+ <div class="entry">
+ <div class="title"><a href="http://people.skolelinux.org/pere/blog/Software_created_using_taxpayers__money_should_be_Free_Software.html">Software created using taxpayers’ money should be Free Software</a></div>
+ <div class="date">30th August 2018</div>
+ <div class="body"><p>It might seem obvious that software created using tax money should
+be available for everyone to use and improve. Free Software
+Foundation Europe recentlystarted a campaign to help get more people
+to understand this, and I just signed the petition on
+<a href="https://publiccode.eu/">Public Money, Public Code</a> to help
+them. I hope you too will do the same.</p>
+</div>
+ <div class="tags">
+
+
+ Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett</a>.
+
+
+ </div>
+ </div>
+ <div class="padding"></div>
+
+ <div class="entry">
+ <div class="title"><a href="http://people.skolelinux.org/pere/blog/A_bit_more_on_privacy_respecting_health_monitor___fitness_tracker.html">A bit more on privacy respecting health monitor / fitness tracker</a></div>
+ <div class="date">13th August 2018</div>
+ <div class="body"><p>A few days ago, I wondered if there are any privacy respecting
+health monitors and/or fitness trackers available for sale these days.
+I would like to buy one, but do not want to share my personal data
+with strangers, nor be forced to have a mobile phone to get data out
+of the unit. I've received some ideas, and would like to share them
+with you.
+
+One interesting data point was a pointer to a Free Software app for
+Android named
+<a href="https://github.com/Freeyourgadget/Gadgetbridge/">Gadgetbridge</a>.
+It provide cloudless collection and storing of data from a variety of
+trackers. Its
+<a href="https://github.com/Freeyourgadget/Gadgetbridge/#supported-devices">list
+of supported devices</a> is a good indicator for units where the
+protocol is fairly open, as it is obviously being handled by Free
+Software. Other units are reportedly encrypting the collected
+information with their own public key, making sure only the vendor
+cloud service is able to extract data from the unit. The people
+contacting me about Gadgetbirde said they were using
+<a href="https://us.amazfit.com/shop/bip?variant=336750">Amazfit
+Bip</a> and
+<a href="http://www.xiaomimi6phone.com/xiaomi-mi-band-3-features-release-date-rumors/">Xiaomi
+Band 3</a>.</p>
+
+<p>I also got a suggestion to look at some of the units from Garmin.
+I was told their GPS watches can be connected via USB and show up as a
+USB storage device with
+<a href="https://www.gpsbabel.org/htmldoc-development/fmt_garmin_fit.html">Garmin
+FIT files</a> containing the collected measurements. While
+proprietary, FIT files apparently can be read at least by
+<a href="https://www.gpsbabel.org">GPSBabel</a> and the
+<a href="https://apps.nextcloud.com/apps/gpxpod">GpxPod</a> Nextcloud
+app. It is unclear to me if they can read step count and heart rate
+data. The person I talked to was using a
+<a href="https://buy.garmin.com/en-US/US/p/564291">Garmin Forerunner
+935</a>, which is a fairly expensive unit. I doubt it is worth it for
+a unit where the vendor clearly is trying its best to move from open
+to closed systems. I still remember when Garmin dropped NMEA support
+in its GPSes.</p>
+
+<p>A final idea was to build ones own unit, perhaps by basing it on a
+wearable hardware platforms like
+<a href="https://learn.adafruit.com/flora-geo-watch">the Flora Geo
+Watch</a>. Sound like fun, but I had more money than time to spend on
+the topic, so I suspect it will have to wait for another time.</p>
+
+<p>While I was working on tracking down links, I came across an
+inspiring TED talk by Dave Debronkart about
+<a href="https://archive.org/details/DavedeBronkart_2010X">being a
+e-patient</a>, and discovered the web site
+<a href="https://participatorymedicine.org/epatients/">Participatory
+Medicine</a>. If you too want to track your own health and fitness
+without having information about your private life floating around on
+computers owned by others, I recommend checking it out.</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>
+</div>
+ <div class="tags">
+
+
+ Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
+
+
+ </div>
+ </div>
+ <div class="padding"></div>
+
+ <div class="entry">
+ <div class="title"><a href="http://people.skolelinux.org/pere/blog/Privacy_respecting_health_monitor___fitness_tracker_.html">Privacy respecting health monitor / fitness tracker?</a></div>
+ <div class="date"> 7th August 2018</div>
+ <div class="body"><p>Dear lazyweb,</p>
+
+<p>I wonder, is there a fitness tracker / health monitor available for
+sale today that respect the users privacy? With this I mean a
+watch/bracelet capable of measuring pulse rate and other
+fitness/health related values (and by all means, also the correct time
+and location if possible), which is <strong>only</strong> provided for
+me to extract/read from the unit with computer without a radio beacon
+and Internet connection. In other words, it do not depend on a cell
+phone app, and do make the measurements available via other peoples
+computer (aka "the cloud"). The collected data should be available
+using only free software. I'm not interested in depending on some
+non-free software that will leave me high and dry some time in the
+future. I've been unable to find any such unit. I would like to buy
+it. The ones I have seen for sale here in Norway are proud to report
+that they share my health data with strangers (aka "cloud enabled").
+Is there an alternative? I'm not interested in giving money to people
+requiring me to accept "privacy terms" to allow myself to measure my
+own health.</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>
+</div>
+ <div class="tags">
+
+
+ Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
+
+
+ </div>
+ </div>
+ <div class="padding"></div>
+
+ <div class="entry">
+ <div class="title"><a href="http://people.skolelinux.org/pere/blog/Sharing_images_with_friends_and_family_using_RSS_and_EXIF_XMP_metadata.html">Sharing images with friends and family using RSS and EXIF/XMP metadata</a></div>
+ <div class="date">31st July 2018</div>
+ <div class="body"><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. 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.</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. The relevant EXIF
+tags only support ASCII, so I had to find better alternatives. XMP
+seem to have the support I need.</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>
+</div>
+ <div class="tags">
+
+
+ Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
+
+
+ </div>
+ </div>
+ <div class="padding"></div>
+
+ <div class="entry">
+ <div class="title"><a href="http://people.skolelinux.org/pere/blog/Simple_streaming_the_Linux_desktop_to_Kodi_using_GStreamer_and_RTP.html">Simple streaming the Linux desktop to Kodi using GStreamer and RTP</a></div>
+ <div class="date">12th July 2018</div>
+ <div class="body"><p>Last night, I wrote
+<a href="http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html">a
+recipe to stream a Linux desktop using VLC to a instance of Kodi</a>.
+During the day I received valuable feedback, and thanks to the
+suggestions I have been able to rewrite the recipe into a much simpler
+approach requiring no setup at all. It is a single script that take
+care of it all.</p>
+
+<p>This new script uses GStreamer instead of VLC to capture the
+desktop and stream it to Kodi. This fixed the video quality issue I
+saw initially. It further removes the need to add a m3u file on the
+Kodi machine, as it instead connects to
+<a href="https://kodi.wiki/view/JSON-RPC_API/v8">the JSON-RPC API in
+Kodi</a> and simply ask Kodi to play from the stream created using
+GStreamer. Streaming the desktop to Kodi now become trivial. Copy
+the script below, run it with the DNS name or IP address of the kodi
+server to stream to as the only argument, and watch your screen show
+up on the Kodi screen. Note, it depend on multicast on the local
+network, so if you need to stream outside the local network, the
+script must be modified. Also note, I have no idea if audio work, as
+I only care about the picture part.</p>
+
+<blockquote><pre>
+#!/bin/sh
+#
+# Stream the Linux desktop view to Kodi. See
+# http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html
+# for backgorund information.
+
+# Make sure the stream is stopped in Kodi and the gstreamer process is
+# killed if something go wrong (for example if curl is unable to find the
+# kodi server). Do the same when interrupting this script.
+kodicmd() {
+ host="$1"
+ cmd="$2"
+ params="$3"
+ curl --silent --header 'Content-Type: application/json' \
+ --data-binary "{ \"id\": 1, \"jsonrpc\": \"2.0\", \"method\": \"$cmd\", \"params\": $params }" \
+ "http://$host/jsonrpc"
+}
+cleanup() {
+ if [ -n "$kodihost" ] ; then
+ # Stop the playing when we end
+ playerid=$(kodicmd "$kodihost" Player.GetActivePlayers "{}" |
+ jq .result[].playerid)
+ kodicmd "$kodihost" Player.Stop "{ \"playerid\" : $playerid }" > /dev/null
+ fi
+ if [ "$gstpid" ] && kill -0 "$gstpid" >/dev/null 2>&1; then
+ kill "$gstpid"
+ fi
+}
+trap cleanup EXIT INT
+
+if [ -n "$1" ]; then
+ kodihost=$1
+ shift
+else
+ kodihost=kodi.local
+fi
+
+mcast=239.255.0.1
+mcastport=1234
+mcastttl=1
+
+pasrc=$(pactl list | grep -A2 'Source #' | grep 'Name: .*\.monitor$' | \
+ cut -d" " -f2|head -1)
+gst-launch-1.0 ximagesrc use-damage=0 ! video/x-raw,framerate=30/1 ! \
+ videoconvert ! queue2 ! \
+ x264enc bitrate=8000 speed-preset=superfast tune=zerolatency qp-min=30 \
+ key-int-max=15 bframes=2 ! video/x-h264,profile=high ! queue2 ! \
+ mpegtsmux alignment=7 name=mux ! rndbuffersize max=1316 min=1316 ! \
+ udpsink host=$mcast port=$mcastport ttl-mc=$mcastttl auto-multicast=1 sync=0 \
+ pulsesrc device=$pasrc ! audioconvert ! queue2 ! avenc_aac ! queue2 ! mux. \
+ > /dev/null 2>&1 &
+gstpid=$!
+
+# Give stream a second to get going
+sleep 1
+
+# Ask kodi to start streaming using its JSON-RPC API
+kodicmd "$kodihost" Player.Open \
+ "{\"item\": { \"file\": \"udp://@$mcast:$mcastport\" } }" > /dev/null
+
+# wait for gst to end
+wait "$gstpid"
+</pre></blockquote>
+
+<p>I hope you find the approach useful. I know I do.</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>
+</div>
+ <div class="tags">
+
+
+ Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/video">video</a>.
+
+
+ </div>
+ </div>
+ <div class="padding"></div>
+
projects / homepage.git / blobdiff