X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/35bcc4f0426043d390b78cd27c2f0959ad39c3ca..2aafae50dc90da8ae2432aaeca9569fbe49cf7d7:/blog/index.rss diff --git a/blog/index.rss b/blog/index.rss index 8c9945defa..0581cf3d48 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -7,204 +7,179 @@ - Self-appointed leaders of the Free World - http://people.skolelinux.org/pere/blog/Self_appointed_leaders_of_the_Free_World.html - http://people.skolelinux.org/pere/blog/Self_appointed_leaders_of_the_Free_World.html - Thu, 22 Mar 2018 11:00:00 +0100 - <p>The leaders of the worlds have started to congratulate the -re-elected Russian head of state, and this causes some criticism. I -am though a little fascinated by a comment from USA senator John McCain, -<a href="http://thehill.com/homenews/senate/379339-mccain-rips-trumps-congratulatory-call-to-putin-as-insult-to-russian-people">sited -by The Hill and others</a>: - -<p><blockquote> -<p>"An American president does not lead the Free World by -congratulating dictators on winning sham elections."</p> -</blockquote></p> - -<p>While I totally agree with the senator here, the way the quote is -phrased make me suspect that he is unaware of the simple fact that USA -have not lead the Free World since at least before its government -<a href="https://en.wikipedia.org/wiki/Maher_Arar">kidnapped a -completely innocent Canadian citizen in transit on his way home to -Canada via John F. Kennedy International Airport in September 2002 and -sent him to be tortured in Syria for a year</a>.</p> - -<p>USA might be running ahead, but the path they are taking is not the -one taken by any Free World.</p> + Software created using taxpayers’ money should be Free Software + http://people.skolelinux.org/pere/blog/Software_created_using_taxpayers__money_should_be_Free_Software.html + http://people.skolelinux.org/pere/blog/Software_created_using_taxpayers__money_should_be_Free_Software.html + Thu, 30 Aug 2018 13:50:00 +0200 + <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> - Facebooks ability to sell your personal information is the real Cambridge Analytica scandal - http://people.skolelinux.org/pere/blog/Facebooks_ability_to_sell_your_personal_information_is_the_real_Cambridge_Analytica_scandal.html - http://people.skolelinux.org/pere/blog/Facebooks_ability_to_sell_your_personal_information_is_the_real_Cambridge_Analytica_scandal.html - Wed, 21 Mar 2018 16:30:00 +0100 - <p>So, Cambridge Analytica is getting some well deserved criticism for -(mis)using information it got from Facebook about 50 million people, -mostly in the USA. What I find a bit surprising, is how little -criticism Facebook is getting for handing the information over to -Cambridge Analytica and others in the first place. And what about the -people handing their private and personal information to Facebook? -And last, but not least, what about the government offices who are -handing information about the visitors of their web pages to Facebook? -No-one who looked at the terms of use of Facebook should be surprised -that information about peoples interests, political views, personal -lifes and whereabouts would be sold by Facebook.</p> - -<p>What I find to be the real scandal is the fact that Facebook is -selling your personal information, not that one of the buyers used it -in a way Facebook did not approve when exposed. It is well known that -Facebook is selling out their users privacy, but a scandal -nevertheless. Of course the information provided to them by Facebook -would be misused by one of the parties given access to personal -information about the millions of Facebook users. Collected -information will be misused sooner or later. The only way to avoid -such misuse, is to not collect the information in the first place. If -you do not want Facebook to hand out information about yourself for -the use and misuse of its customers, do not give Facebook the -information.</p> - -<p>Personally, I would recommend to completely remove your Facebook -account, and take back some control of your personal information. -<a href="https://www.theguardian.com/technology/2018/mar/19/how-to-protect-your-facebook-privacy-or-delete-yourself-completely">According -to The Guardian</a>, it is a bit hard to find out how to request -account removal (and not just 'disabling'). You need to -<a href="https://www.facebook.com/help/224562897555674?helpref=faq_content">visit -a specific Facebook page</a> and click on 'let us know' on that page -to get to <a href="https://www.facebook.com/help/delete_account">the -real account deletion screen</a>. Perhaps something to consider? I -would not trust the information to really be deleted (who knows, -perhaps NSA, GCHQ and FRA already got a copy), but it might reduce the -exposure a bit.</p> - -<p>If you want to learn more about the capabilities of Cambridge -Analytica, I recommend to see the video recording of the one hour talk -Paul-Olivier Dehaye gave to <a href="">NUUG</a> last april about -<a href="https://www.nuug.no/aktiviteter/20170404-big-data-psychometric/"> -Data collection, psychometric profiling and their impact on -politics</a>.</p> - -<p>And if you want to communicate with your friends and loved ones, -use some end-to-end encrypted method like -<a href="https://www.signal.org/">Signal</a> or -<a href="https://ring.cx/">Ring</a>, and stop sharing your private -messages with strangers like Facebook and Google.</p> + A bit more on privacy respecting health monitor / fitness tracker + http://people.skolelinux.org/pere/blog/A_bit_more_on_privacy_respecting_health_monitor___fitness_tracker.html + http://people.skolelinux.org/pere/blog/A_bit_more_on_privacy_respecting_health_monitor___fitness_tracker.html + Mon, 13 Aug 2018 09:00:00 +0200 + <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> - H, Ap, Frp og Venstre går for DNA-innsamling av hele befolkningen - http://people.skolelinux.org/pere/blog/H__Ap__Frp_og_Venstre_g_r_for_DNA_innsamling_av_hele_befolkningen.html - http://people.skolelinux.org/pere/blog/H__Ap__Frp_og_Venstre_g_r_for_DNA_innsamling_av_hele_befolkningen.html - Wed, 14 Mar 2018 14:15:00 +0100 - <p>I går kom det nok et argument for å holde seg unna det norske -helsevesenet. Da annonserte et stortingsflertall, bestående av Høyre, -Arbeiderpartiet, Fremskrittspartiet og Venstre, at de går inn for å -samle inn og lagre DNA-prøver fra hele befolkningen i Norge til evig -tid. Endringen gjelder innsamlede blodprøver fra nyfødte i Norge. -Det vil dermed ta litt tid før en har hele befolkningen, men det er -dit vi havner gitt nok tid. I dag er det nesten hundre prosent -oppslutning om undersøkelsen som gjøres like etter fødselen, på -bakgrunn av blodprøven det er snakk om å lagre, for å oppdage endel -medfødte sykdommer. Blodprøven lagres i dag i inntil seks år. -<a href="https://www.stortinget.no/no/Saker-og-publikasjoner/Publikasjoner/Innstillinger/Stortinget/2017-2018/inns-201718-182l/?all=true">Stortingets -flertallsinnstilling</a> er at tidsbegrensingen skal fjernes, og mener -at tidsubegrenset lagring ikke vil påvirke oppslutningen om -undersøkelsen.</p> - -<p>Datatilsynet har ikke akkurat applaudert forslaget:</p> - -<p><blockquote> - - <p>«Datatilsynet mener forslaget ikke i tilstrekkelig grad - synliggjør hvilke etiske og personvernmessige utfordringer som må - diskuteres før en etablerer en nasjonal biobank med blodprøver fra - hele befolkningen.»</p> - -</blockquote></p> - -<p>Det er flere historier om hvordan innsamlet biologisk materiale har -blitt brukt til andre formål enn de ble innsamlet til, og historien om -<a href="https://www.aftenposten.no/norge/i/Ql0WR/Na-ma-Folkehelsa-slette-uskyldiges-DNA-info">folkehelseinstituttets -lagring på vegne av politiet (Kripos) av innsamlet biologisk materiale -og DNA-informasjon i strid med loven</a> viser at en ikke kan være -trygg på at lover og intensjoner beskytter de som blir berørt mot -misbruk av slik privat og personlig informasjon.</p> - -<p>Det er verdt å merke seg at det kan forskes på de innsamlede -blodprøvene uten samtykke fra den det gjelder (eller foreldre når det -gjelder barn), etter en lovendring for en stund tilbake, med mindre -det er sendt inn skjema der en reserverer seg mot forskning uten -samtykke. Skjemaet er tilgjengelig fra -<a href="https://www.fhi.no/arkiv/publikasjoner/for-pasienter-skjema-for-reservasjo/">folkehelseinstituttets -websider</a>, og jeg anbefaler, uavhengig av denne saken, varmt alle å -sende inn skjemaet for å dokumentere hvor mange som ikke synes det er -greit å fjerne krav om samtykke.</p> - -<p>I tillegg bør en kreve destruering av alt biologisk materiale som -er samlet inn om en selv, for å redusere eventuelle negative -konsekvenser i fremtiden når materialet kommer på avveie eller blir -brukt uten samtykke, men det er så vidt jeg vet ikke noe system for -dette i dag.</p> - -<p>Som vanlig, hvis du bruker Bitcoin og ønsker å vise din støtte til -det jeg driver med, setter jeg pris på om du sender Bitcoin-donasjoner -til min adresse + Privacy respecting health monitor / fitness tracker? + http://people.skolelinux.org/pere/blog/Privacy_respecting_health_monitor___fitness_tracker_.html + http://people.skolelinux.org/pere/blog/Privacy_respecting_health_monitor___fitness_tracker_.html + Tue, 7 Aug 2018 16:00:00 +0200 + <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> - First rough draft Norwegian and Spanish edition of the book Made with Creative Commons - http://people.skolelinux.org/pere/blog/First_rough_draft_Norwegian_and_Spanish_edition_of_the_book_Made_with_Creative_Commons.html - http://people.skolelinux.org/pere/blog/First_rough_draft_Norwegian_and_Spanish_edition_of_the_book_Made_with_Creative_Commons.html - Tue, 13 Mar 2018 13:00:00 +0100 - <p>I am working on publishing yet another book related to Creative -Commons. This time it is a book filled with interviews and histories -from those around the globe making a living using Creative -Commons.</p> - -<p>Yesterday, after many months of hard work by several volunteer -translators, the first draft of a Norwegian Bokmål edition of the book -<a href="https://madewith.cc">Made with Creative Commons from 2017</a> -was complete. The Spanish translation is also complete, while the -Dutch, Polish, German and Ukraine edition need a lot of work. Get in -touch if you want to help make those happen, or would like to -translate into your mother tongue.</p> - -<p>The whole book project started when -<a href="http://gwolf.org/node/4102">Gunnar Wolf announced</a> that he -was going to make a Spanish edition of the book. I noticed, and -offered some input on how to make a book, based on my experience with -translating the -<a href="https://www.lulu.com/shop/lawrence-lessig/fri-kultur/paperback/product-22441576.html">Free -Culture</a> and -<a href="https://debian-handbook.info/get/#norwegian">The Debian -Administrator's Handbook</a> books to Norwegian Bokmål. To make a -long story short, we ended up working on a Bokmål edition, and now the -first rough translation is complete, thanks to the hard work of -Ole-Erik Yrvin, Ingrid Yrvin, Allan Nordhøy and myself. The first -proof reading is almost done, and only the second and third proof -reading remains. We will also need to translate the 14 figures and -create a book cover. Once it is done we will publish the book on -paper, as well as in PDF, ePub and possibly Mobi formats.</p> - -<p>The book itself originates as a manuscript on Google Docs, is -downloaded as ODT from there and converted to Markdown using pandoc. -The Markdown is modified by a script before is converted to DocBook -using pandoc. The DocBook is modified again using a script before it -is used to create a Gettext POT file for translators. The translated -PO file is then combined with the earlier mentioned DocBook file to -create a translated DocBook file, which finally is given to dblatex to -create the final PDF. The end result is a set of editions of the -manuscript, one English and one for each of the translations.</p> - -<p>The translation is conducted using -<a href="https://hosted.weblate.org/projects/madewithcc/translation/">the -Weblate web based translation system</a>. Please have a look there -and get in touch if you would like to help out with proof -reading. :)</p> + Sharing images with friends and family using RSS and EXIF/XMP metadata + http://people.skolelinux.org/pere/blog/Sharing_images_with_friends_and_family_using_RSS_and_EXIF_XMP_metadata.html + http://people.skolelinux.org/pere/blog/Sharing_images_with_friends_and_family_using_RSS_and_EXIF_XMP_metadata.html + Tue, 31 Jul 2018 23:30:00 +0200 + <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 +&lt;enclosure&gt; 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 @@ -213,47 +188,98 @@ activities, please send Bitcoin donations to my address - Debian used in the subway info screens in Oslo, Norway - http://people.skolelinux.org/pere/blog/Debian_used_in_the_subway_info_screens_in_Oslo__Norway.html - http://people.skolelinux.org/pere/blog/Debian_used_in_the_subway_info_screens_in_Oslo__Norway.html - Fri, 2 Mar 2018 13:10:00 +0100 - <p>Today I was pleasantly surprised to discover my operating system of -choice, Debian, was used in the info screens on the subway stations. -While passing Nydalen subway station in Oslo, Norway, I discovered the -info screen booting with some text scrolling. I was not quick enough -with my camera to be able to record a video of the scrolling boot -screen, but I did get a photo from when the boot got stuck with a -corrupt file system: - -<p align="center"><a href="http://people.skolelinux.org/pere/blog/images/2018-03-02-ruter-debian-lenny.jpeg"><img align="center" width="40%" src="http://people.skolelinux.org/pere/blog/images/2018-03-02-ruter-debian-lenny.jpeg" alt="[photo of subway info screen]"></a></p> - -<p>While I am happy to see Debian used more places, some details of the -content on the screen worries me.</p> - -<p>The image show the version booting is 'Debian GNU/Linux lenny/sid', -indicating that this is based on code taken from Debian Unstable/Sid -after Debian Etch (version 4) was released 2007-04-08 and before -Debian Lenny (version 5) was released 2009-02-14. Since Lenny Debian -has released version 6 (Squeeze) 2011-02-06, 7 (Wheezy) 2013-05-04, 8 -(Jessie) 2015-04-25 and 9 (Stretch) 2017-06-15, according to -<a href="https://en.wikipedia.org/wiki/Debian_version_history">a Debian -version history on Wikpedia</a>. This mean the system is running -around 10 year old code, with no security fixes from the vendor for -many years.</p> - -<p>This is not the first time I discover the Oslo subway company, -Ruter, running outdated software. In 2012, -<a href="http://people.skolelinux.org/pere/blog/Er_billettautomatene_til_kollektivtrafikken_i_Oslo_uten_sikkerhetsoppdateringer_.html">I -discovered the ticket vending machines were running Windows 2000</a>, -and this was -<a href="http://people.skolelinux.org/pere/blog/Fortsatt_ingen_sikkerhetsoppdateringer_for_billettautomatene_til_kollektivtrafikken_i_Oslo_.html">still -the case in 2016</a>. Given the response from the responsible people -in 2016, I would assume the machines are still running unpatched -Windows 2000. Thus, an unpatched Debian setup come as no surprise.</p> - -<p>The photo is made available under the license terms -<a href="http://creativecommons.org/licenses/by/4.0/">Creative Commons -4.0 Attribution International (CC BY 4.0)</a>.</p> + Simple streaming the Linux desktop to Kodi using GStreamer and RTP + http://people.skolelinux.org/pere/blog/Simple_streaming_the_Linux_desktop_to_Kodi_using_GStreamer_and_RTP.html + http://people.skolelinux.org/pere/blog/Simple_streaming_the_Linux_desktop_to_Kodi_using_GStreamer_and_RTP.html + Thu, 12 Jul 2018 17:55:00 +0200 + <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 @@ -262,32 +288,145 @@ activities, please send Bitcoin donations to my address - The SysVinit upstream project just migrated to git - http://people.skolelinux.org/pere/blog/The_SysVinit_upstream_project_just_migrated_to_git.html - http://people.skolelinux.org/pere/blog/The_SysVinit_upstream_project_just_migrated_to_git.html - Sun, 18 Feb 2018 09:20:00 +0100 - <p>Surprising as it might sound, there are still computers using the -traditional Sys V init system, and there probably will be until -systemd start working on Hurd and FreeBSD. -<a href="https://savannah.nongnu.org/projects/sysvinit">The upstream -project still exist</a>, though, and up until today, the upstream -source was available from Savannah via subversion. I am happy to -report that this just changed.</p> - -<p>The upstream source is now in Git, and consist of three -repositories:</p> - -<ul> - -<li><a href="http://git.savannah.nongnu.org/cgit/sysvinit.git">sysvinit</a></li> -<li><a href="http://git.savannah.nongnu.org/cgit/sysvinit/insserv.git">insserv</a></li> -<li><a href="http://git.savannah.nongnu.org/cgit/sysvinit/startpar.git">startpar</a></li> - -</ul> - -<p>I do not really spend much time on the project these days, and I -has mostly retired, but found it best to migrate the source to a good -version control system to help those willing to move it forward.</p> + Streaming the Linux desktop to Kodi using VLC and RTSP + http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html + http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html + Thu, 12 Jul 2018 02:00:00 +0200 + <p>PS: See +<ahref="http://people.skolelinux.org/pere/blog/Simple_streaming_the_Linux_desktop_to_Kodi_using_GStreamer_and_RTP.html">the +followup post</a> for a even better approach.</p> + +<p>A while back, I was asked by a friend how to stream the desktop to +my projector connected to Kodi. I sadly had to admit that I had no +idea, as it was a task I never had tried. Since then, I have been +looking for a way to do so, preferable without much extra software to +install on either side. Today I found a way that seem to kind of +work. Not great, but it is a start.</p> + +<p>I had a look at several approaches, for example +<a href="https://github.com/mfoetsch/dlna_live_streaming">using uPnP +DLNA as described in 2011</a>, but it required a uPnP server, fuse and +local storage enough to store the stream locally. This is not going +to work well for me, lacking enough free space, and it would +impossible for my friend to get working.</p> + +<p>Next, it occurred to me that perhaps I could use VLC to create a +video stream that Kodi could play. Preferably using +broadcast/multicast, to avoid having to change any setup on the Kodi +side when starting such stream. Unfortunately, the only recipe I +could find using multicast used the rtp protocol, and this protocol +seem to not be supported by Kodi.</p> + +<p>On the other hand, the rtsp protocol is working! Unfortunately I +have to specify the IP address of the streaming machine in both the +sending command and the file on the Kodi server. But it is showing my +desktop, and thus allow us to have a shared look on the big screen at +the programs I work on.</p> + +<p>I did not spend much time investigating codeces. I combined the +rtp and rtsp recipes from +<a href="https://wiki.videolan.org/Documentation:Streaming_HowTo/Command_Line_Examples/">the +VLC Streaming HowTo/Command Line Examples</a>, and was able to get +this working on the desktop/streaming end.</p> + +<blockquote><pre> +vlc screen:// --sout \ + '#transcode{vcodec=mp4v,acodec=mpga,vb=800,ab=128}:rtp{dst=projector.local,port=1234,sdp=rtsp://192.168.11.4:8080/test.sdp}' +</pre></blockquote> + +<p>I ssh-ed into my Kodi box and created a file like this with the +same IP address:</p> + +<blockquote><pre> +echo rtsp://192.168.11.4:8080/test.sdp \ + > /storage/videos/screenstream.m3u +</pre></blockquote> + +<p>Note the 192.168.11.4 IP address is my desktops IP address. As far +as I can tell the IP must be hardcoded for this to work. In other +words, if someone elses machine is going to do the steaming, you have +to update screenstream.m3u on the Kodi machine and adjust the vlc +recipe. To get started, locate the file in Kodi and select the m3u +file while the VLC stream is running. The desktop then show up in my +big screen. :)</p> + +<p>When using the same technique to stream a video file with audio, +the audio quality is really bad. No idea if the problem is package +loss or bad parameters for the transcode. I do not know VLC nor Kodi +enough to tell.</p> + +<p><strong>Update 2018-07-12</strong>: Johannes Schauer send me a few +succestions and reminded me about an important step. The "screen:" +input source is only available once the vlc-plugin-access-extra +package is installed on Debian. Without it, you will see this error +message: "VLC is unable to open the MRL 'screen://'. Check the log +for details." He further found that it is possible to drop some parts +of the VLC command line to reduce the amount of hardcoded information. +It is also useful to consider using cvlc to avoid having the VLC +window in the desktop view. In sum, this give us this command line on +the source end + +<blockquote><pre> +cvlc screen:// --sout \ + '#transcode{vcodec=mp4v,acodec=mpga,vb=800,ab=128}:rtp{sdp=rtsp://:8080/}' +</pre></blockquote> + +<p>and this on the Kodi end<p> + +<blockquote><pre> +echo rtsp://192.168.11.4:8080/ \ + > /storage/videos/screenstream.m3u +</pre></blockquote> + +<p>Still bad image quality, though. But I did discover that streaming +a DVD using dvdsimple:///dev/dvd as the source had excellent video and +audio quality, so I guess the issue is in the input or transcoding +parts, not the rtsp part. I've tried to change the vb and ab +parameters to use more bandwidth, but it did not make a +difference.</p> + +<p>I further received a suggestion from Einar Haraldseid to try using +gstreamer instead of VLC, and this proved to work great! He also +provided me with the trick to get Kodi to use a multicast stream as +its source. By using this monstrous oneliner, I can stream my desktop +with good video quality in reasonable framerate to the 239.255.0.1 +multicast address on port 1234: + +<blockquote><pre> +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=239.255.0.1 port=1234 ttl-mc=1 auto-multicast=1 sync=0 \ + pulsesrc device=$(pactl list | grep -A2 'Source #' | \ + grep 'Name: .*\.monitor$' | cut -d" " -f2|head -1) ! \ + audioconvert ! queue2 ! avenc_aac ! queue2 ! mux. +</pre></blockquote> + +<p>and this on the Kodi end<p> + +<blockquote><pre> +echo udp://@239.255.0.1:1234 \ + > /storage/videos/screenstream.m3u +</pre></blockquote> + +<p>Note the trick to pick a valid pulseaudio source. It might not +pick the one you need. This approach will of course lead to trouble +if more than one source uses the same multicast port and address. +Note the ttl-mc=1 setting, which limit the multicast packages to the +local network. If the value is increased, your screen will be +broadcasted further, one network "hop" for each increase (read up on +multicast to learn more. :)!</p> + +<p>Having cracked how to get Kodi to receive multicast streams, I +could use this VLC command to stream to the same multicast address. +The image quality is way better than the rtsp approach, but gstreamer +seem to be doing a better job.</p> + +<blockquote><pre> +cvlc screen:// --sout '#transcode{vcodec=mp4v,acodec=mpga,vb=800,ab=128}:rtp{mux=ts,dst=239.255.0.1,port=1234,sdp=sap}' +</pre></blockquote> <p>As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address @@ -296,72 +435,114 @@ activities, please send Bitcoin donations to my address - Using VLC to stream bittorrent sources - http://people.skolelinux.org/pere/blog/Using_VLC_to_stream_bittorrent_sources.html - http://people.skolelinux.org/pere/blog/Using_VLC_to_stream_bittorrent_sources.html - Wed, 14 Feb 2018 08:00:00 +0100 - <p>A few days ago, a new major version of -<a href="https://www.videolan.org/">VLC</a> was announced, and I -decided to check out if it now supported streaming over -<a href="http://bittorrent.org/">bittorrent</a> and -<a href="https://webtorrent.io">webtorrent</a>. Bittorrent is one of -the most efficient ways to distribute large files on the Internet, and -Webtorrent is a variant of Bittorrent using -<a href="https://webrtc.org">WebRTC</a> as its transport channel, -allowing web pages to stream and share files using the same technique. -The network protocols are similar but not identical, so a client -supporting one of them can not talk to a client supporting the other. -I was a bit surprised with what I discovered when I started to look. -Looking at -<a href="https://www.videolan.org/vlc/releases/3.0.0.html">the release -notes</a> did not help answering this question, so I started searching -the web. I found several news articles from 2013, most of them -tracing the news from Torrentfreak -("<a href=https://torrentfreak.com/open-source-giant-vlc-mulls-bittorrent-support-130211/">Open -Source Giant VLC Mulls BitTorrent Streaming Support</a>"), about a -initiative to pay someone to create a VLC patch for bittorrent -support. To figure out what happend with this initiative, I headed -over to the #videolan IRC channel and asked if there were some bug or -feature request tickets tracking such feature. I got an answer from -lead developer Jean-Babtiste Kempf, telling me that there was a patch -but neither he nor anyone else knew where it was. So I searched a bit -more, and came across an independent -<a href="https://github.com/johang/vlc-bittorrent">VLC plugin to add -bittorrent support</a>, created by Johan Gunnarsson in 2016/2017. -Again according to Jean-Babtiste, this is not the patch he was talking -about.</p> - -<p>Anyway, to test the plugin, I made a working Debian package from -the git repository, with some modifications. After installing this -package, I could stream videos from -<a href="https://www.archive.org/">The Internet Archive</a> using VLC -commands like this:</p> + What is the most supported MIME type in Debian in 2018? + http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_in_2018_.html + http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_in_2018_.html + Mon, 9 Jul 2018 08:05:00 +0200 + <p>Five years ago, +<a href="http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_.html">I +measured what the most supported MIME type in Debian was</a>, by +analysing the desktop files in all packages in the archive. Since +then, the DEP-11 AppStream system has been put into production, making +the task a lot easier. This made me want to repeat the measurement, +to see how much things changed. Here are the new numbers, for +unstable only this time: + +<p><strong>Debian Unstable:</strong></p> + +<pre> + count MIME type + ----- ----------------------- + 56 image/jpeg + 55 image/png + 49 image/tiff + 48 image/gif + 39 image/bmp + 38 text/plain + 37 audio/mpeg + 34 application/ogg + 33 audio/x-flac + 32 audio/x-mp3 + 30 audio/x-wav + 30 audio/x-vorbis+ogg + 29 image/x-portable-pixmap + 27 inode/directory + 27 image/x-portable-bitmap + 27 audio/x-mpeg + 26 application/x-ogg + 25 audio/x-mpegurl + 25 audio/ogg + 24 text/html +</pre> + +<p>The list was created like this using a sid chroot: "cat +/var/lib/apt/lists/*sid*_dep11_Components-amd64.yml.gz| zcat | awk '/^ +- \S+\/\S+$/ {print $2 }' | sort | uniq -c | sort -nr | head -20"</p> + +<p>It is interesting to see how image formats have passed text/plain +as the most announced supported MIME type. These days, thanks to the +AppStream system, if you run into a file format you do not know, and +want to figure out which packages support the format, you can find the +MIME type of the file using "file --mime &lt;filename&gt;", and then +look up all packages announcing support for this format in their +AppStream metadata (XML or .desktop file) using "appstreamcli +what-provides mimetype &lt;mime-type&gt;. For example if you, like +me, want to know which packages support inode/directory, you can get a +list like this:</p> <p><blockquote><pre> -vlc https://archive.org/download/LoveNest/LoveNest_archive.torrent +% appstreamcli what-provides mimetype inode/directory | grep Package: | sort +Package: anjuta +Package: audacious +Package: baobab +Package: cervisia +Package: chirp +Package: dolphin +Package: doublecmd-common +Package: easytag +Package: enlightenment +Package: ephoto +Package: filelight +Package: gwenview +Package: k4dirstat +Package: kaffeine +Package: kdesvn +Package: kid3 +Package: kid3-qt +Package: nautilus +Package: nemo +Package: pcmanfm +Package: pcmanfm-qt +Package: qweborf +Package: ranger +Package: sirikali +Package: spacefm +Package: spacefm +Package: vifm +% </pre></blockquote></p> -<p>The plugin is supposed to handle magnet links too, but since The -Internet Archive do not have magnet links and I did not want to spend -time tracking down another source, I have not tested it. It can take -quite a while before the video start playing without any indication of -what is going on from VLC. It took 10-20 seconds when I measured it. -Some times the plugin seem unable to find the correct video file to -play, and show the metadata XML file name in the VLC status line. I -have no idea why.</p> - -<p>I have created a <a href="https://bugs.debian.org/890360">request for -a new package in Debian (RFP)</a> and -<a href="https://github.com/johang/vlc-bittorrent/issues/1">asked if -the upstream author is willing to help make this happen</a>. Now we -wait to see what come out of this. I do not want to maintain a -package that is not maintained upstream, nor do I really have time to -maintain more packages myself, so I might leave it at this. But I -really hope someone step up to do the packaging, and hope upstream is -still maintaining the source. If you want to help, please update the -RFP request or the upstream issue.</p> - -<p>I have not found any traces of webtorrent support for VLC.</p> +<p>Using the same method, I can quickly discover that the Sketchup file +format is not yet supported by any package in Debian:</p> + +<p><blockquote><pre> +% appstreamcli what-provides mimetype application/vnd.sketchup.skp +Could not find component providing 'mimetype::application/vnd.sketchup.skp'. +% +</pre></blockquote></p> + +<p>Yesterday I used it to figure out which packages support the STL 3D +format:</p> + +<p><blockquote><pre> +% appstreamcli what-provides mimetype application/sla|grep Package +Package: cura +Package: meshlab +Package: printrun +% +</pre></blockquote></p> + +<p>PS: A new version of Cura was uploaded to Debian yesterday.</p> <p>As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address @@ -370,25 +551,76 @@ activities, please send Bitcoin donations to my address - Version 3.1 of Cura, the 3D print slicer, is now in Debian - http://people.skolelinux.org/pere/blog/Version_3_1_of_Cura__the_3D_print_slicer__is_now_in_Debian.html - http://people.skolelinux.org/pere/blog/Version_3_1_of_Cura__the_3D_print_slicer__is_now_in_Debian.html - Tue, 13 Feb 2018 06:20:00 +0100 - <p>A new version of the -<a href="https://tracker.debian.org/pkg/cura">3D printer slicer -software Cura</a>, version 3.1.0, is now available in Debian Testing -(aka Buster) and Debian Unstable (aka Sid). I hope you find it -useful. It was uploaded the last few days, and the last update will -enter testing tomorrow. See the -<a href="https://ultimaker.com/en/products/cura-software/release-notes">release -notes</a> for the list of bug fixes and new features. Version 3.2 -was announced 6 days ago. We will try to get it into Debian as -well.</p> - -<p>More information related to 3D printing is available on the -<a href="https://wiki.debian.org/3DPrinting">3D printing</a> and -<a href="https://wiki.debian.org/3D-printer">3D printer</a> wiki pages -in Debian.</p> + Debian APT upgrade without enough free space on the disk... + http://people.skolelinux.org/pere/blog/Debian_APT_upgrade_without_enough_free_space_on_the_disk___.html + http://people.skolelinux.org/pere/blog/Debian_APT_upgrade_without_enough_free_space_on_the_disk___.html + Sun, 8 Jul 2018 12:10:00 +0200 + <p>Quite regularly, I let my Debian Sid/Unstable chroot stay untouch +for a while, and when I need to update it there is not enough free +space on the disk for apt to do a normal 'apt upgrade'. I normally +would resolve the issue by doing 'apt install &lt;somepackages&gt;' to +upgrade only some of the packages in one batch, until the amount of +packages to download fall below the amount of free space available. +Today, I had about 500 packages to upgrade, and after a while I got +tired of trying to install chunks of packages manually. I concluded +that I did not have the spare hours required to complete the task, and +decided to see if I could automate it. I came up with this small +script which I call 'apt-in-chunks':</p> + +<p><blockquote><pre> +#!/bin/sh +# +# Upgrade packages when the disk is too full to upgrade every +# upgradable package in one lump. Fetching packages to upgrade using +# apt, and then installing using dpkg, to avoid changing the package +# flag for manual/automatic. + +set -e + +ignore() { + if [ "$1" ]; then + grep -v "$1" + else + cat + fi +} + +for p in $(apt list --upgradable | ignore "$@" |cut -d/ -f1 | grep -v '^Listing...'); do + echo "Upgrading $p" + apt clean + apt install --download-only -y $p + for f in /var/cache/apt/archives/*.deb; do + if [ -e "$f" ]; then + dpkg -i /var/cache/apt/archives/*.deb + break + fi + done +done +</pre></blockquote></p> + +<p>The script will extract the list of packages to upgrade, try to +download the packages needed to upgrade one package, install the +downloaded packages using dpkg. The idea is to upgrade packages +without changing the APT mark for the package (ie the one recording of +the package was manually requested or pulled in as a dependency). To +use it, simply run it as root from the command line. If it fail, try +'apt install -f' to clean up the mess and run the script again. This +might happen if the new packages conflict with one of the old +packages. dpkg is unable to remove, while apt can do this.</p> + +<p>It take one option, a package to ignore in the list of packages to +upgrade. The option to ignore a package is there to be able to skip +the packages that are simply too large to unpack. Today this was +'ghc', but I have run into other large packages causing similar +problems earlier (like TeX).</p> + +<p>Update 2018-07-08: Thanks to Paul Wise, I am aware of two +alternative ways to handle this. The "unattended-upgrades +--minimal-upgrade-steps" option will try to calculate upgrade sets for +each package to upgrade, and then upgrade them in order, smallest set +first. It might be a better option than my above mentioned script. +Also, "aptutude upgrade" can upgrade single packages, thus avoiding +the need for using "dpkg -i" in the script above.</p> <p>As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address @@ -397,135 +629,86 @@ activities, please send Bitcoin donations to my address - Overvåkning i Kina vs. Norge - http://people.skolelinux.org/pere/blog/Overv_kning_i_Kina_vs__Norge.html - http://people.skolelinux.org/pere/blog/Overv_kning_i_Kina_vs__Norge.html - Mon, 12 Feb 2018 09:40:00 +0100 - <p>Jeg lar meg fascinere av en artikkel -<a href="https://www.dagbladet.no/kultur/terroristene-star-pa-dora/69436116">i -Dagbladet om Kinas håndtering av Xinjiang</a>, spesielt følgende -utsnitt:</p> - -<p><blockquote> - -<p>«I den sørvestlige byen Kashgar nærmere grensa til -Sentral-Asia meldes det nå at 120.000 uigurer er internert i såkalte -omskoleringsleirer. Samtidig er det innført et omfattende -helsesjekk-program med innsamling og lagring av DNA-prøver fra -absolutt alle innbyggerne. De mest avanserte overvåkingsmetodene -testes ut her. Programmer for å gjenkjenne ansikter og stemmer er på -plass i regionen. Der har de lokale myndighetene begynt å installere -GPS-systemer i alle kjøretøy og egne sporingsapper i -mobiltelefoner.</p> - -<p>Politimetodene griper så dypt inn i folks dagligliv at motstanden -mot Beijing-regimet øker.»</p> - -</blockquote></p> - -<p>Beskrivelsen avviker jo desverre ikke så veldig mye fra tilstanden -her i Norge.</p> - -<table> -<tr> -<th>Dataregistrering</th> -<th>Kina</th> -<th>Norge</th> - -<tr> -<td>Innsamling og lagring av DNA-prøver fra befolkningen</td> -<td>Ja</td> -<td>Delvis, planlagt for alle nyfødte.</td> -</tr> - -<tr> -<td>Ansiktsgjenkjenning</td> -<td>Ja</td> -<td>Ja</td> -</tr> - -<tr> -<td>Stemmegjenkjenning</td> -<td>Ja</td> -<td>Nei</td> -</tr> - -<tr> -<td>Posisjons-sporing av mobiltelefoner</td> -<td>Ja</td> -<td>Ja</td> -</tr> - -<tr> -<td>Posisjons-sporing av biler</td> -<td>Ja</td> -<td>Ja</td> -</tr> - -</table> - -<p>I Norge har jo situasjonen rundt Folkehelseinstituttets lagring av -DNA-informasjon på vegne av politiet, der de nektet å slette -informasjon politiet ikke hadde lov til å ta vare på, gjort det klart -at DNA tar vare på ganske lenge. I tillegg finnes det utallige -biobanker som lagres til evig tid, og det er planer om å innføre -<a href="https://www.aftenposten.no/norge/i/75E9/4-av-10-mener-staten-bor-lagre-DNA-profiler-pa-alle-nyfodte">evig -lagring av DNA-materiale fra alle spebarn som fødes</a> (med mulighet -for å be om sletting).</p> - -<p>I Norge er det system på plass for ansiktsgjenkjenning, som -<a href="https://www.nrk.no/norge/kun-gardermoen-har-teknologi-for-ansiktsgjenkjenning-i-norge-1.12719461">en -NRK-artikkel fra 2015</a> forteller er aktiv på Gardermoen, samt -<a href="https://www.dagbladet.no/nyheter/inntil-27-000-bor-i-norge-under-falsk-id/60500781">brukes -til å analysere bilder innsamlet av myndighetene</a>. Brukes det også -flere plasser? Det er tett med overvåkningskamera kontrollert av -politi og andre myndigheter i for eksempel Oslo sentrum.</p> - -<p>Jeg er ikke kjent med at Norge har noe system for identifisering av -personer ved hjelp av stemmegjenkjenning.</p> - -<p>Posisjons-sporing av mobiltelefoner er ruinemessig tilgjengelig for -blant annet politi, NAV og Finanstilsynet, i tråd med krav i -telefonselskapenes konsesjon. I tillegg rapporterer smarttelefoner -sin posisjon til utviklerne av utallige mobil-apper, der myndigheter -og andre kan hente ut informasjon ved behov. Det er intet behov for -noen egen app for dette.</p> - -<p>Posisjons-sporing av biler er rutinemessig tilgjengelig via et tett -nett av målepunkter på veiene (automatiske bomstasjoner, -køfribrikke-registrering, automatiske fartsmålere og andre veikamera). -Det er i tillegg vedtatt at alle nye biler skal selges med utstyr for -GPS-sporing (eCall).</p> - -<p>Det er jammen godt vi lever i et liberalt demokrati, og ikke en -overvåkningsstat, eller?</p> - -<p>Som vanlig, hvis du bruker Bitcoin og ønsker å vise din støtte til -det jeg driver med, setter jeg pris på om du sender Bitcoin-donasjoner -til min adresse + The worlds only stone power plant? + http://people.skolelinux.org/pere/blog/The_worlds_only_stone_power_plant_.html + http://people.skolelinux.org/pere/blog/The_worlds_only_stone_power_plant_.html + Sat, 30 Jun 2018 10:35:00 +0200 + <p>So far, at least hydro-electric power, coal power, wind power, +solar power, and wood power are well known. Until a few days ago, I +had never heard of stone power. Then I learn about a quarry in a +mountain in +<a href="https://en.wikipedia.org/wiki/Bremanger">Bremanger</a> i +Norway, where +<a href="https://www.bontrup.com/en/activities/raw-materials/bremanger-quarry/">the +Bremanger Quarry</a> company is extracting stone and dumping the stone +into a shaft leading to its shipping harbour. This downward movement +in this shaft is used to produce electricity. In short, it is using +falling rocks instead of falling water to produce electricity, and +according to its own statements it is producing more power than it is +using, and selling the surplus electricity to the Norwegian power +grid. I find the concept truly amazing. Is this the worlds only +stone power plant?</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> - How hard can æ, ø and å be? - http://people.skolelinux.org/pere/blog/How_hard_can______and___be_.html - http://people.skolelinux.org/pere/blog/How_hard_can______and___be_.html - Sun, 11 Feb 2018 17:10:00 +0100 - <img src="http://people.skolelinux.org/pere/blog/images/2018-02-11-peppes-unicode.jpeg" align="right"/> - -<p>We write 2018, and it is 30 years since Unicode was introduced. -Most of us in Norway have come to expect the use of our alphabet to -just work with any computer system. But it is apparently beyond reach -of the computers printing recites at a restaurant. Recently I visited -a Peppes pizza resturant, and noticed a few details on the recite. -Notice how 'ø' and 'å' are replaced with strange symbols in -'Servitør', 'Å BETALE', 'Beløp pr. gjest', 'Takk for besøket.' and 'Vi -gleder oss til å se deg igjen'.</p> - -<p>I would say that this state is passed sad and over in embarrassing.</p> - -<p>I removed personal and private information to be nice.</p> + Add-on to control the projector from within Kodi + http://people.skolelinux.org/pere/blog/Add_on_to_control_the_projector_from_within_Kodi.html + http://people.skolelinux.org/pere/blog/Add_on_to_control_the_projector_from_within_Kodi.html + Tue, 26 Jun 2018 23:55:00 +0200 + <p>My movie playing setup involve <a href="https://kodi.tv/">Kodi</a>, +<a href="https://openelec.tv">OpenELEC</a> (probably soon to be +replaced with <a href="https://libreelec.tv/">LibreELEC</a>) and an +Infocus IN76 video projector. My projector can be controlled via both +a infrared remote controller, and a RS-232 serial line. The vendor of +my projector, <a href="https://www.infocus.com/">InFocus</a>, had been +sensible enough to document the serial protocol in its user manual, so +it is easily available, and I used it some years ago to write +<a href="https://github.com/petterreinholdtsen/infocus-projector-control">a +small script to control the projector</a>. For a while now, I longed +for a setup where the projector was controlled by Kodi, for example in +such a way that when the screen saver went on, the projector was +turned off, and when the screen saver exited, the projector was turned +on again.</p> + +<p>A few days ago, with very good help from parts of my family, I +managed to find a Kodi Add-on for controlling a Epson projector, and +got in touch with its author to see if we could join forces and make a +Add-on with support for several projectors. To my pleasure, he was +positive to the idea, and we set out to add InFocus support to his +add-on, and make the add-on suitable for the official Kodi add-on +repository.</p> + +<p>The Add-on is now working (for me, at least), with a few minor +adjustments. The most important change I do relative to the master +branch in the github repository is embedding the +<a href="https://github.com/pyserial/pyserial">pyserial module</a> in +the add-on. The long term solution is to make a "script" type +pyserial module for Kodi, that can be pulled in as a dependency in +Kodi. But until that in place, I embed it.</p> + +<p>The add-on can be configured to turn on the projector when Kodi +starts, off when Kodi stops as well as turn the projector off when the +screensaver start and on when the screesaver stops. It can also be +told to set the projector source when turning on the projector. + +<p>If this sound interesting to you, check out +<a href="https://github.com/fredrik-eriksson/kodi_projcontrol">the +project github repository</a>. Perhaps you can send patches to +support your projector too? As soon as we find time to wrap up the +latest changes, it should be available for easy installation using any +Kodi instance.</p> + +<p>For future improvements, I would like to add projector model +detection and the ability to adjust the brightness level of the +projector from within Kodi. We also need to figure out how to handle +the cooling period of the projector. My projector refuses to turn on +for 60 seconds after it was turned off. This is not handled well by +the add-on at the moment.</p> <p>As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address