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+Title: Sharing images with friends and family using RSS and EXIF/XMP metadata
+Tags: english, debian
+Date: 2018-07-31 23:30
+
+<p>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.  Many years ago, I
+hoped to find a digital photo frame capable of reading a RSS feed with
+image references (aka using the &lt;enclosure&gt; RSS tag), but was
+unable to find a sensible supplier of such frames.  In the end I gave
+up that approach.</p>
+
+<p>Some months ago, I discovered that
+<a href="https://www.jwz.org/xscreensaver/">XScreensaver</a> 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
+<a href="https://kodi.tv">Kodi</a> (both using
+<a href="https://www.openelec.tv/">OpenELEC</a> and
+<a href="https://libreelec.tv">LibreELEC</a>) provide the
+<a href="https://github.com/grinsted/script.screensaver.feedreader">Feedreader</a>
+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.</p>
+
+<p>Armed with motivation and a test photo frame, I set out to generate
+a RSS feed for the Kodi instance.  I adjusted my
+<a href="https://freedombox.org/">Freedombox</a> 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.</p>
+
+<p>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:</p>
+
+<blockquote><pre>
+exiftool -headline='The RSS image title' \
+  -description='The RSS image description.' \
+  -subject+=for-family photo.jpeg
+</pre></blockquote>
+
+<p>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.</p>
+
+<p>Are there better ways to do this?  Get in touch if you have better
+suggestions.</p>
+
+<p>As usual, if you use Bitcoin and want to show your support of my
+activities, please send Bitcoin donations to my address
+<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>