X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/fe355b44be0993da52a8c9858be208dae3fd3bd2..2aafae50dc90da8ae2432aaeca9569fbe49cf7d7:/blog/index.rss diff --git a/blog/index.rss b/blog/index.rss index a642378182..0581cf3d48 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -7,593 +7,712 @@ - Datalagringsdirektivet kaster skygger over Høyre og Arbeiderpartiet - http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_kaster_skygger_over_H_yre_og_Arbeiderpartiet.html - http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_kaster_skygger_over_H_yre_og_Arbeiderpartiet.html - Thu, 7 Sep 2017 21:35:00 +0200 - <p>For noen dager siden publiserte Jon Wessel-Aas en bloggpost om -«<a href="http://www.uhuru.biz/?p=1821">Konklusjonen om datalagring som -EU-kommisjonen ikke ville at vi skulle få se</a>». Det er en -interessant gjennomgang av EU-domstolens syn på snurpenotovervåkning -av befolkningen, som er klar på at det er i strid med -EU-lovgivingen.</p> - -<p>Valgkampen går for fullt i Norge, og om noen få dager er siste -frist for å avgi stemme. En ting er sikkert, Høyre og Arbeiderpartiet -får ikke min stemme -<a href="http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_gj_r_at_Oslo_H_yre_og_Arbeiderparti_ikke_f_r_min_stemme_i__r.html">denne -gangen heller</a>. Jeg har ikke glemt at de tvang igjennom loven som -skulle pålegge alle data- og teletjenesteleverandører å overvåke alle -sine kunder. En lov som er vedtatt, og aldri opphevet igjen.</p> - -<p>Det er tydelig fra diskusjonen rundt grenseløs digital overvåkning -(eller "Digital Grenseforsvar" som det kalles i Orvellisk nytale) at -hverken Høyre og Arbeiderpartiet har noen prinsipielle sperrer mot å -overvåke hele befolkningen, og diskusjonen så langt tyder på at flere -av de andre partiene heller ikke har det. Mange av -<a href="https://data.holderdeord.no/votes/1301946411e">de som stemte -for Datalagringsdirektivet i Stortinget</a> (64 fra Arbeiderpartiet, -25 fra Høyre) er fortsatt aktive og argumenterer fortsatt for å radere -vekk mer av innbyggernes privatsfære.</p> - -<p>Når myndighetene demonstrerer sin mistillit til folket, tror jeg -folket selv bør legge litt innsats i å verne sitt privatliv, ved å ta -i bruk ende-til-ende-kryptert kommunikasjon med sine kjente og kjære, -og begrense hvor mye privat informasjon som deles med uvedkommende. -Det er jo ingenting som tyder på at myndighetene kommer til å være vår -privatsfære. -<a href="http://people.skolelinux.org/pere/blog/How_to_talk_with_your_loved_ones_in_private.html">Det -er mange muligheter</a>. Selv har jeg litt sans for -<a href="https://ring.cx/">Ring</a>, som er basert på p2p-teknologi -uten sentral kontroll, er fri programvare, og støtter meldinger, tale -og video. Systemet er tilgjengelig ut av boksen fra -<a href="https://tracker.debian.org/pkg/ring">Debian</a> og -<a href="https://launchpad.net/ubuntu/+source/ring">Ubuntu</a>, og det -finnes pakker for Android, MacOSX og Windows. Foreløpig er det få -brukere med Ring, slik at jeg også bruker -<a href="https://signal.org/">Signal</a> som nettleserutvidelse.</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> - Simpler recipe on how to make a simple $7 IMSI Catcher using Debian - http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html - http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html - Wed, 9 Aug 2017 23:59:00 +0200 - <p>On friday, I came across an interesting article in the Norwegian -web based ICT news magazine digi.no on -<a href="https://www.digi.no/artikler/sikkerhetsforsker-lagde-enkel-imsi-catcher-for-60-kroner-na-kan-mobiler-kartlegges-av-alle/398588">how -to collect the IMSI numbers of nearby cell phones</a> using the cheap -DVB-T software defined radios. The article refered to instructions -and <a href="https://www.youtube.com/watch?v=UjwgNd_as30">a recipe by -Keld Norman on Youtube on how to make a simple $7 IMSI Catcher</a>, and I decided to test them out.</p> - -<p>The instructions said to use Ubuntu, install pip using apt (to -bypass apt), use pip to install pybombs (to bypass both apt and pip), -and the ask pybombs to fetch and build everything you need from -scratch. I wanted to see if I could do the same on the most recent -Debian packages, but this did not work because pybombs tried to build -stuff that no longer build with the most recent openssl library or -some other version skew problem. While trying to get this recipe -working, I learned that the apt->pip->pybombs route was a long detour, -and the only piece of software dependency missing in Debian was the -gr-gsm package. I also found out that the lead upstream developer of -gr-gsm (the name stand for GNU Radio GSM) project already had a set of -Debian packages provided in an Ubuntu PPA repository. All I needed to -do was to dget the Debian source package and built it.</p> - -<p>The IMSI collector is a python script listening for packages on the -loopback network device and printing to the terminal some specific GSM -packages with IMSI numbers in them. The code is fairly short and easy -to understand. The reason this work is because gr-gsm include a tool -to read GSM data from a software defined radio like a DVB-T USB stick -and other software defined radios, decode them and inject them into a -network device on your Linux machine (using the loopback device by -default). This proved to work just fine, and I've been testing the -collector for a few days now.</p> - -<p>The updated and simpler recipe is thus to</p> - -<ol> - -<li>start with a Debian machine running Stretch or newer,</li> - -<li>build and install the gr-gsm package available from -<a href="http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/">http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/</a>,</li> - -<li>clone the git repostory from <a href="https://github.com/Oros42/IMSI-catcher">https://github.com/Oros42/IMSI-catcher</a>,</li> - -<li>run grgsm_livemon and adjust the frequency until the terminal -where it was started is filled with a stream of text (meaning you -found a GSM station).</li> - -<li>go into the IMSI-catcher directory and run 'sudo python simple_IMSI-catcher.py' to extract the IMSI numbers.</li> - -</ol> - -<p>To make it even easier in the future to get this sniffer up and -running, I decided to package -<a href="https://github.com/ptrkrysik/gr-gsm/">the gr-gsm project</a> -for Debian (<a href="https://bugs.debian.org/871055">WNPP -#871055</a>), and the package was uploaded into the NEW queue today. -Luckily the gnuradio maintainer has promised to help me, as I do not -know much about gnuradio stuff yet.</p> - -<p>I doubt this "IMSI cacher" is anywhere near as powerfull as -commercial tools like -<a href="https://www.thespyphone.com/portable-imsi-imei-catcher/">The -Spy Phone Portable IMSI / IMEI Catcher</a> or the -<a href="https://en.wikipedia.org/wiki/Stingray_phone_tracker">Harris -Stingray</a>, but I hope the existance of cheap alternatives can make -more people realise how their whereabouts when carrying a cell phone -is easily tracked. Seeing the data flow on the screen, realizing that -I live close to a police station and knowing that the police is also -wearing cell phones, I wonder how hard it would be for criminals to -track the position of the police officers to discover when there are -police near by, or for foreign military forces to track the location -of the Norwegian military forces, or for anyone to track the location -of government officials...</p> - -<p>It is worth noting that the data reported by the IMSI-catcher -script mentioned above is only a fraction of the data broadcasted on -the GSM network. It will only collect one frequency at the time, -while a typical phone will be using several frequencies, and not all -phones will be using the frequencies tracked by the grgsm_livemod -program. Also, there is a lot of radio chatter being ignored by the -simple_IMSI-catcher script, which would be collected by extending the -parser code. I wonder if gr-gsm can be set up to listen to more than -one frequency?</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> - Norwegian Bokmål edition of Debian Administrator's Handbook is now available - http://people.skolelinux.org/pere/blog/Norwegian_Bokm_l_edition_of_Debian_Administrator_s_Handbook_is_now_available.html - http://people.skolelinux.org/pere/blog/Norwegian_Bokm_l_edition_of_Debian_Administrator_s_Handbook_is_now_available.html - Tue, 25 Jul 2017 21:10:00 +0200 - <p align="center"><img align="center" src="http://people.skolelinux.org/pere/blog/images/2017-07-25-debian-handbook-nb-testprint.png"/></p> - -<p>I finally received a copy of the Norwegian Bokmål edition of -"<a href="https://debian-handbook.info/">The Debian Administrator's -Handbook</a>". This test copy arrived in the mail a few days ago, and -I am very happy to hold the result in my hand. We spent around one and a half year translating it. This paperbook edition -<a href="https://debian-handbook.info/get/#norwegian">is available -from lulu.com</a>. If you buy it quickly, you save 25% on the list -price. The book is also available for download in electronic form as -PDF, EPUB and Mobipocket, as can be -<a href="https://debian-handbook.info/browse/nb-NO/stable/">read online -as a web page</a>.</p> - -<p>This is the second book I publish (the first was the book -"<a href="http://free-culture.cc/">Free Culture</a>" by Lawrence Lessig -in -<a href="http://www.lulu.com/shop/lawrence-lessig/free-culture/paperback/product-22440520.html">English</a>, -<a href="http://www.lulu.com/shop/lawrence-lessig/culture-libre/paperback/product-22645082.html">French</a> -and -<a href="http://www.lulu.com/shop/lawrence-lessig/fri-kultur/paperback/product-22441576.html">Norwegian -Bokmål</a>), and I am very excited to finally wrap up this -project. I hope -"<a href="http://www.lulu.com/shop/rapha%C3%ABl-hertzog-and-roland-mas/h%C3%A5ndbok-for-debian-administratoren/paperback/product-23262290.html">Håndbok -for Debian-administratoren</a>" will be well received.</p> + 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> - «Rapporten ser ikke på informasjonssikkerhet knyttet til personlig integritet» - http://people.skolelinux.org/pere/blog/_Rapporten_ser_ikke_p__informasjonssikkerhet_knyttet_til_personlig_integritet_.html - http://people.skolelinux.org/pere/blog/_Rapporten_ser_ikke_p__informasjonssikkerhet_knyttet_til_personlig_integritet_.html - Tue, 27 Jun 2017 17:50:00 +0200 - <p>Jeg kom over teksten -«<a href="https://freedom-to-tinker.com/2017/06/21/killing-car-privacy-by-federal-mandate/">Killing -car privacy by federal mandate</a>» av Leonid Reyzin på Freedom to -Tinker i dag, og det gleder meg å se en god gjennomgang om hvorfor det -er et urimelig inngrep i privatsfæren å la alle biler kringkaste sin -posisjon og bevegelse via radio. Det omtalte forslaget basert på -Dedicated Short Range Communication (DSRC) kalles Basic Safety Message -(BSM) i USA og Cooperative Awareness Message (CAM) i Europa, og det -norske Vegvesenet er en av de som ser ut til å kunne tenke seg å -pålegge alle biler å fjerne nok en bit av innbyggernes privatsfære. -Anbefaler alle å lese det som står der. - -<p>Mens jeg tittet litt på DSRC på biler i Norge kom jeg over et sitat -jeg synes er illustrativt for hvordan det offentlige Norge håndterer -problemstillinger rundt innbyggernes privatsfære i SINTEF-rapporten -«<a href="https://www.sintef.no/publikasjoner/publikasjon/Download/?pubid=SINTEF+A23933">Informasjonssikkerhet -i AutoPASS-brikker</a>» av Trond Foss:</p> - -<p><blockquote> -«Rapporten ser ikke på informasjonssikkerhet knyttet til personlig - integritet.» -</blockquote></p> - -<p>Så enkelt kan det tydeligvis gjøres når en vurderer -informasjonssikkerheten. Det holder vel at folkene på toppen kan si -at «Personvernet er ivaretatt», som jo er den populære intetsigende -frasen som gjør at mange tror enkeltindividers integritet tas vare på. -Sitatet fikk meg til å undres på hvor ofte samme tilnærming, å bare se -bort fra behovet for personlig itegritet, blir valgt når en velger å -legge til rette for nok et inngrep i privatsfæren til personer i -Norge. Det er jo sjelden det får reaksjoner. Historien om -reaksjonene på Helse Sør-Østs tjenesteutsetting er jo sørgelig nok et -unntak og toppen av isfjellet, desverre. Tror jeg fortsatt takker nei -til både AutoPASS og holder meg så langt unna det norske helsevesenet -som jeg kan, inntil de har demonstrert og dokumentert at de verdsetter -individets privatsfære og personlige integritet høyere enn kortsiktig -gevist og samfunnsnytte.</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 +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Updated sales number for my Free Culture paper editions - http://people.skolelinux.org/pere/blog/Updated_sales_number_for_my_Free_Culture_paper_editions.html - http://people.skolelinux.org/pere/blog/Updated_sales_number_for_my_Free_Culture_paper_editions.html - Mon, 12 Jun 2017 11:40:00 +0200 - <p>It is pleasing to see that the work we put down in publishing new -editions of the classic <a href="http://www.free-culture.cc/">Free -Culture book</a> by the founder of the Creative Commons movement, -Lawrence Lessig, is still being appreciated. I had a look at the -latest sales numbers for the paper edition today. Not too impressive, -but happy to see some buyers still exist. All the revenue from the -books is sent to the <a href="https://creativecommons.org/">Creative -Commons Corporation</a>, and they receive the largest cut if you buy -directly from Lulu. Most books are sold via Amazon, with Ingram -second and only a small fraction directly from Lulu. The ebook -edition is available for free from -<a href="https://github.com/petterreinholdtsen/free-culture-lessig">Github</a>.</p> - -<table border="0"> -<tr><th rowspan="2" valign="bottom">Title / language</th><th colspan="3">Quantity</th></tr> -<tr><th>2016 jan-jun</th><th>2016 jul-dec</th><th>2017 jan-may</th></tr> - -<tr> - <td><a href="http://www.lulu.com/shop/lawrence-lessig/culture-libre/paperback/product-22645082.html">Culture Libre / French</a></td> - <td align="right">3</td> - <td align="right">6</td> - <td align="right">15</td> -</tr> - -<tr> - <td><a href="http://www.lulu.com/shop/lawrence-lessig/fri-kultur/paperback/product-22441576.html">Fri kultur / Norwegian</a></td> - <td align="right">7</td> - <td align="right">1</td> - <td align="right">0</td> -</tr> - -<tr> - <td><a href="http://www.lulu.com/shop/lawrence-lessig/free-culture/paperback/product-22440520.html">Free Culture / English</a></td> - <td align="right">14</td> - <td align="right">27</td> - <td align="right">16</td> -</tr> - -<tr> - <td>Total</td> - <td align="right">24</td> - <td align="right">34</td> - <td align="right">31</td> -</tr> - -</table> - -<p>A bit sad to see the low sales number on the Norwegian edition, and -a bit surprising the English edition still selling so well.</p> - -<p>If you would like to translate and publish the book in your native -language, I would be happy to help make it happen. Please get in -touch.</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 +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Release 0.1.1 of free software archive system Nikita announced - http://people.skolelinux.org/pere/blog/Release_0_1_1_of_free_software_archive_system_Nikita_announced.html - http://people.skolelinux.org/pere/blog/Release_0_1_1_of_free_software_archive_system_Nikita_announced.html - Sat, 10 Jun 2017 00:40:00 +0200 - <p>I am very happy to report that the -<a href="https://github.com/hiOA-ABI/nikita-noark5-core">Nikita Noark 5 -core project</a> tagged its second release today. The free software -solution is an implementation of the Norwegian archive standard Noark -5 used by government offices in Norway. These were the changes in -version 0.1.1 since version 0.1.0 (from NEWS.md): - -<ul> - - <li>Continued work on the angularjs GUI, including document upload.</li> - <li>Implemented correspondencepartPerson, correspondencepartUnit and - correspondencepartInternal</li> - <li>Applied for coverity coverage and started submitting code on - regualr basis.</li> - <li>Started fixing bugs reported by coverity</li> - <li>Corrected and completed HATEOAS links to make sure entire API is - available via URLs in _links.</li> - <li>Corrected all relation URLs to use trailing slash.</li> - <li>Add initial support for storing data in ElasticSearch.</li> - <li>Now able to receive and store uploaded files in the archive.</li> - <li>Changed JSON output for object lists to have relations in _links.</li> - <li>Improve JSON output for empty object lists.</li> - <li>Now uses correct MIME type application/vnd.noark5-v4+json.</li> - <li>Added support for docker container images.</li> - <li>Added simple API browser implemented in JavaScript/Angular.</li> - <li>Started on archive client implemented in JavaScript/Angular.</li> - <li>Started on prototype to show the public mail journal.</li> - <li>Improved performance by disabling Sprint FileWatcher.</li> - <li>Added support for 'arkivskaper', 'saksmappe' and 'journalpost'.</li> - <li>Added support for some metadata codelists.</li> - <li>Added support for Cross-origin resource sharing (CORS).</li> - <li>Changed login method from Basic Auth to JSON Web Token (RFC 7519) - style.</li> - <li>Added support for GET-ing ny-* URLs.</li> - <li>Added support for modifying entities using PUT and eTag.</li> - <li>Added support for returning XML output on request.</li> - <li>Removed support for English field and class names, limiting ourself - to the official names.</li> - <li>...</li> - -</ul> - -<p>If this sound interesting to you, please contact us on IRC (#nikita -on irc.freenode.net) or email -(<a href="https://lists.nuug.no/mailman/listinfo/nikita-noark">nikita-noark -mailing list).</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 +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Idea for storing trusted timestamps in a Noark 5 archive - http://people.skolelinux.org/pere/blog/Idea_for_storing_trusted_timestamps_in_a_Noark_5_archive.html - http://people.skolelinux.org/pere/blog/Idea_for_storing_trusted_timestamps_in_a_Noark_5_archive.html - Wed, 7 Jun 2017 21:40:00 +0200 - <p><em>This is a copy of -<a href="https://lists.nuug.no/pipermail/nikita-noark/2017-June/000297.html">an -email I posted to the nikita-noark mailing list</a>. Please follow up -there if you would like to discuss this topic. The background is that -we are making a free software archive system based on the Norwegian -<a href="https://www.arkivverket.no/forvaltning-og-utvikling/regelverk-og-standarder/noark-standarden">Noark -5 standard</a> for government archives.</em></p> - -<p>I've been wondering a bit lately how trusted timestamps could be -stored in Noark 5. -<a href="https://en.wikipedia.org/wiki/Trusted_timestamping">Trusted -timestamps</a> can be used to verify that some information -(document/file/checksum/metadata) have not been changed since a -specific time in the past. This is useful to verify the integrity of -the documents in the archive.</p> - -<p>Then it occured to me, perhaps the trusted timestamps could be -stored as dokument variants (ie dokumentobjekt referered to from -dokumentbeskrivelse) with the filename set to the hash it is -stamping?</p> - -<p>Given a "dokumentbeskrivelse" with an associated "dokumentobjekt", -a new dokumentobjekt is associated with "dokumentbeskrivelse" with the -same attributes as the stamped dokumentobjekt except these -attributes:</p> - -<ul> - -<li>format -> "RFC3161" -<li>mimeType -> "application/timestamp-reply" -<li>formatDetaljer -> "&lt;source URL for timestamp service&gt;" -<li>filenavn -> "&lt;sjekksum&gt;.tsr" - -</ul> - -<p>This assume a service following -<a href="https://tools.ietf.org/html/rfc3161">IETF RFC 3161</a> is -used, which specifiy the given MIME type for replies and the .tsr file -ending for the content of such trusted timestamp. As far as I can -tell from the Noark 5 specifications, it is OK to have several -variants/renderings of a dokument attached to a given -dokumentbeskrivelse objekt. It might be stretching it a bit to make -some of these variants represent crypto-signatures useful for -verifying the document integrity instead of representing the dokument -itself.</p> - -<p>Using the source of the service in formatDetaljer allow several -timestamping services to be used. This is useful to spread the risk -of key compromise over several organisations. It would only be a -problem to trust the timestamps if all of the organisations are -compromised.</p> - -<p>The following oneliner on Linux can be used to generate the tsr -file. $input is the path to the file to checksum, and $sha256 is the -SHA-256 checksum of the file (ie the "<sjekksum>.tsr" value mentioned -above).</p> + What is the most supported MIME type in Debian in 2018? + http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_in_2018_.html + http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_in_2018_.html + Mon, 9 Jul 2018 08:05:00 +0200 + <p>Five years ago, +<a href="http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_.html">I +measured what the most supported MIME type in Debian was</a>, by +analysing the desktop files in all packages in the archive. Since +then, the DEP-11 AppStream system has been put into production, making +the task a lot easier. This made me want to repeat the measurement, +to see how much things changed. Here are the new numbers, for +unstable only this time: + +<p><strong>Debian Unstable:</strong></p> + +<pre> + count MIME type + ----- ----------------------- + 56 image/jpeg + 55 image/png + 49 image/tiff + 48 image/gif + 39 image/bmp + 38 text/plain + 37 audio/mpeg + 34 application/ogg + 33 audio/x-flac + 32 audio/x-mp3 + 30 audio/x-wav + 30 audio/x-vorbis+ogg + 29 image/x-portable-pixmap + 27 inode/directory + 27 image/x-portable-bitmap + 27 audio/x-mpeg + 26 application/x-ogg + 25 audio/x-mpegurl + 25 audio/ogg + 24 text/html +</pre> + +<p>The list was created like this using a sid chroot: "cat +/var/lib/apt/lists/*sid*_dep11_Components-amd64.yml.gz| zcat | awk '/^ +- \S+\/\S+$/ {print $2 }' | sort | uniq -c | sort -nr | head -20"</p> + +<p>It is interesting to see how image formats have passed text/plain +as the most announced supported MIME type. These days, thanks to the +AppStream system, if you run into a file format you do not know, and +want to figure out which packages support the format, you can find the +MIME type of the file using "file --mime &lt;filename&gt;", and then +look up all packages announcing support for this format in their +AppStream metadata (XML or .desktop file) using "appstreamcli +what-provides mimetype &lt;mime-type&gt;. For example if you, like +me, want to know which packages support inode/directory, you can get a +list like this:</p> <p><blockquote><pre> -openssl ts -query -data "$inputfile" -cert -sha256 -no_nonce \ - | curl -s -H "Content-Type: application/timestamp-query" \ - --data-binary "@-" http://zeitstempel.dfn.de > $sha256.tsr +% 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>To verify the timestamp, you first need to download the public key -of the trusted timestamp service, for example using this command:</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> -wget -O ca-cert.txt \ - https://pki.pca.dfn.de/global-services-ca/pub/cacert/chain.txt +% appstreamcli what-provides mimetype application/vnd.sketchup.skp +Could not find component providing 'mimetype::application/vnd.sketchup.skp'. +% </pre></blockquote></p> -<p>Note, the public key should be stored alongside the timestamps in -the archive to make sure it is also available 100 years from now. It -is probably a good idea to standardise how and were to store such -public keys, to make it easier to find for those trying to verify -documents 100 or 1000 years from now. :)</p> - -<p>The verification itself is a simple openssl command:</p> +<p>Yesterday I used it to figure out which packages support the STL 3D +format:</p> <p><blockquote><pre> -openssl ts -verify -data $inputfile -in $sha256.tsr \ - -CAfile ca-cert.txt -text +% appstreamcli what-provides mimetype application/sla|grep Package +Package: cura +Package: meshlab +Package: printrun +% </pre></blockquote></p> -<p>Is there any reason this approach would not work? Is it somehow against -the Noark 5 specification?</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 +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Når nynorskoversettelsen svikter til eksamen... - http://people.skolelinux.org/pere/blog/N_r_nynorskoversettelsen_svikter_til_eksamen___.html - http://people.skolelinux.org/pere/blog/N_r_nynorskoversettelsen_svikter_til_eksamen___.html - Sat, 3 Jun 2017 08:20:00 +0200 - <p><a href="http://www.aftenposten.no/norge/Krever-at-elever-ma-fa-annullert-eksamen-etter-rot-med-oppgavetekster-622459b.html">Aftenposten -melder i dag</a> om feil i eksamensoppgavene for eksamen i politikk og -menneskerettigheter, der teksten i bokmåls og nynorskutgaven ikke var -like. Oppgaveteksten er gjengitt i artikkelen, og jeg ble nysgjerring -på om den fri oversetterløsningen -<a href="https://www.apertium.org/">Apertium</a> ville gjort en bedre -jobb enn Utdanningsdirektoratet. Det kan se slik ut.</p> - -<p>Her er bokmålsoppgaven fra eksamenen:</p> - -<blockquote> -<p>Drøft utfordringene knyttet til nasjonalstatenes og andre aktørers -rolle og muligheter til å håndtere internasjonale utfordringer, som -for eksempel flykningekrisen.</p> - -<p>Vedlegge er eksempler på tekster som kan gi relevante perspektiver -på temaet:</p> -<ol> -<li>Flykningeregnskapet 2016, UNHCR og IDMC -<li>«Grenseløst Europa for fall» A-Magasinet, 26. november 2015 -</ol> - -</blockquote> - -<p>Dette oversetter Apertium slik:</p> - -<blockquote> -<p>Drøft utfordringane knytte til nasjonalstatane sine og rolla til -andre aktørar og høve til å handtera internasjonale utfordringar, som -til dømes *flykningekrisen.</p> - -<p>Vedleggja er døme på tekster som kan gje relevante perspektiv på -temaet:</p> - -<ol> -<li>*Flykningeregnskapet 2016, *UNHCR og *IDMC</li> -<li>«*Grenseløst Europa for fall» A-Magasinet, 26. november 2015</li> -</ol> - -</blockquote> - -<p>Ord som ikke ble forstått er markert med stjerne (*), og trenger -ekstra språksjekk. Men ingen ord er forsvunnet, slik det var i -oppgaven elevene fikk presentert på eksamen. Jeg mistenker dog at -"andre aktørers rolle og muligheter til ..." burde vært oversatt til -"rolla til andre aktørar og deira høve til ..." eller noe slikt, men -det er kanskje flisespikking. Det understreker vel bare at det alltid -trengs korrekturlesning etter automatisk oversettelse.</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 +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Epost inn som arkivformat i Riksarkivarens forskrift? - http://people.skolelinux.org/pere/blog/Epost_inn_som_arkivformat_i_Riksarkivarens_forskrift_.html - http://people.skolelinux.org/pere/blog/Epost_inn_som_arkivformat_i_Riksarkivarens_forskrift_.html - Thu, 27 Apr 2017 11:30:00 +0200 - <p>I disse dager, med frist 1. mai, har Riksarkivaren ute en høring på -sin forskrift. Som en kan se er det ikke mye tid igjen før fristen -som går ut på søndag. Denne forskriften er det som lister opp hvilke -formater det er greit å arkivere i -<a href="http://www.arkivverket.no/arkivverket/Offentleg-forvalting/Noark/Noark-5">Noark -5-løsninger</a> i Norge.</p> - -<p>Jeg fant høringsdokumentene hos -<a href="https://www.arkivrad.no/aktuelt/riksarkivarens-forskrift-pa-horing">Norsk -Arkivråd</a> etter å ha blitt tipset på epostlisten til -<a href="https://github.com/hiOA-ABI/nikita-noark5-core">fri -programvareprosjektet Nikita Noark5-Core</a>, som lager et Noark 5 -Tjenestegresesnitt. Jeg er involvert i Nikita-prosjektet og takket -være min interesse for tjenestegrensesnittsprosjektet har jeg lest en -god del Noark 5-relaterte dokumenter, og til min overraskelse oppdaget -at standard epost ikke er på listen over godkjente formater som kan -arkiveres. Høringen med frist søndag er en glimrende mulighet til å -forsøke å gjøre noe med det. Jeg holder på med -<a href="https://github.com/petterreinholdtsen/noark5-tester/blob/master/docs/hoering-arkivforskrift.tex">egen -høringsuttalelse</a>, og lurer på om andre er interessert i å støtte -forslaget om å tillate arkivering av epost som epost i arkivet.</p> - -<p>Er du igang med å skrive egen høringsuttalelse allerede? I så fall -kan du jo vurdere å ta med en formulering om epost-lagring. Jeg tror -ikke det trengs så mye. Her et kort forslag til tekst:</p> - -<p><blockquote> - - <p>Viser til høring sendt ut 2017-02-17 (Riksarkivarens referanse - 2016/9840 HELHJO), og tillater oss å sende inn noen innspill om - revisjon av Forskrift om utfyllende tekniske og arkivfaglige - bestemmelser om behandling av offentlige arkiver (Riksarkivarens - forskrift).</p> - - <p>Svært mye av vår kommuikasjon foregår i dag på e-post.  Vi - foreslår derfor at Internett-e-post, slik det er beskrevet i IETF - RFC 5322, - <a href="https://tools.ietf.org/html/rfc5322">https://tools.ietf.org/html/rfc5322</a>. bør - inn som godkjent dokumentformat.  Vi foreslår at forskriftens - oversikt over godkjente dokumentformater ved innlevering i § 5-16 - endres til å ta med Internett-e-post.</p> - -</blockquote></p> - -<p>Som del av arbeidet med tjenestegrensesnitt har vi testet hvordan -epost kan lagres i en Noark 5-struktur, og holder på å skrive et -forslag om hvordan dette kan gjøres som vil bli sendt over til -arkivverket så snart det er ferdig. De som er interesserte kan -<a href="https://github.com/petterreinholdtsen/noark5-tester/blob/master/docs/epostlagring.md">følge -fremdriften på web</a>.</p> - -<p>Oppdatering 2017-04-28: I dag ble høringuttalelsen jeg skrev - <a href="https://www.nuug.no/news/NUUGs_h_ringuttalelse_til_Riksarkivarens_forskrift.shtml">sendt - inn av foreningen NUUG</a>.</p> + 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> - Offentlig elektronisk postjournal blokkerer tilgang for utvalgte webklienter - http://people.skolelinux.org/pere/blog/Offentlig_elektronisk_postjournal_blokkerer_tilgang_for_utvalgte_webklienter.html - http://people.skolelinux.org/pere/blog/Offentlig_elektronisk_postjournal_blokkerer_tilgang_for_utvalgte_webklienter.html - Thu, 20 Apr 2017 13:00:00 +0200 - <p>Jeg oppdaget i dag at <a href="https://www.oep.no/">nettstedet som -publiserer offentlige postjournaler fra statlige etater</a>, OEP, har -begynt å blokkerer enkelte typer webklienter fra å få tilgang. Vet -ikke hvor mange det gjelder, men det gjelder i hvert fall libwww-perl -og curl. For å teste selv, kjør følgende:</p> - -<blockquote><pre> -% curl -v -s https://www.oep.no/pub/report.xhtml?reportId=3 2>&1 |grep '< HTTP' -< HTTP/1.1 404 Not Found -% curl -v -s --header 'User-Agent:Opera/12.0' https://www.oep.no/pub/report.xhtml?reportId=3 2>&1 |grep '< HTTP' -< HTTP/1.1 200 OK -% -</pre></blockquote> - -<p>Her kan en se at tjenesten gir «404 Not Found» for curl i -standardoppsettet, mens den gir «200 OK» hvis curl hevder å være Opera -versjon 12.0. Offentlig elektronisk postjournal startet blokkeringen -2017-03-02.</p> - -<p>Blokkeringen vil gjøre det litt vanskeligere å maskinelt hente -informasjon fra oep.no. Kan blokkeringen være gjort for å hindre -automatisert innsamling av informasjon fra OEP, slik Pressens -Offentlighetsutvalg gjorde for å dokumentere hvordan departementene -hindrer innsyn i -<a href="http://presse.no/dette-mener-np/undergraver-offentlighetsloven/">rapporten -«Slik hindrer departementer innsyn» som ble publiserte i januar -2017</a>. Det virker usannsynlig, da det jo er trivielt å bytte -User-Agent til noe nytt.</p> - -<p>Finnes det juridisk grunnlag for det offentlige å diskriminere -webklienter slik det gjøres her? Der tilgang gis eller ikke alt etter -hva klienten sier at den heter? Da OEP eies av DIFI og driftes av -Basefarm, finnes det kanskje noen dokumenter sendt mellom disse to -aktørene man kan be om innsyn i for å forstå hva som har skjedd. Men -<a href="https://www.oep.no/search/result.html?period=dateRange&fromDate=01.01.2016&toDate=01.04.2017&dateType=documentDate&caseDescription=&descType=both&caseNumber=&documentNumber=&sender=basefarm&senderType=both&documentType=all&legalAuthority=&archiveCode=&list2=196&searchType=advanced&Search=Search+in+records">postjournalen -til DIFI viser kun to dokumenter</a> det siste året mellom DIFI og -Basefarm. -<a href="https://www.mimesbronn.no/request/blokkering_av_tilgang_til_oep_fo">Mimes brønn neste</a>, -tenker jeg.</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 +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>