Pico’s Pictures: DarkTable Anonymization
Hello, friends! I went on an exploration of some features of DarkTable 4.4 and I would like to share them with you.
Question: How does one use DarkTable’s ability to add location and tags into the EXIF data, but anonymize the data when sharing it with an unknown audience?
When sharing with an unknown audience, I want to protect people and places from the worst of the internet and add Creative Commons copyright so that it can be shared and edited with attribution non-commercially.
The procedure wasn’t too bad, once I found where all the bodies were hidden. The following describes the workflow that meets my needs and involved setting up three modules: watermark, metadata editor, and export.
1. Multiple presets were created in the ‘watermark’ module which allows me to apply a watermark on the image in multiple locations with different personas. I saved them as a style so that I can bulk apply them as a closing post-processing step.
2. Created two presets in the ‘metadata editor’ module, one with a ‘Creative Commons’ and my public pseudonym and another for my personal photos.
3. Created two presets in the ‘export’, one that exports all EXIF, tags, and metadata and writes to my personal network storage at full size. The second preset adds the copyright and pseudonym, removes ‘tag’ data, removes location data from EXIF data. The ‘anonymize’ preset also creates generic file names and writes to a separate folder intended for sharing on the internet and scales the image to 1/4 of the original size and uses web safe colors.
https://jimpl.com/ was used to view the EXIF data in the browser to make sure my exports were behaving as expected. The image in this post was verified with it if you’d like to try and download it and upload it to test it out. I also learned that if you want to continue doing editing in a tool like GIMP, it is best to export as a TIFF format as JPEG compresses and throws away data that cannot be seen. However, this requires that you have done all the anonymization before you hand the file to GIMP for more editing.
