxionlabs/massive-change-detection?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
QGIS 2 plugin that applies change detection algorithms on satellite imagery for
building reports for urban planning.
## Install
### Add plugins repository
To install this plugin, you need to add our QGIS Repository first. Go to
`Plugins -> Manage and Install Plugins`.
On the Settings tab, enable `Show also experimental plugins`, and add a
repository named `Dymaxion Labs` with the following URL:
```
https://dymaxionlabs.github.io/qgis-repository/plugins.xml
```
After that, press `Reload all repositories` button to load our plugins index
into QGIS.
### Install external dependencies
This plugin makes use of some additional Python dependencies. In a terminal,
run the following:
```
pip install --user fiona numpy opencv-python rasterio shapely
```
### Install plugin
Finally, go to `Plugins -> Manage and Install Plugins`, and in `All` or `Not
Installed` tabs, search for *Massive Change Detection*. Click `Install
plugin`.
## Usage
This is a *processing plugin*, you will have to enable the Processing Toolbox
on QGIS to use it properly.
### Step 1: Generate change detection raster
The first step is to generate a *change detection raster* based on two raster
images. The algorithm detects changes between the *"old"/"before" image* and
the *"new"/"after" image* and generates a new binary raster of changes.
Both input rasters must be coregistered and be of the same size and resolution.
If you have images of different size and/or resolution, you will need to
manually superimpose and clip them first. You can use [Orfeo
Toolbox](https://www.orfeo-toolbox.org/start/) to do this (see Superimpose).
Suppose you have two raster layers loaded on QGIS: `before.tif` and
`after.tif`. Select `Massive Change Detection -> Pixel-based algorithms ->
Multiband Difference` from the Processing Toolbox.
Use `before.tif` layer on `Input old layer` and `after.tif` layer on `Input new
layer`. You can use automatic thresholding (Otsu's method) or manually set a
threshold by unchecking `Automatic thresholding` and choosing a proper value on
`Threshold value`. You can adjust the post-processing filter and its kernel
size for better results. Finally click `Run` to process the image.
### Step 2: Build report of changes
The second step is to build a changed lots report based on a vector layer of
lots and a change detection raster. Lots vector layer must be in the same
projection as rasters.
Select `Massive Change Detection -> Report -> Generate changed lots data` from
the Processing Toolbox.
Use your change detection raster (already generated on Step 1) on `Input change
detection layer`, select one of your input raster images (`before.tif`, or
`after.tif`) on `Input image layer`. Then set your lots vector layer on `Input
lots vector layer` field, and select the lot id field on `Lot id field`.
The selection threshold is related to the percentage of detected change in a
particular lot. For example, 0.5 means that a lot that has changed more than
50% of its area is marked as *changed*.
This algorithm will generate both a new vector layer of changed lots and a
table (CSV) layer.
## Development
Clone the repository inside your QGIS plugin directory. On Ubuntu this would
be `~/.qgis2/python/plugins/`:
```
cd ~/.qgis2/python/plugins/
git clone https://github.com/dymaxionlabs/massive-change-detection
cd massive-change-detection
```
Install packages for test and code coverage.
```
pip install --user -r requirements.txt
```
If you have installed QGIS from source use `scripts/run-env-linux.sh` to set up
the environment variables so that Python can find QGIS inside your virtual
environment. For example, if it is `/opt/qgis2`:
```
source scripts/run-env-linux.sh /opt/qgis2
```
Run tests and build code coverage reports with `make test`.
### I18n
You can find the list of supported locales is in the `LOCALES` definition on
`Makefile`. If you want to add a new language, you have to add it there first.
Prepare translations strings with `make transup`. This command will search all
translated strings in the repository and generate `.ts` files.
Edit the translations files (files ending in `.ts`) in `i18n/`.
Finally compile translation strings with `make transcompile`.
## Issue tracker
Please report any bugs and enhancement ideas using the GitHub issue tracker:
https://github.com/dymaxionlabs/massive-change-detection/issues
Feel free to also ask questions on our [Gitter
channel](https://gitter.im/dymaxionlabs/massive-change-detection), or by email.
## Help wanted
Any help in testing, development, documentation and other tasks is highly
appreciated and useful to the project.
For more details, see the file [CONTRIBUTING.md](CONTRIBUTING.md).
## License
Source code is released under a GNU GPL v3 license. Please refer to
[LICENSE.md](LICENSE.md) for more information.