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  13  <h1>
  14      <a href="https://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  15
  16  </h1>
  17
  18 </div>
  19
  20
  21
  22     <div class="entry">
  23       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Time_to_translate_the_Bullseye_edition_of_the_Debian_Administrator_s_Handbook.html">Time to translate the Bullseye edition of the Debian Administrator's Handbook</a></div>
  24       <div class="date">12th September 2022</div>
  25       <div class="body"><p align="center"><img align="center" src="http://people.skolelinux.org/pere/blog/images/2020-10-20-debian-handbook-nb-testprint.jpeg" width="60%"/></p>
  26
  27 <p>(The picture is of the previous edition.)</p>
  28
  29 <p>Almost two years after the previous Norwegian Bokmål translation of
  30 the "<a href="https://debian-handbook.info/">The Debian Administrator's
  31 Handbook</a>" was published, a new edition is finally being prepared.  The
  32 english text is updated, and it is time to start working on the
  33 translations.  Around 37 percent of the strings have been updated, one
  34 way or another, and the translations starting from a complete Debian Buster
  35 edition now need to bring their translation up from 63% to 100%.  The
  36 complete book is licensed using a Creative Commons license, and has
  37 been published in several languages over the years.  The translations
  38 are done by volunteers to bring Linux in their native tongue.  The
  39 last time I checked, it complete text was available in English,
  40 Norwegian Bokmål, German, Indonesian, Brazil Portuguese and Spanish.
  41 In addition, work has been started for Arabic (Morocco), Catalan,
  42 Chinese (Simplified), Chinese (Traditional), Croatian, Czech, Danish,
  43 Dutch, French, Greek, Italian, Japanese, Korean, Persian, Polish,
  44 Romanian, Russian, Swedish, Turkish and Vietnamese.</p>
  45
  46 <p>The translation is conducted on
  47 <a href="https://hosted.weblate.org/projects/debian-handbook/">the
  48 hosted weblate project page</a>.  Prospective translators are
  49 recommeded to subscribe to
  50 <a href="http://lists.alioth.debian.org/mailman/listinfo/debian-handbook-translators">the
  51 translators mailing list</a> and should also check out
  52 <a href="https://debian-handbook.info/contribute/">the instructions for
  53 contributors</a>.</p>
  54
  55 <p>I am one of the Norwegian Bokmål translators of this book, and we
  56 have just started.  Your contribution is most welcome.</p>
  57
  58 <p>As usual, if you use Bitcoin and want to show your support of my
  59 activities, please send Bitcoin donations to my address
  60 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
  61 </div>
  62       <div class="tags">
  63
  64
  65         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
  66
  67
  68       </div>
  69     </div>
  70     <div class="padding"></div>
  71
  72     <div class="entry">
  73       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Automatic_LinuxCNC_servo_PID_tuning_.html">Automatic LinuxCNC servo PID tuning?</a></div>
  74       <div class="date">16th July 2022</div>
  75       <div class="body"><p>While working on a CNC with servo motors controlled by the
  76 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a>
  77 <a href="https://en.wikipedia.org/wiki/PID_controller">PID
  78 controller</a>, I recently had to learn how to tune the collection of values
  79 that control such mathematical machinery that a PID controller is.  It
  80 proved to be a lot harder than I hoped, and I still have not succeeded
  81 in getting the Z PID controller to successfully defy gravity, nor X
  82 and Y to move accurately and reliably.  But while climbing up this
  83 rather steep learning curve, I discovered that some motor control
  84 systems are able to tune their PID controllers.  I got the impression
  85 from the documentation that LinuxCNC were not.  This proved to be not
  86 true</p>
  87
  88 <p>The LinuxCNC
  89 <a href="http://linuxcnc.org/docs/html/man/man9/pid.9.html">pid
  90 component</a> is the recommended PID controller to use.  It uses eight
  91 constants <tt>Pgain</tt>, <tt>Igain</tt>, <tt>Dgain</tt>,
  92 <tt>bias</tt>, <tt>FF0</tt>, <tt>FF1</tt>, <tt>FF2</tt> and
  93 <tt>FF3</tt> to calculate the output value based on current and wanted
  94 state, and all of these need to have a sensible value for the
  95 controller to behave properly.  Note, there are even more values
  96 involved, theser are just the most important ones.  In my case I need
  97 the X, Y and Z axes to follow the requested path with little error.
  98 This has proved quite a challenge for someone who have never tuned a
  99 PID controller before, but there is at least some help to be found.
 100
 101 <p>I discovered that included in LinuxCNC was this old PID component
 102 at_pid claiming to have auto tuning capabilities.  Sadly it had been
 103 neglected since 2011, and could not be used as a plug in replacement
 104 for the default pid component.  One would have to rewriting the
 105 LinuxCNC HAL setup to test at_pid.  This was rather sad, when I wanted
 106 to quickly test auto tuning to see if it did a better job than me at
 107 figuring out good P, I and D values to use.</p>
 108
 109 <p>I decided to have a look if the situation could be improved.  This
 110 involved trying to understand the code and history of the pid and
 111 at_pid components.  Apparently they had a common ancestor, as code
 112 structure, comments and variable names were quite close to each other.
 113 Sadly this was not reflected in the git history, making it hard to
 114 figure out what really happened.  My guess is that the author of
 115 <a href="https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/components/at_pid.c">at_pid.c</a>
 116 took a version of
 117 <a href="https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/components/pid.c">pid.c</a>,
 118 rewrote it to follow the structure he wished pid.c to have, then added
 119 support for auto tuning and finally got it included into the LinuxCNC
 120 repository.  The restructuring and lack of early history made it
 121 harder to figure out which part of the code were relevant to the auto
 122 tuning, and which part of the code needed to be updated to work the
 123 same way as the current pid.c implementation.  I started by trying to
 124 isolate relevant changes in pid.c, and applying them to at_pid.c.  My
 125 aim was to make sure the at_pid component could replace the pid
 126 component with a simple change in the HAL setup loadrt line, without
 127 having to "rewire" the rest of the HAL configuration.  After a few
 128 hours following this approach, I had learned quite a lot about the
 129 code structure of both components, while concluding I was heading down
 130 the wrong rabbit hole, and should get back to the surface and find a
 131 different path.</p>
 132
 133 <p>For the second attempt, I decided to throw away all the PID control
 134 related part of the original at_pid.c, and instead isolate and lift
 135 the auto tuning part of the code and inject it into a copy of pid.c.
 136 This ensured compatibility with the current pid component, while
 137 adding auto tuning as a run time option.  To make it easier to identify
 138 the relevant parts in the future, I wrapped all the auto tuning code
 139 with '#ifdef AUTO_TUNER'.  The end result behave just like the current
 140 pid component by default, as that part of the code is identical.  The
 141 <a href="https://github.com/LinuxCNC/linuxcnc/pull/1820">end result
 142 entered the LinuxCNC master branch</a> a few days ago.</p>
 143
 144 <p>To enable auto tuning, one need to set a few HAL pins in the PID
 145 component.  The most important ones are <tt>tune-effort</tt>,
 146 <tt>tune-mode</tt> and <tt>tune-start</tt>.  But lets take a step
 147 back, and see what the auto tuning code will do.  I do not know the
 148 mathematical foundation of the at_pid algorithm, but from observation
 149 I can tell that the algorithm will, when enabled, produce a square
 150 wave pattern centered around the <tt>bias</tt> value on the output pin
 151 of the PID controller.  This can be seen using the HAL Scope provided
 152 by LinuxCNC.  In my case, this is translated into voltage (+-10V) sent
 153 to the motor controller, which in turn is translated into motor speed.
 154 So at_pid will ask the motor to move the axis back and forth.  The
 155 number of cycles in the pattern is controlled by the
 156 <tt>tune-cycles</tt> pin, and the extremes of the wave pattern is
 157 controlled by the <tt>tune-effort</tt> pin.  Of course, trying to
 158 change the direction of a physical object instantly (as in going
 159 directly from a positive voltage to the equivalent negative voltage)
 160 do not change velocity instantly, and it take some time for the object
 161 to slow down and move in the opposite direction.  This result in a
 162 more smooth movement wave form, as the axis in question were vibrating
 163 back and forth.  When the axis reached the target speed in the
 164 opposing direction, the auto tuner change direction again.  After
 165 several of these changes, the average time delay between the 'peaks'
 166 and 'valleys' of this movement graph is then used to calculate
 167 proposed values for Pgain, Igain and Dgain, and insert them into the
 168 HAL model to use by the pid controller.  The auto tuned settings are
 169 not great, but htye work a lot better than the values I had been able
 170 to cook up on my own, at least for the horizontal X and Y axis.  But I
 171 had to use very small <tt>tune-effort<tt> values, as my motor
 172 controllers error out if the voltage change too quickly.  I've been
 173 less lucky with the Z axis, which is moving a heavy object up and
 174 down, and seem to confuse the algorithm.  The Z axis movement became a
 175 lot better when I introduced a <tt>bias</tt> value to counter the
 176 gravitational drag, but I will have to work a lot more on the Z axis
 177 PID values.</p>
 178
 179 <p>Armed with this knowledge, it is time to look at how to do the
 180 tuning.  Lets say the HAL configuration in question load the PID
 181 component for X, Y and Z like this:</p>
 182
 183 <blockquote><pre>
 184 loadrt pid names=pid.x,pid.y,pid.z
 185 </pre></blockquote>
 186
 187 <p>Armed with the new and improved at_pid component, the new line will
 188 look like this:</p>
 189
 190 <blockquote><pre>
 191 loadrt at_pid names=pid.x,pid.y,pid.z
 192 </pre></blockquote>
 193
 194 <p>The rest of the HAL setup can stay the same.  This work because the
 195 components are referenced by name.  If the component had used count=3
 196 instead, all use of pid.# had to be changed to at_pid.#.</p>
 197
 198 <p>To start tuning the X axis, move the axis to the middle of its
 199 range, to make sure it do not hit anything when it start moving back
 200 and forth.  Next, set the <tt>tune-effort</tt> to a low number in the
 201 output range.  I used 0.1 as my initial value.  Next, assign 1 to the
 202 <tt>tune-mode</tt> value. Note, this will disable the pid controlling
 203 part and feed 0 to the output pin, which in my case initially caused a
 204 lot of drift.  In my case it proved to be a good idea with X and Y to
 205 tune the motor driver to make sure 0 voltage stopped the motor
 206 rotation.  On the other hand, for the Z axis this proved to be a bad
 207 idea, so it will depend on your setup.  It might help to set the
 208 <tt>bias</tt> value to a output value that reduce or eliminate the
 209 axis drift.  Finally, after setting <tt>tune-mode</tt>, set
 210 <tt>tune-start</tt> to 1 to activate the auto tuning.  If all go well,
 211 your axis will vibrate for a few seconds and when it is done, new
 212 values for Pgain, Igain and Dgain will be active.  To test them,
 213 change <tt>tune-mode</tt> back to 0.  Note that this might cause the
 214 machine to suddenly jerk as it bring the axis back to its commanded
 215 position, which it might have drifted away from during tuning.  To
 216 summarize with some halcmd lines:</p>
 217
 218 <blockquote><pre>
 219 setp pid.x.tune-effort 0.1
 220 setp pid.x.tune-mode 1
 221 setp pid.x.tune-start 1
 222 # wait for the tuning to complete
 223 setp pid.x.tune-mode 0
 224 </pre></blockquote>
 225
 226 <p>After doing this task quite a few times while trying to figure out
 227 how to properly tune the PID controllers on the machine in, I decided
 228 to figure out if this process could be automated, and wrote a script
 229 to do the entire tuning process from power on.  The end result will
 230 ensure the machine is powered on and ready to run, home all axis if it
 231 is not already done, check that the extra tuning pins are available,
 232 move the axis to its mid point, run the auto tuning and re-enable the
 233 pid controller when it is done.  It can be run several times.  Check
 234 out the
 235 <a href="https://github.com/SebKuzminsky/MazakVQC1540/blob/bon-dev/scripts/run-auto-pid-tuner">run-auto-pid-tuner</a>
 236 script on github if you want to learn how it is done.</p>
 237
 238 <p>My hope is that this little adventure can inspire someone who know
 239 more about motor PID controller tuning can implement even better
 240 algorithms for automatic PID tuning in LinuxCNC, making life easier
 241 for both me and all the others that want to use LinuxCNC but lack the
 242 in depth knowledge needed to tune PID controllers well.</p>
 243
 244 <p>As usual, if you use Bitcoin and want to show your support of my
 245 activities, please send Bitcoin donations to my address
 246 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 247 </div>
 248       <div class="tags">
 249
 250
 251         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer</a>, <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 252
 253
 254       </div>
 255     </div>
 256     <div class="padding"></div>
 257
 258     <div class="entry">
 259       <div class="title"><a href="https://people.skolelinux.org/pere/blog/My_free_software_activity_of_late__2022_.html">My free software activity of late (2022)</a></div>
 260       <div class="date">20th June 2022</div>
 261       <div class="body"><p>I guess it is time to bring some light on the various free software
 262 and open culture activities and projects I have worked on or been
 263 involved in the last year and a half.</p>
 264
 265 <p>First, lets mention the book
 266 <a href="http://www.hungry.com/~pere/publisher/">releases I managed to
 267 publish</a>.  The Cory Doctorow book "Hvordan knuse
 268 overvåkningskapitalismen" argue that it is not the magic machine
 269 learning of the big technology companies that causes the surveillance
 270 capitalism to thrive, it is the lack of trust busting to enforce
 271 existing anti-monopoly laws.  I also published a family of
 272 dictionaries for machinists, one sorted on the English words, one
 273 sorted on the Norwegian and the last sorted on the North Sámi words.
 274 A bit on the back burner but not forgotten is the Debian
 275 Administrators Handbook, where a new edition is being worked on.  I
 276 have not spent as much time as I want to help bring it to completion,
 277 but hope I will get more spare time to look at it before the end of
 278 the year.</p>
 279
 280 <p>With my Debian had I have spent time on several projects, both
 281 updating existing packages, helping to bring in new packages and
 282 working with upstream projects to try to get them ready to go into
 283 Debian.  The list is rather long, and I will only mention my own
 284 isenkram, openmotor, vlc bittorrent plugin, xprintidle, norwegian
 285 letter style for latex, bs1770gain, and recordmydesktop.  In addition
 286 to these I have sponsored several packages into Debian, like audmes.</p>
 287
 288 <p>The last year I have looked at several infrastructure projects for
 289 collecting meter data and video surveillance recordings.  This include
 290 several ONVIF related tools like onvifviewer and zoneminder as well as
 291 rtl-433, wmbusmeters and rtl-wmbus.</p>
 292
 293 <p>In parallel with this I have looked at fabrication related free
 294 software solutions like pycam and LinuxCNC.  The latter recently
 295 gained improved translation support using po4a and weblate, which was
 296 a harder nut to crack that I had anticipated when I started.</p>
 297
 298 <p>Several hours have been spent translating free software to
 299 Norwegian Bokmål on the Weblate hosted service.  Do not have a
 300 complete list, but you will find my contributions in at least gnucash,
 301 minetest and po4a.</p>
 302
 303 <p>I also spent quite some time on the Norwegian archiving specification
 304 Noark 5, and its companion project Nikita implementing the API
 305 specification for Noark 5.</p>
 306
 307 <p>Recently I have been looking into free software tools to do company
 308 accounting here in Norway., which present an interesting mix between
 309 law, rules, regulations, format specifications and API interfaces.</p>
 310
 311 <p>I guess I should also mention the Norwegian community driven
 312 government interfacing projects Mimes Brønn and Fiksgatami, which have
 313 ended up in a kind of limbo while the future of the projects is being
 314 worked out.</p>
 315
 316 <p>These are just a few of the projects I have been involved it, and
 317 would like to give more visibility.  I'll stop here to avoid delaying
 318 this post.</p>
 319
 320 <p>As usual, if you use Bitcoin and want to show your support of my
 321 activities, please send Bitcoin donations to my address
 322 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 323 </div>
 324       <div class="tags">
 325
 326
 327         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 328
 329
 330       </div>
 331     </div>
 332     <div class="padding"></div>
 333
 334     <div class="entry">
 335       <div class="title"><a href="https://people.skolelinux.org/pere/blog/LinuxCNC_translators_life_just_got_a_bit_easier.html">LinuxCNC translators life just got a bit easier</a></div>
 336       <div class="date"> 3rd June 2022</div>
 337       <div class="body"><p>Back in oktober last year, when I started looking at the
 338 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a> system, I
 339 proposed to change the documentation build system make life easier for
 340 translators.  The original system consisted of independently written
 341 documentation files for each language, with no automated way to track
 342 changes done in other translations and no help for the translators to
 343 know how much was left to translated.  By using
 344 <a href="https://po4a.org/">the po4a system</a> to generate POT and PO
 345 files from the English documentation, this can be improved.  A small
 346 team of LinuxCNC contributors got together and today our labour
 347 finally payed off.  Since a few hours ago, it is now possible to
 348 translate <a href="https://hosted.weblate.org/projects/linuxcnc/">the
 349 LinuxCNC documentation on Weblate</a>, alongside the program itself.</p>
 350
 351 <p>The effort to migrate the documentation to use po4a has been both
 352 slow and frustrating.  I am very happy we finally made it.</p>
 353
 354 <p>As usual, if you use Bitcoin and want to show your support of my
 355 activities, please send Bitcoin donations to my address
 356 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 357 </div>
 358       <div class="tags">
 359
 360
 361         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer</a>, <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 362
 363
 364       </div>
 365     </div>
 366     <div class="padding"></div>
 367
 368     <div class="entry">
 369       <div class="title"><a href="https://people.skolelinux.org/pere/blog/geteltorito_make_CD_firmware_upgrades_a_breeze.html">geteltorito make CD firmware upgrades a breeze</a></div>
 370       <div class="date">20th April 2022</div>
 371       <div class="body"><p>Recently I wanted to upgrade the firmware of my thinkpad, and
 372 located the firmware download page from Lenovo (which annoyingly do
 373 not allow access via Tor, forcing me to hand them more personal
 374 information that I would like).  The
 375 <a href="https://support.lenovo.com/no/en/search?query=thinkpad firmware bios upgrade iso&SearchType=Customer search&searchLocation=Masthead">download
 376 from Lenovo</a> is a bootable ISO image, which is a bit of a problem
 377 when all I got available is a USB memory stick.  I tried booting the
 378 ISO as a USB stick, but this did not work.  But genisoimage came to
 379 the rescue.</p>
 380
 381 <P>The geteltorito program in
 382 <a href="http://tracker.debian.org/cdrkit">the genisoimage binary
 383 package</a> is able to convert the bootable ISO image to a bootable
 384 USB stick using a simple command line recipe, which I then can write
 385 to the most recently inserted USB stick:</p>
 386
 387 <blockquote><pre>
 388 geteltorito -o usbstick.img lenovo-firmware.iso
 389 sudo dd bs=10M if=usbstick.img of=$(ls -tr /dev/sd?|tail -1)
 390 </pre></blockquote>
 391
 392 <p>This USB stick booted the firmware upgrader just fine, and in a few
 393 minutes my machine had the latest and greatest BIOS firmware in place.</p>
 394 </div>
 395       <div class="tags">
 396
 397
 398         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 399
 400
 401       </div>
 402     </div>
 403     <div class="padding"></div>
 404
 405     <div class="entry">
 406       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Playing_and_encoding_AV1_in_Debian_Bullseye.html">Playing and encoding AV1 in Debian Bullseye</a></div>
 407       <div class="date">16th April 2022</div>
 408       <div class="body"><p>Inspired by the recent news of
 409 <a href="https://slashdot.org/story/22/04/03/2039219/intel-beats-amd-and-nvidia-with-arc-gpus-full-av1-support">AV1
 410 hardware encoding support from Intel</a>, I decided to look into
 411 the state of AV1 on Linux today.  AV1 is a
 412 <a href="https://web.archive.org/web/20160618103850/http://www.digistan.org/open-standard:definition">free
 413 and open standard</a> as defined by Digistan without any royalty
 414 payment requirement, unlike its much used competitor encoding
 415 H.264.  While looking, I came across an 5 year
 416 <a href="https://askubuntu.com/questions/1061908/how-to-encode-and-playback-video-with-the-av1-codec-on-bionic-beaver-18-04">old
 417 question on askubuntu.com</a> which in turn inspired me to check out
 418 how things are in Debian Stable regarding AV1.  The test file listed
 419 in the question (askubuntu_test_aom.mp4) did not exist any more, so I
 420 tracked down a different set of test files on
 421 <a href="https://av1.webmfiles.org/">av1.webmfiles.org</a> to test them
 422 with the various video tools I had installed on my machine.  I was
 423 happy to discover that AV1 decoding and playback worked with almost
 424 every tool I tested:
 425
 426 <table align="center">
 427 <tr><td>mediainfo</td>       <td>ok</td></tr>
 428 <tr><td>dragonplayer</td>    <td>ok</td></tr>
 429 <tr><td>ffmpeg / ffplay</td> <td>ok</td></tr>
 430 <tr><td>gnome-mplayer</td>   <td>fail</td></tr>
 431 <tr><td>mplayer</td>         <td>ok</td></tr>
 432 <tr><td>mpv</td>             <td>ok</td></tr>
 433 <tr><td>parole</td>          <td>ok</td></tr>
 434 <tr><td>vlc</td>             <td>ok</td></tr>
 435 <tr><td>firefox</td>         <td>ok</td></tr>
 436 <tr><td>chromium</td>        <td>ok</td></tr>
 437 </table>
 438
 439 <p>AV1 encoding is available in Debian Stable from the aom-tools
 440 version 1.0.0.errata1-3 package, using the aomenc tool.  The encoding
 441 using the package in Debian Stable is quite slow, with the frame rate
 442 for my 10 second test video at around 0.25 fps.  My 10 second video
 443 test took 16 minutes and 11 seconds on my test machine.</p>
 444
 445 <p>I tested by first running ffmpeg and then aomenc using the recipe
 446 provided by the askubuntu recipe above.  I had to remove the
 447 '--row-mt=1' option, as it was not supported in my 1.0.0 version.  The
 448 encoding only used a single thread, according to <tt>top</tt>.</p>
 449
 450 <blockquote><pre>
 451 ffmpeg -i some-old-video.ogv -t 10 -pix_fmt yuv420p video.y4m
 452 aomenc --fps=24/1 -u 0 --codec=av1 --target-bitrate=1000 \
 453   --lag-in-frames=25 --auto-alt-ref=1 -t 24 --cpu-used=8 \
 454   --tile-columns=2 --tile-rows=2 -o output.webm video.y4m
 455 </pre></blockquote>
 456
 457 <p>As version 1.0.0 currently have several
 458 <a href="https://security-tracker.debian.org/tracker/source-package/aom">unsolved
 459 security issues in Debian Stable</a>, and to see if the recent
 460 backport <a href="https://tracker.debian.org/pkg/aom">provided in
 461 Debian</a> is any quicker, I ran <tt>apt -t bullseye-backports install
 462 aom-tools</tt> to fetch the backported version and re-encoded the
 463 video using the latest version.  This time the '--row-mt=1' option
 464 worked, and the encoding was done in 46 seconds with a frame rate of
 465 around 5.22 fps.  This time it seem to be using all my four cores to
 466 encode.  Encoding speed is still too low for streaming and real time,
 467 which would require frame rates above 25 fps, but might be good enough
 468 for offline encoding.</p>
 469
 470 <p>I am very happy to see AV1 playback working so well with the
 471 default tools in Debian Stable.  I hope the encoding situation improve
 472 too, allowing even a slow old computer like my 10 year old laptop to
 473 be used for encoding.</p>
 474
 475 <p>As usual, if you use Bitcoin and want to show your support of my
 476 activities, please send Bitcoin donations to my address
 477 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 478 </div>
 479       <div class="tags">
 480
 481
 482         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/standard">standard</a>, <a href="https://people.skolelinux.org/pere/blog/tags/video">video</a>.
 483
 484
 485       </div>
 486     </div>
 487     <div class="padding"></div>
 488
 489     <div class="entry">
 490       <div class="title"><a href="https://people.skolelinux.org/pere/blog/F__en_slutt_p__Digitale_utslipp.html">Få en slutt på Digitale utslipp</a></div>
 491       <div class="date">14th March 2022</div>
 492       <div class="body"><p>På onsdag sendte jeg følgende epost til Utdanningsetaten i Oslo
 493 kommune (UDE).  Fikk beskjed om at min henvendelse har saksnummer
 494 22/7559-1 i den
 495 <a href="https://www.oslo.kommune.no/etater-foretak-og-ombud/utdanningsetaten/postjournal-utdanningsetaten/">offentlige
 496 postjournalen til UDE</a>.  Jeg er spent på hva slags respons jeg får.
 497 Mistenker jo de fleste som sprer sine nettsideleseres
 498 personopplysninger til utlandet ikke har tenkt så nøye igjennom hva de
 499 gjør, og at det er håp om at de tenker seg litt nøyere om hvis de blir
 500 klar over problemstillingen.  Vet du noen som burde få tilsvarede
 501 beskjed og spørsmål?  Kanskje du kan sende dem en epost.  Hvis alle
 502 bidrar blir det kanskje litt bedre.</p>
 503
 504 <blockquote>
 505 <p>To: postmottak (at) osloskolen.no
 506 <br>Subject: Digitale utslipp fra osloskolens nettsider</p>
 507
 508 <p>Hei.</p>
 509
 510 <p>Jeg ser at osloskolens nettsider har digitale utslipp av
 511 personopplysninger til Google, Facebook og andre, blant annet omtalt
 512 på &lt;URL: <a href="https://aktuelt.osloskolen.no/personvernerklaring-for-osloskolen/informasjonskapsler/">https://aktuelt.osloskolen.no/personvernerklaring-for-osloskolen/informasjonskapsler/</a>
 513 >.</p>
 514
 515 <p>&lt;URL: <a href="https://webbkoll.dataskydd.net/">https://webbkoll.dataskydd.net/</a> > kan være et nyttig verktøy for å holde øye med utslippsomfanget på ulike sider.</p>
 516
 517 <p>Kanskje det er en ide å gjøre noe med det, jamfør &lt;URL: <a href="https://www.digi.no/artikler/debatt-det-enkleste-tiltaket-er-a-skru-av-google-analytics/517378">https://www.digi.no/artikler/debatt-det-enkleste-tiltaket-er-a-skru-av-google-analytics/517378</a> >?</p>
 518
 519 <p>Et alternativ til Google Analytics kan være en lokalt installert
 520 utgave av &lt;URL:
 521 <a href="https://matomo.org/">https://matomo.org/</a> >.  Den og flere
 522 andre alternativer kan finnes via
 523 &lt;URL: <a href="https://www.digi.no/artikler/sverige-vil-skrote-amerikansk-skytjeneste-her-er-alternativene/516223?key=5QsV0wRG">https://www.digi.no/artikler/sverige-vil-skrote-amerikansk-skytjeneste-her-er-alternativene/516223?key=5QsV0wRG</a> >
 524 på bakgrunn av at svenske myndigheter har innsett at dagens praksis
 525 nok er både lite lur og ulovlig.  Der henger Norge litt etter, men
 526 osloskolen har her mulighet til å være litt i forkant. :)</p>
 527
 528 <p>Fint om dere kan gi beskjed hvilket saksnummer denne henvendelsen får i
 529 offentlig postjournal når den er mottatt.</p>
 530
 531 </blockquote>
 532
 533 </p>Flere og flere innser at slik spredning av personopplysninger er
 534 ugreit.  Det har pågått i mange år.  Ser jeg blogget
 535 <a href="https://people.skolelinux.org/pere/blog/Det_er_jo_makta_som_er_mest_s_rbar_ved_massiv_overv_kning_av_Internett.html">første
 536 gang om Google Analytics i 2013</a> og
 537 <a href="https://people.skolelinux.org/pere/blog/Snurpenot_overv_kning_av_sensitiv_personinformasjon.html">analyserte
 538 omfanget i 2015</a>, men det er et langt lerret å bleke.</p>
 539
 540 <p>Som vanlig, hvis du bruker Bitcoin og ønsker å vise din støtte til
 541 det jeg driver med, setter jeg pris på om du sender Bitcoin-donasjoner
 542 til min adresse
 543 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.
 544 Merk, betaling med bitcoin er ikke anonymt. :)</p>
 545 </div>
 546       <div class="tags">
 547
 548
 549         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="https://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="https://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 550
 551
 552       </div>
 553     </div>
 554     <div class="padding"></div>
 555
 556     <div class="entry">
 557       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Publish_Hargassner_wood_chip_boiler_state_to_MQTT.html">Publish Hargassner wood chip boiler state to MQTT</a></div>
 558       <div class="date">12th March 2022</div>
 559       <div class="body"><p>Recently I had a look at a
 560 <a href="https://www.hargassner.at/">Hargassner</a>
 561 <a href="https://www.hargassner.at/en/products/wood-chip-boiler.html">wood
 562 chip boiler</a>, and what kind of free software can be used to monitor
 563 and control it.  The boiler can be connected to some cloud service via
 564 what the producer call an Internet Gateway, which seem to be a
 565 computer connecting to the boiler and passing the information gathered
 566 to the cloud.  I discovered the boiler controller got an IP address on
 567 the local network and listen on TCP port 23 to provide status
 568 information as a text line of numbers.  It also provide a HTTP server
 569 listening on port 80, but I have not yet figured out what it can do
 570 beside return an error code.</p>
 571
 572 <p>If I am to believe various free software implementations talking to
 573 such boiler, the interpretation of the line of numbers differ between
 574 type of boiler and software version on the boiler.  By comparing the
 575 list of numbers on the front panel of the boiler with the numbers
 576 returned via TCP, I have been able to figure out several of the
 577 numbers, but there are a lot left to understand.  I've located several
 578 temperature measurements and hours running values, as well as oxygen
 579 measurements and counters.</p>
 580
 581 I decided to write a simple parser in Python for the values I figured
 582 out so far, and a simple MQTT injector publishing both the interpreted
 583 and the unknown values on a MQTT bus to make collecting and graphing
 584 simpler.  The end result is available from the
 585 <a href="https://gitlab.com/petterreinholdtsen/hargassner2mqtt">hargassner2mqtt
 586 project page</a> on gitlab.  I very much welcome patches extending the
 587 parser to understand more values, boiler types and software versions.
 588 I do not really expect very few free software developers got their
 589 hands on such unit to experiment, but it would be fun if others too find
 590 this project useful.</p>
 591
 592 <p>As usual, if you use Bitcoin and want to show your support of my
 593 activities, please send Bitcoin donations to my address
 594 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 595 </div>
 596       <div class="tags">
 597
 598
 599         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 600
 601
 602       </div>
 603     </div>
 604     <div class="padding"></div>
 605
 606     <div class="entry">
 607       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Run_your_industrial_metal_working_machine_using_Debian_.html">Run your industrial metal working machine using Debian?</a></div>
 608       <div class="date"> 2nd March 2022</div>
 609       <div class="body"><p>After many months of hard work by the good people involved in
 610 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a>, the
 611 system was accepted Sunday
 612 <a href="https://tracker.debian.org/pkg/linuxcnc">into Debian</a>.
 613 Once it was available from Debian, I was surprised to discover from
 614 <a href="https://qa.debian.org/popcon.php?package=linuxcnc">its
 615 popularity-contest numbers</a> that people have been reporting its use
 616 since 2012.  <a href="http://linuxcnc.org/">Its project site</a> might
 617 be a good place to check out, but sadly is not working when visiting
 618 via Tor.</p>
 619
 620 <p>But what is LinuxCNC, you are probably wondering?  Perhaps a
 621 Wikipedia quote is in place?</p>
 622
 623 <blockquote>
 624 "LinuxCNC is a software system for numerical control of
 625 machines such as milling machines, lathes, plasma cutters, routers,
 626 cutting machines, robots and hexapods. It can control up to 9 axes or
 627 joints of a CNC machine using G-code (RS-274NGC) as input. It has
 628 several GUIs suited to specific kinds of usage (touch screen,
 629 interactive development)."
 630 </blockquote>
 631
 632 <p>It can even control 3D printers.  And even though the Wikipedia
 633 page indicate that it can only work with hard real time kernel
 634 features, it can also work with the user space soft real time features
 635 provided by the Debian kernel.
 636 <a href="https://github.com/linuxcnc/linuxcnc">The source code</a> is
 637 available from Github.  The last few months I've been involved in the
 638 translation setup for the program and documentation.  Translators are
 639 most welcome to
 640 <a href="https://hosted.weblate.org/engage/linuxcnc/">join the
 641 effort</a> using Weblate.</p>
 642
 643 <p>As usual, if you use Bitcoin and want to show your support of my
 644 activities, please send Bitcoin donations to my address
 645 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 646 </div>
 647       <div class="tags">
 648
 649
 650         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer</a>, <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 651
 652
 653       </div>
 654     </div>
 655     <div class="padding"></div>
 656
 657     <div class="entry">
 658       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Updated_vlc_bittorrent_plugin_in_Debian__version_2_14_.html">Updated vlc bittorrent plugin in Debian (version 2.14)</a></div>
 659       <div class="date">14th February 2022</div>
 660       <div class="body"><p>I am very happy to report that a new version of the
 661 <a href="https://tracker.debian.org/pkg/vlc-plugin-bittorrent">VLC
 662 bittorrent plugin</a> was just uploaded into debian.  The changes
 663 since last time is mostly code clean in the download code. The package
 664 is currently in Debian unstable, but should be available in Debian
 665 testing son.  To test it, simply install it like this:</p>
 666
 667 <p><pre>
 668 apt install vlc-plugin-bittorrent
 669 </pre></p>
 670
 671 <p>After it is installed, you can try to use it to play a file
 672 downloaded live via bittorrent like this:
 673
 674 <p><pre>
 675 vlc https://archive.org/download/Glass_201703/Glass_201703_archive.torrent
 676 </pre></p>
 677
 678 <p>It can also use magnet links and local .torrent files like the ones
 679 provided by the Internet Archive.  Another example is the <a
 680 href="https://archive.org/details/LoveNest">Love Nest</a> Buster
 681 Keaton movie, where one can click on the 'Torrent' link to get going.</p>
 682
 683 <p>As usual, if you use Bitcoin and want to show your support of my
 684 activities, please send Bitcoin donations to my address
 685 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 686 </div>
 687       <div class="tags">
 688
 689
 690         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/verkidetfri">verkidetfri</a>, <a href="https://people.skolelinux.org/pere/blog/tags/video">video</a>.
 691
 692
 693       </div>
 694     </div>
 695     <div class="padding"></div>
 696
 697     <p style="text-align: right;"><a href="index.rss"><img src="https://people.skolelinux.org/pere/blog/xml.gif" alt="RSS feed" width="36" height="14" /></a></p>
 698     <div id="sidebar">
 699
 700
 701
 702 <h2>Archive</h2>
 703 <ul>
 704
 705 <li>2022
 706 <ul>
 707
 708 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/02/">February (1)</a></li>
 709
 710 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/03/">March (3)</a></li>
 711
 712 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/04/">April (2)</a></li>
 713
 714 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/06/">June (2)</a></li>
 715
 716 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/07/">July (1)</a></li>
 717
 718 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/09/">September (1)</a></li>
 719
 720 </ul></li>
 721
 722 <li>2021
 723 <ul>
 724
 725 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/01/">January (2)</a></li>
 726
 727 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/02/">February (1)</a></li>
 728
 729 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/05/">May (1)</a></li>
 730
 731 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/06/">June (1)</a></li>
 732
 733 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/07/">July (3)</a></li>
 734
 735 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/08/">August (1)</a></li>
 736
 737 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/09/">September (1)</a></li>
 738
 739 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/10/">October (1)</a></li>
 740
 741 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/12/">December (1)</a></li>
 742
 743 </ul></li>
 744
 745 <li>2020
 746 <ul>
 747
 748 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/02/">February (2)</a></li>
 749
 750 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/03/">March (2)</a></li>
 751
 752 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/04/">April (2)</a></li>
 753
 754 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/05/">May (3)</a></li>
 755
 756 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/06/">June (2)</a></li>
 757
 758 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/07/">July (1)</a></li>
 759
 760 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/09/">September (1)</a></li>
 761
 762 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/10/">October (1)</a></li>
 763
 764 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/11/">November (1)</a></li>
 765
 766 </ul></li>
 767
 768 <li>2019
 769 <ul>
 770
 771 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/01/">January (4)</a></li>
 772
 773 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/02/">February (3)</a></li>
 774
 775 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/03/">March (3)</a></li>
 776
 777 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/05/">May (2)</a></li>
 778
 779 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/06/">June (5)</a></li>
 780
 781 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/07/">July (2)</a></li>
 782
 783 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/08/">August (1)</a></li>
 784
 785 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/09/">September (1)</a></li>
 786
 787 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/11/">November (1)</a></li>
 788
 789 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/12/">December (4)</a></li>
 790
 791 </ul></li>
 792
 793 <li>2018
 794 <ul>
 795
 796 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/01/">January (1)</a></li>
 797
 798 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/02/">February (5)</a></li>
 799
 800 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/03/">March (5)</a></li>
 801
 802 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/04/">April (3)</a></li>
 803
 804 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/06/">June (2)</a></li>
 805
 806 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/07/">July (5)</a></li>
 807
 808 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/08/">August (3)</a></li>
 809
 810 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/09/">September (3)</a></li>
 811
 812 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/10/">October (5)</a></li>
 813
 814 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/11/">November (2)</a></li>
 815
 816 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/12/">December (4)</a></li>
 817
 818 </ul></li>
 819
 820 <li>2017
 821 <ul>
 822
 823 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/01/">January (4)</a></li>
 824
 825 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/02/">February (3)</a></li>
 826
 827 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/03/">March (5)</a></li>
 828
 829 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/04/">April (2)</a></li>
 830
 831 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/06/">June (5)</a></li>
 832
 833 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/07/">July (1)</a></li>
 834
 835 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/08/">August (1)</a></li>
 836
 837 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/09/">September (3)</a></li>
 838
 839 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/10/">October (5)</a></li>
 840
 841 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/11/">November (3)</a></li>
 842
 843 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/12/">December (4)</a></li>
 844
 845 </ul></li>
 846
 847 <li>2016
 848 <ul>
 849
 850 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/01/">January (3)</a></li>
 851
 852 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/02/">February (2)</a></li>
 853
 854 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/03/">March (3)</a></li>
 855
 856 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/04/">April (8)</a></li>
 857
 858 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/05/">May (8)</a></li>
 859
 860 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/06/">June (2)</a></li>
 861
 862 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/07/">July (2)</a></li>
 863
 864 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/08/">August (5)</a></li>
 865
 866 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/09/">September (2)</a></li>
 867
 868 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/10/">October (3)</a></li>
 869
 870 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/11/">November (8)</a></li>
 871
 872 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/12/">December (5)</a></li>
 873
 874 </ul></li>
 875
 876 <li>2015
 877 <ul>
 878
 879 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
 880
 881 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
 882
 883 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
 884
 885 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
 886
 887 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/05/">May (3)</a></li>
 888
 889 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/06/">June (4)</a></li>
 890
 891 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/07/">July (6)</a></li>
 892
 893 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/08/">August (2)</a></li>
 894
 895 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/09/">September (2)</a></li>
 896
 897 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/10/">October (9)</a></li>
 898
 899 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/11/">November (6)</a></li>
 900
 901 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/12/">December (3)</a></li>
 902
 903 </ul></li>
 904
 905 <li>2014
 906 <ul>
 907
 908 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
 909
 910 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
 911
 912 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
 913
 914 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
 915
 916 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
 917
 918 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
 919
 920 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
 921
 922 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
 923
 924 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
 925
 926 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
 927
 928 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
 929
 930 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
 931
 932 </ul></li>
 933
 934 <li>2013
 935 <ul>
 936
 937 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 938
 939 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 940
 941 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 942
 943 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 944
 945 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 946
 947 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 948
 949 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 950
 951 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 952
 953 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 954
 955 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 956
 957 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
 958
 959 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
 960
 961 </ul></li>
 962
 963 <li>2012
 964 <ul>
 965
 966 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
 967
 968 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
 969
 970 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
 971
 972 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
 973
 974 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
 975
 976 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
 977
 978 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
 979
 980 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
 981
 982 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
 983
 984 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
 985
 986 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
 987
 988 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
 989
 990 </ul></li>
 991
 992 <li>2011
 993 <ul>
 994
 995 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 996
 997 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 998
 999 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
1000
1001 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
1002
1003 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
1004
1005 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
1006
1007 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
1008
1009 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
1010
1011 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
1012
1013 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
1014
1015 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
1016
1017 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
1018
1019 </ul></li>
1020
1021 <li>2010
1022 <ul>
1023
1024 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
1025
1026 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
1027
1028 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
1029
1030 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
1031
1032 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
1033
1034 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
1035
1036 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
1037
1038 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
1039
1040 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
1041
1042 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
1043
1044 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
1045
1046 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
1047
1048 </ul></li>
1049
1050 <li>2009
1051 <ul>
1052
1053 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
1054
1055 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
1056
1057 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
1058
1059 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
1060
1061 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
1062
1063 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
1064
1065 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
1066
1067 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
1068
1069 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
1070
1071 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
1072
1073 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
1074
1075 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
1076
1077 </ul></li>
1078
1079 <li>2008
1080 <ul>
1081
1082 <li><a href="https://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
1083
1084 <li><a href="https://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
1085
1086 </ul></li>
1087
1088 </ul>
1089
1090
1091
1092 <h2>Tags</h2>
1093 <ul>
1094
1095  <li><a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (19)</a></li>
1096
1097  <li><a href="https://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
1098
1099  <li><a href="https://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
1100
1101  <li><a href="https://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
1102
1103  <li><a href="https://people.skolelinux.org/pere/blog/tags/betalkontant">betalkontant (9)</a></li>
1104
1105  <li><a href="https://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (12)</a></li>
1106
1107  <li><a href="https://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (17)</a></li>
1108
1109  <li><a href="https://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
1110
1111  <li><a href="https://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
1112
1113  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian">debian (182)</a></li>
1114
1115  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (159)</a></li>
1116
1117  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook (9)</a></li>
1118
1119  <li><a href="https://people.skolelinux.org/pere/blog/tags/digistan">digistan (11)</a></li>
1120
1121  <li><a href="https://people.skolelinux.org/pere/blog/tags/dld">dld (18)</a></li>
1122
1123  <li><a href="https://people.skolelinux.org/pere/blog/tags/docbook">docbook (30)</a></li>
1124
1125  <li><a href="https://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
1126
1127  <li><a href="https://people.skolelinux.org/pere/blog/tags/english">english (438)</a></li>
1128
1129  <li><a href="https://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
1130
1131  <li><a href="https://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (14)</a></li>
1132
1133  <li><a href="https://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (34)</a></li>
1134
1135  <li><a href="https://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
1136
1137  <li><a href="https://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (20)</a></li>
1138
1139  <li><a href="https://people.skolelinux.org/pere/blog/tags/h264">h264 (20)</a></li>
1140
1141  <li><a href="https://people.skolelinux.org/pere/blog/tags/intervju">intervju (43)</a></li>
1142
1143  <li><a href="https://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (16)</a></li>
1144
1145  <li><a href="https://people.skolelinux.org/pere/blog/tags/kart">kart (23)</a></li>
1146
1147  <li><a href="https://people.skolelinux.org/pere/blog/tags/kodi">kodi (4)</a></li>
1148
1149  <li><a href="https://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
1150
1151  <li><a href="https://people.skolelinux.org/pere/blog/tags/lego">lego (5)</a></li>
1152
1153  <li><a href="https://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
1154
1155  <li><a href="https://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
1156
1157  <li><a href="https://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
1158
1159  <li><a href="https://people.skolelinux.org/pere/blog/tags/madewithcc">madewithcc (3)</a></li>
1160
1161  <li><a href="https://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
1162
1163  <li><a href="https://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (42)</a></li>
1164
1165  <li><a href="https://people.skolelinux.org/pere/blog/tags/nice free software">nice free software (13)</a></li>
1166
1167  <li><a href="https://people.skolelinux.org/pere/blog/tags/noark5">noark5 (23)</a></li>
1168
1169  <li><a href="https://people.skolelinux.org/pere/blog/tags/norsk">norsk (320)</a></li>
1170
1171  <li><a href="https://people.skolelinux.org/pere/blog/tags/nuug">nuug (198)</a></li>
1172
1173  <li><a href="https://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (40)</a></li>
1174
1175  <li><a href="https://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
1176
1177  <li><a href="https://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (75)</a></li>
1178
1179  <li><a href="https://people.skolelinux.org/pere/blog/tags/personvern">personvern (114)</a></li>
1180
1181  <li><a href="https://people.skolelinux.org/pere/blog/tags/raid">raid (2)</a></li>
1182
1183  <li><a href="https://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
1184
1185  <li><a href="https://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
1186
1187  <li><a href="https://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
1188
1189  <li><a href="https://people.skolelinux.org/pere/blog/tags/robot">robot (16)</a></li>
1190
1191  <li><a href="https://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
1192
1193  <li><a href="https://people.skolelinux.org/pere/blog/tags/ruter">ruter (7)</a></li>
1194
1195  <li><a href="https://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
1196
1197  <li><a href="https://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (59)</a></li>
1198
1199  <li><a href="https://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
1200
1201  <li><a href="https://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (5)</a></li>
1202
1203  <li><a href="https://people.skolelinux.org/pere/blog/tags/standard">standard (72)</a></li>
1204
1205  <li><a href="https://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (7)</a></li>
1206
1207  <li><a href="https://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (14)</a></li>
1208
1209  <li><a href="https://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (62)</a></li>
1210
1211  <li><a href="https://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (5)</a></li>
1212
1213  <li><a href="https://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
1214
1215  <li><a href="https://people.skolelinux.org/pere/blog/tags/valg">valg (9)</a></li>
1216
1217  <li><a href="https://people.skolelinux.org/pere/blog/tags/verkidetfri">verkidetfri (20)</a></li>
1218
1219  <li><a href="https://people.skolelinux.org/pere/blog/tags/video">video (77)</a></li>
1220
1221  <li><a href="https://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
1222
1223  <li><a href="https://people.skolelinux.org/pere/blog/tags/web">web (42)</a></li>
1224
1225 </ul>
1226
1227
1228     </div>
1229     <p style="text-align: right">
1230  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
1231 </p>
1232
1233   </body>
1234 </html>