For a while now, I have looked for a sensible way to share images with my family using a self hosted solution, as it is unacceptable to place images from my personal life under the control of strangers working for data hoarders like Google or Dropbox. The last few days I have drafted an approach that might work out, and I would like to share it with you. I would like to publish images on a server under my control, and point some Internet connected display units using some free and open standard to the images I published. As my primary language is not limited to ASCII, I need to store metadata using UTF-8. Many years ago, I hoped to find a digital photo frame capable of reading a RSS feed with image references (aka using the <enclosure> RSS tag), but was unable to find a current supplier of such frames. In the end I gave up that approach.
Some months ago, I discovered that XScreensaver is able to read images from a RSS feed, and used it to set up a screen saver on my home info screen, showing images from the Daily images feed from NASA. This proved to work well. More recently I discovered that Kodi (both using OpenELEC and LibreELEC) provide the Feedreader screen saver capable of reading a RSS feed with images and news. For fun, I used it this summer to test Kodi on my parents TV by hooking up a Raspberry PI unit with LibreELEC, and wanted to provide them with a screen saver showing selected pictures from my selection.
Armed with motivation and a test photo frame, I set out to generate a RSS feed for the Kodi instance. I adjusted my Freedombox instance, created /var/www/html/privatepictures/, wrote a small Perl script to extract title and description metadata from the photo files and generate the RSS file. I ended up using Perl instead of python, as the libimage-exiftool-perl Debian package seemed to handle the EXIF/XMP tags I ended up using, while python3-exif did not. The relevant EXIF tags only support ASCII, so I had to find better alternatives. XMP seem to have the support I need.
I am a bit unsure which EXIF/XMP tags to use, as I would like to use tags that can be easily added/updated using normal free software photo managing software. I ended up using the tags set using this exiftool command, as these tags can also be set using digiKam:
exiftool -headline='The RSS image title' \ -description='The RSS image description.' \ -subject+=for-family photo.jpeg
I initially tried the "-title" and "keyword" tags, but they were invisible in digiKam, so I changed to "-headline" and "-subject". I use the keyword/subject 'for-family' to flag that the photo should be shared with my family. Images with this keyword set are located and copied into my Freedombox for the RSS generating script to find.
Are there better ways to do this? Get in touch if you have better suggestions.
As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address 15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b.