diff --git a/source/map-accuracy.rst b/source/map-accuracy.rst index 7ed568340..7d28da764 100644 --- a/source/map-accuracy.rst +++ b/source/map-accuracy.rst @@ -269,6 +269,110 @@ When previously mapped sites need revisited, OpenDroneMap can align multiple ver Animated gif comparing two separately processed, but aligned digital surface models. +Plugin Time-SIFT +================ + +This script does Time-SIFT processing with ODM. Time-SIFT is a method +for multi-temporal analysis without the need to co-registrate the data. + + D. Feurer, F. Vinatier, Joining multi-epoch archival aerial images in + a single SfM block allows 3-D change detection with almost + exclusively image information, ISPRS Journal of Photogrammetry and + Remote Sensing, Volume 146, 2018, Pages 495-506, ISSN 0924-2716, doi: + 10.1016/j.isprsjprs.2018.10.016 + (https://doi.org/10.1016/j.isprsjprs.2018.10.016) + +Requirements +------------ + +- ODM ! :-) +- subprocess +- json +- os +- shutil +- pathlib +- sys +- argparse +- textwrap + +Usage +----- + +Provided example +~~~~~~~~~~~~~~~~ + +Download or clone `this +repo `__ +to get example data. + +Then execute + +:: + + python Timesift_odm.py datasets --end-with odm_filterpoints + +It should make the Time-SIFT processing on the downloaded example data, +stopping after the filtered dense clouds step. + +In the destination dir, you should obtain new directories, ``0_before`` +and ``1_after`` at the same level as the ``time-sift-block`` directory. +These new directories contain all the results natively co-registered. + +You can then use `CloudCompare `__ to compute +distance between the +``datasets/0_before/odm_filterpoints/point_cloud.ply`` and the +``datasets/1_after/odm_filterpoints/point_cloud.ply`` and obtain this +image showing the difference between the two 3D surfaces. Here, two soil +samples were excavated as can be seen on the image below. |image1| + +Your own data +~~~~~~~~~~~~~ + +In your dataset directory (usually ``datasets``, but you can have chosen +another name) you have to prepare a Time-SIFT project directory (default +name : ``time-sift-block``, *can be tuned via a parameter*) that +contains : \* ``images/`` : a subdirectory with all images of all +epochs. This directory name is fixed as it is the one expected by ODM \* +``images_epochs.txt`` : a file that has the same format as the file used +for the split and merge ODM function. This file name *can be tuned via a +parameter*. + +The ``images_epochs.txt`` file has two columns, the first column +contains image names and the second contains the epoch name as follows + +:: + + DSC_0368.JPG 0_before + DSC_0369.JPG 0_before + DSC_0370.JPG 0_before + DSC_0389.JPG 1_after + DSC_0390.JPG 1_after + DSC_0391.JPG 1_after + +Your directory, before running the script, should look like this : + +:: + + $PWD/datasets/ + └── time-sift-block/ + ├── images/ + └── images_epochs.txt + +At the end of the script you obtain a directory by epoch (at the same +level as the Time-SIFT project directory). Each directory is processed +with images of each epoch and all results are natively co-registered due +to the initial sfm step done with all images. + +:: + + $PWD/datasets/ + ├── 0_before/ + ├── 1_after/ + └── time-sift-block/ + +.. |image1| image:: https://forge.inrae.fr/Denis.Feurer/timesift-odm-data-example/-/raw/main/Example.png?ref_type=heads + + ----------------------- Aligning Large Datasets -----------------------