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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/ONVIF_IP_camera_management_tool_finally_in_Debian.html">ONVIF IP camera management tool finally in Debian</a></div>
  24       <div class="date">24th December 2022</div>
  25       <div class="body"><p>Merry Christmas to you all.  Here is a small gift to all those with
  26 IP cameras following the <a href="https://www.onvif.org/">ONVIF
  27 specification</a>.  There is finally a nice command line and GUI tool
  28 in Debian to manage ONVIF IP cameras.  After working with upstream for
  29 a few months and sponsoring the upload, I am very happy to report that
  30 the <a href="https://tracker.debian.org/libonvif">libonvif package</a>
  31 entered Debian Sid last night.</p>
  32
  33 <p>The package provide a C library to communicate with such cameras, a
  34 command line tool to locate and update settings of (like password) the
  35 cameras and a GUI tool to configure and control the units as well as
  36 preview the video from the camera.  Libonvif is available on Both
  37 Linux and Windows and the GUI tool uses the Qt library.  The main
  38 competitors are non-free software, while libonvif is GNU GPL licensed.
  39 I am very glad Debian users in the future can control their cameras
  40 using a free software system provided by Debian.  But the ONVIF world
  41 is full of slightly broken firmware, where the cameras pretend to
  42 follow the ONVIF specification but fail to set some configuration
  43 values or refuse to provide video to more than one recipient at the
  44 time, and the onvif project is quite young and might take a while
  45 before it completely work with your camera.  Upstream seem eager to
  46 improve the library, so handling any broken camera might be just <a
  47 href="https://github.com/sr99622/libonvif/">a bug report away</a>.</p>
  48
  49 <p>The package just cleared NEW, and need a new source only upload
  50 before it can enter testing.  This will happen in the next few
  51 days.</p>
  52
  53 <p>As usual, if you use Bitcoin and want to show your support of my
  54 activities, please send Bitcoin donations to my address
  55 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
  56 </div>
  57       <div class="tags">
  58
  59
  60         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>, <a href="https://people.skolelinux.org/pere/blog/tags/multimedia">multimedia</a>, <a href="https://people.skolelinux.org/pere/blog/tags/standard">standard</a>, <a href="https://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
  61
  62
  63       </div>
  64     </div>
  65     <div class="padding"></div>
  66
  67     <div class="entry">
  68       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Managing_and_using_ONVIF_IP_cameras_with_Linux.html">Managing and using ONVIF IP cameras with Linux</a></div>
  69       <div class="date">19th October 2022</div>
  70       <div class="body"><p>Recently I have been looking at how to control and collect data
  71 from a handful IP cameras using Linux.  I both wanted to change their
  72 settings and to make their imagery available via a free software
  73 service under my control.  Here is a summary of the tools I found.</p>
  74
  75 <p>First I had to identify the cameras and their protocols.  As far as
  76 I could tell, they were using some SOAP looking protocol and their
  77 internal web server seem to only work with Microsoft Internet Explorer
  78 with some proprietary binary plugin, which in these days of course is
  79 a security disaster and also made it impossible for me to use the
  80 camera web interface.  Luckily I discovered that the SOAP looking
  81 protocol is actually following <a href="https://www.onvif.org/">the
  82 ONVIF specification</a>, which seem to be supported by a lot of IP
  83 cameras these days.</p>
  84
  85 <p>Once the protocol was identified, I was able to find what appear to
  86 be the most popular way to configure ONVIF cameras, the free software
  87 Windows tool named
  88 <a href="https://sourceforge.net/projects/onvifdm/">ONVIF Device
  89 Manager</a>.  Lacking any other options at the time, I tried
  90 unsuccessfully to get it running using Wine, but was missing a dotnet
  91 40 library and I found no way around it to run it on Linux.</p>
  92
  93 <p>The next tool I found to configure the cameras were a non-free Linux Qt
  94 client <a href="https://www.lingodigit.com/onvif_nvcdemo.html">ONVIF
  95 Device Tool</a>.  I did not like its terms of use, so did not spend
  96 much time on it.</p>
  97
  98 <p>To collect the video and make it available in a web interface, I
  99 found the Zoneminder tool in Debian.  A recent version was able to
 100 automatically detect and configure ONVIF devices, so I could use it to
 101 set up motion detection in and collection of the camera output.  I had
 102 initial problems getting the ONVIF autodetection to work, as both
 103 Firefox and Chromium <a href="https://bugs.debian.org/1001188">refused
 104 the inter-tab communication</a> being used by the Zoneminder web
 105 pages, but managed to get konqueror to work.  Apparently the "Enhanced
 106 Tracking Protection" in Firefox cause the problem.  I ended up
 107 upgrading to the Bookworm edition of Zoneminder in the process to try
 108 to fix the issue, and believe the problem might be solved now.</p>
 109
 110 <p>In the process I came across the nice Linux GUI tool
 111 <a href="https://gitlab.com/caspermeijn/onvifviewer/">ONVIF Viewer</a>
 112 allowing me to preview the camera output and validate the login
 113 passwords required.  Sadly its author has grown tired of maintaining
 114 the software, so it might not see any future updates.  Which is sad,
 115 as the viewer is sightly unstable and the picture tend to lock up.
 116 Note, this lockup might be due to limitations in the cameras and not
 117 the viewer implementation.  I suspect the camera is only able to
 118 provide pictures to one client at the time, and the Zoneminder feed
 119 might interfere with the GUI viewer.  I have
 120 <a href="https://bugs.debian.org/1000820">asked for the tool to be
 121 included in Debian</a>.</p>
 122
 123 <p>Finally, I found what appear to be very nice Linux free software
 124 replacement for the Windows tool, named
 125 <a href="https://github.com/sr99622/libonvif/">libonvif</a>.  It
 126 provide a C library to talk to ONVIF devices as well as a command line
 127 and GUI tool using the library.  Using the GUI tool I was able to change
 128 the admin passwords and update other settings of the cameras.  I have
 129 <a href="https://bugs.debian.org/1021980">asked for the package to be
 130 included in Debian</a>.</p>
 131
 132 <p>As usual, if you use Bitcoin and want to show your support of my
 133 activities, please send Bitcoin donations to my address
 134 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 135
 136 <p><strong>Update 2022-10-20</strong>: Since my initial publication of
 137 this text, I got several suggestions for more free software Linux
 138 tools.  There is <a href="https://github.com/quatanium/python-onvif">a
 139 ONVIF python library</a> (already
 140 <a href="https://bugs.debian.org/824240">requested into Debian</a>) and
 141 <a href="https://github.com/FalkTannhaeuser/python-onvif-zeep">a python 3
 142 fork</a> using a different SOAP dependency.  There is also
 143 <a href="https://www.home-assistant.io/integrations/onvif/">support for
 144 ONVIF in Home Assistant</a>, and there is an alternative to Zoneminder
 145 called <a href="https://www.shinobi.video/">Shinobi</a>.  The latter
 146 two are not included in Debian either.  I have not tested any of these
 147 so far.</p>
 148 </div>
 149       <div class="tags">
 150
 151
 152         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>, <a href="https://people.skolelinux.org/pere/blog/tags/multimedia">multimedia</a>, <a href="https://people.skolelinux.org/pere/blog/tags/standard">standard</a>, <a href="https://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 153
 154
 155       </div>
 156     </div>
 157     <div class="padding"></div>
 158
 159     <div class="entry">
 160       <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>
 161       <div class="date">12th September 2022</div>
 162       <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>
 163
 164 <p>(The picture is of the previous edition.)</p>
 165
 166 <p>Almost two years after the previous Norwegian Bokmål translation of
 167 the "<a href="https://debian-handbook.info/">The Debian Administrator's
 168 Handbook</a>" was published, a new edition is finally being prepared.  The
 169 english text is updated, and it is time to start working on the
 170 translations.  Around 37 percent of the strings have been updated, one
 171 way or another, and the translations starting from a complete Debian Buster
 172 edition now need to bring their translation up from 63% to 100%.  The
 173 complete book is licensed using a Creative Commons license, and has
 174 been published in several languages over the years.  The translations
 175 are done by volunteers to bring Linux in their native tongue.  The
 176 last time I checked, it complete text was available in English,
 177 Norwegian Bokmål, German, Indonesian, Brazil Portuguese and Spanish.
 178 In addition, work has been started for Arabic (Morocco), Catalan,
 179 Chinese (Simplified), Chinese (Traditional), Croatian, Czech, Danish,
 180 Dutch, French, Greek, Italian, Japanese, Korean, Persian, Polish,
 181 Romanian, Russian, Swedish, Turkish and Vietnamese.</p>
 182
 183 <p>The translation is conducted on
 184 <a href="https://hosted.weblate.org/projects/debian-handbook/">the
 185 hosted weblate project page</a>.  Prospective translators are
 186 recommeded to subscribe to
 187 <a href="http://lists.alioth.debian.org/mailman/listinfo/debian-handbook-translators">the
 188 translators mailing list</a> and should also check out
 189 <a href="https://debian-handbook.info/contribute/">the instructions for
 190 contributors</a>.</p>
 191
 192 <p>I am one of the Norwegian Bokmål translators of this book, and we
 193 have just started.  Your contribution is most welcome.</p>
 194
 195 <p>As usual, if you use Bitcoin and want to show your support of my
 196 activities, please send Bitcoin donations to my address
 197 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 198 </div>
 199       <div class="tags">
 200
 201
 202         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>.
 203
 204
 205       </div>
 206     </div>
 207     <div class="padding"></div>
 208
 209     <div class="entry">
 210       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Automatic_LinuxCNC_servo_PID_tuning_.html">Automatic LinuxCNC servo PID tuning?</a></div>
 211       <div class="date">16th July 2022</div>
 212       <div class="body"><p>While working on a CNC with servo motors controlled by the
 213 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a>
 214 <a href="https://en.wikipedia.org/wiki/PID_controller">PID
 215 controller</a>, I recently had to learn how to tune the collection of values
 216 that control such mathematical machinery that a PID controller is.  It
 217 proved to be a lot harder than I hoped, and I still have not succeeded
 218 in getting the Z PID controller to successfully defy gravity, nor X
 219 and Y to move accurately and reliably.  But while climbing up this
 220 rather steep learning curve, I discovered that some motor control
 221 systems are able to tune their PID controllers.  I got the impression
 222 from the documentation that LinuxCNC were not.  This proved to be not
 223 true</p>
 224
 225 <p>The LinuxCNC
 226 <a href="http://linuxcnc.org/docs/html/man/man9/pid.9.html">pid
 227 component</a> is the recommended PID controller to use.  It uses eight
 228 constants <tt>Pgain</tt>, <tt>Igain</tt>, <tt>Dgain</tt>,
 229 <tt>bias</tt>, <tt>FF0</tt>, <tt>FF1</tt>, <tt>FF2</tt> and
 230 <tt>FF3</tt> to calculate the output value based on current and wanted
 231 state, and all of these need to have a sensible value for the
 232 controller to behave properly.  Note, there are even more values
 233 involved, theser are just the most important ones.  In my case I need
 234 the X, Y and Z axes to follow the requested path with little error.
 235 This has proved quite a challenge for someone who have never tuned a
 236 PID controller before, but there is at least some help to be found.
 237
 238 <p>I discovered that included in LinuxCNC was this old PID component
 239 at_pid claiming to have auto tuning capabilities.  Sadly it had been
 240 neglected since 2011, and could not be used as a plug in replacement
 241 for the default pid component.  One would have to rewriting the
 242 LinuxCNC HAL setup to test at_pid.  This was rather sad, when I wanted
 243 to quickly test auto tuning to see if it did a better job than me at
 244 figuring out good P, I and D values to use.</p>
 245
 246 <p>I decided to have a look if the situation could be improved.  This
 247 involved trying to understand the code and history of the pid and
 248 at_pid components.  Apparently they had a common ancestor, as code
 249 structure, comments and variable names were quite close to each other.
 250 Sadly this was not reflected in the git history, making it hard to
 251 figure out what really happened.  My guess is that the author of
 252 <a href="https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/components/at_pid.c">at_pid.c</a>
 253 took a version of
 254 <a href="https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/components/pid.c">pid.c</a>,
 255 rewrote it to follow the structure he wished pid.c to have, then added
 256 support for auto tuning and finally got it included into the LinuxCNC
 257 repository.  The restructuring and lack of early history made it
 258 harder to figure out which part of the code were relevant to the auto
 259 tuning, and which part of the code needed to be updated to work the
 260 same way as the current pid.c implementation.  I started by trying to
 261 isolate relevant changes in pid.c, and applying them to at_pid.c.  My
 262 aim was to make sure the at_pid component could replace the pid
 263 component with a simple change in the HAL setup loadrt line, without
 264 having to "rewire" the rest of the HAL configuration.  After a few
 265 hours following this approach, I had learned quite a lot about the
 266 code structure of both components, while concluding I was heading down
 267 the wrong rabbit hole, and should get back to the surface and find a
 268 different path.</p>
 269
 270 <p>For the second attempt, I decided to throw away all the PID control
 271 related part of the original at_pid.c, and instead isolate and lift
 272 the auto tuning part of the code and inject it into a copy of pid.c.
 273 This ensured compatibility with the current pid component, while
 274 adding auto tuning as a run time option.  To make it easier to identify
 275 the relevant parts in the future, I wrapped all the auto tuning code
 276 with '#ifdef AUTO_TUNER'.  The end result behave just like the current
 277 pid component by default, as that part of the code is identical.  The
 278 <a href="https://github.com/LinuxCNC/linuxcnc/pull/1820">end result
 279 entered the LinuxCNC master branch</a> a few days ago.</p>
 280
 281 <p>To enable auto tuning, one need to set a few HAL pins in the PID
 282 component.  The most important ones are <tt>tune-effort</tt>,
 283 <tt>tune-mode</tt> and <tt>tune-start</tt>.  But lets take a step
 284 back, and see what the auto tuning code will do.  I do not know the
 285 mathematical foundation of the at_pid algorithm, but from observation
 286 I can tell that the algorithm will, when enabled, produce a square
 287 wave pattern centered around the <tt>bias</tt> value on the output pin
 288 of the PID controller.  This can be seen using the HAL Scope provided
 289 by LinuxCNC.  In my case, this is translated into voltage (+-10V) sent
 290 to the motor controller, which in turn is translated into motor speed.
 291 So at_pid will ask the motor to move the axis back and forth.  The
 292 number of cycles in the pattern is controlled by the
 293 <tt>tune-cycles</tt> pin, and the extremes of the wave pattern is
 294 controlled by the <tt>tune-effort</tt> pin.  Of course, trying to
 295 change the direction of a physical object instantly (as in going
 296 directly from a positive voltage to the equivalent negative voltage)
 297 do not change velocity instantly, and it take some time for the object
 298 to slow down and move in the opposite direction.  This result in a
 299 more smooth movement wave form, as the axis in question were vibrating
 300 back and forth.  When the axis reached the target speed in the
 301 opposing direction, the auto tuner change direction again.  After
 302 several of these changes, the average time delay between the 'peaks'
 303 and 'valleys' of this movement graph is then used to calculate
 304 proposed values for Pgain, Igain and Dgain, and insert them into the
 305 HAL model to use by the pid controller.  The auto tuned settings are
 306 not great, but htye work a lot better than the values I had been able
 307 to cook up on my own, at least for the horizontal X and Y axis.  But I
 308 had to use very small <tt>tune-effort<tt> values, as my motor
 309 controllers error out if the voltage change too quickly.  I've been
 310 less lucky with the Z axis, which is moving a heavy object up and
 311 down, and seem to confuse the algorithm.  The Z axis movement became a
 312 lot better when I introduced a <tt>bias</tt> value to counter the
 313 gravitational drag, but I will have to work a lot more on the Z axis
 314 PID values.</p>
 315
 316 <p>Armed with this knowledge, it is time to look at how to do the
 317 tuning.  Lets say the HAL configuration in question load the PID
 318 component for X, Y and Z like this:</p>
 319
 320 <blockquote><pre>
 321 loadrt pid names=pid.x,pid.y,pid.z
 322 </pre></blockquote>
 323
 324 <p>Armed with the new and improved at_pid component, the new line will
 325 look like this:</p>
 326
 327 <blockquote><pre>
 328 loadrt at_pid names=pid.x,pid.y,pid.z
 329 </pre></blockquote>
 330
 331 <p>The rest of the HAL setup can stay the same.  This work because the
 332 components are referenced by name.  If the component had used count=3
 333 instead, all use of pid.# had to be changed to at_pid.#.</p>
 334
 335 <p>To start tuning the X axis, move the axis to the middle of its
 336 range, to make sure it do not hit anything when it start moving back
 337 and forth.  Next, set the <tt>tune-effort</tt> to a low number in the
 338 output range.  I used 0.1 as my initial value.  Next, assign 1 to the
 339 <tt>tune-mode</tt> value. Note, this will disable the pid controlling
 340 part and feed 0 to the output pin, which in my case initially caused a
 341 lot of drift.  In my case it proved to be a good idea with X and Y to
 342 tune the motor driver to make sure 0 voltage stopped the motor
 343 rotation.  On the other hand, for the Z axis this proved to be a bad
 344 idea, so it will depend on your setup.  It might help to set the
 345 <tt>bias</tt> value to a output value that reduce or eliminate the
 346 axis drift.  Finally, after setting <tt>tune-mode</tt>, set
 347 <tt>tune-start</tt> to 1 to activate the auto tuning.  If all go well,
 348 your axis will vibrate for a few seconds and when it is done, new
 349 values for Pgain, Igain and Dgain will be active.  To test them,
 350 change <tt>tune-mode</tt> back to 0.  Note that this might cause the
 351 machine to suddenly jerk as it bring the axis back to its commanded
 352 position, which it might have drifted away from during tuning.  To
 353 summarize with some halcmd lines:</p>
 354
 355 <blockquote><pre>
 356 setp pid.x.tune-effort 0.1
 357 setp pid.x.tune-mode 1
 358 setp pid.x.tune-start 1
 359 # wait for the tuning to complete
 360 setp pid.x.tune-mode 0
 361 </pre></blockquote>
 362
 363 <p>After doing this task quite a few times while trying to figure out
 364 how to properly tune the PID controllers on the machine in, I decided
 365 to figure out if this process could be automated, and wrote a script
 366 to do the entire tuning process from power on.  The end result will
 367 ensure the machine is powered on and ready to run, home all axis if it
 368 is not already done, check that the extra tuning pins are available,
 369 move the axis to its mid point, run the auto tuning and re-enable the
 370 pid controller when it is done.  It can be run several times.  Check
 371 out the
 372 <a href="https://github.com/SebKuzminsky/MazakVQC1540/blob/bon-dev/scripts/run-auto-pid-tuner">run-auto-pid-tuner</a>
 373 script on github if you want to learn how it is done.</p>
 374
 375 <p>My hope is that this little adventure can inspire someone who know
 376 more about motor PID controller tuning can implement even better
 377 algorithms for automatic PID tuning in LinuxCNC, making life easier
 378 for both me and all the others that want to use LinuxCNC but lack the
 379 in depth knowledge needed to tune PID controllers well.</p>
 380
 381 <p>As usual, if you use Bitcoin and want to show your support of my
 382 activities, please send Bitcoin donations to my address
 383 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 384 </div>
 385       <div class="tags">
 386
 387
 388         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>.
 389
 390
 391       </div>
 392     </div>
 393     <div class="padding"></div>
 394
 395     <div class="entry">
 396       <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>
 397       <div class="date">20th June 2022</div>
 398       <div class="body"><p>I guess it is time to bring some light on the various free software
 399 and open culture activities and projects I have worked on or been
 400 involved in the last year and a half.</p>
 401
 402 <p>First, lets mention the book
 403 <a href="http://www.hungry.com/~pere/publisher/">releases I managed to
 404 publish</a>.  The Cory Doctorow book "Hvordan knuse
 405 overvåkningskapitalismen" argue that it is not the magic machine
 406 learning of the big technology companies that causes the surveillance
 407 capitalism to thrive, it is the lack of trust busting to enforce
 408 existing anti-monopoly laws.  I also published a family of
 409 dictionaries for machinists, one sorted on the English words, one
 410 sorted on the Norwegian and the last sorted on the North Sámi words.
 411 A bit on the back burner but not forgotten is the Debian
 412 Administrators Handbook, where a new edition is being worked on.  I
 413 have not spent as much time as I want to help bring it to completion,
 414 but hope I will get more spare time to look at it before the end of
 415 the year.</p>
 416
 417 <p>With my Debian had I have spent time on several projects, both
 418 updating existing packages, helping to bring in new packages and
 419 working with upstream projects to try to get them ready to go into
 420 Debian.  The list is rather long, and I will only mention my own
 421 isenkram, openmotor, vlc bittorrent plugin, xprintidle, norwegian
 422 letter style for latex, bs1770gain, and recordmydesktop.  In addition
 423 to these I have sponsored several packages into Debian, like audmes.</p>
 424
 425 <p>The last year I have looked at several infrastructure projects for
 426 collecting meter data and video surveillance recordings.  This include
 427 several ONVIF related tools like onvifviewer and zoneminder as well as
 428 rtl-433, wmbusmeters and rtl-wmbus.</p>
 429
 430 <p>In parallel with this I have looked at fabrication related free
 431 software solutions like pycam and LinuxCNC.  The latter recently
 432 gained improved translation support using po4a and weblate, which was
 433 a harder nut to crack that I had anticipated when I started.</p>
 434
 435 <p>Several hours have been spent translating free software to
 436 Norwegian Bokmål on the Weblate hosted service.  Do not have a
 437 complete list, but you will find my contributions in at least gnucash,
 438 minetest and po4a.</p>
 439
 440 <p>I also spent quite some time on the Norwegian archiving specification
 441 Noark 5, and its companion project Nikita implementing the API
 442 specification for Noark 5.</p>
 443
 444 <p>Recently I have been looking into free software tools to do company
 445 accounting here in Norway., which present an interesting mix between
 446 law, rules, regulations, format specifications and API interfaces.</p>
 447
 448 <p>I guess I should also mention the Norwegian community driven
 449 government interfacing projects Mimes Brønn and Fiksgatami, which have
 450 ended up in a kind of limbo while the future of the projects is being
 451 worked out.</p>
 452
 453 <p>These are just a few of the projects I have been involved it, and
 454 would like to give more visibility.  I'll stop here to avoid delaying
 455 this post.</p>
 456
 457 <p>As usual, if you use Bitcoin and want to show your support of my
 458 activities, please send Bitcoin donations to my address
 459 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 460 </div>
 461       <div class="tags">
 462
 463
 464         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 465
 466
 467       </div>
 468     </div>
 469     <div class="padding"></div>
 470
 471     <div class="entry">
 472       <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>
 473       <div class="date"> 3rd June 2022</div>
 474       <div class="body"><p>Back in oktober last year, when I started looking at the
 475 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a> system, I
 476 proposed to change the documentation build system make life easier for
 477 translators.  The original system consisted of independently written
 478 documentation files for each language, with no automated way to track
 479 changes done in other translations and no help for the translators to
 480 know how much was left to translated.  By using
 481 <a href="https://po4a.org/">the po4a system</a> to generate POT and PO
 482 files from the English documentation, this can be improved.  A small
 483 team of LinuxCNC contributors got together and today our labour
 484 finally payed off.  Since a few hours ago, it is now possible to
 485 translate <a href="https://hosted.weblate.org/projects/linuxcnc/">the
 486 LinuxCNC documentation on Weblate</a>, alongside the program itself.</p>
 487
 488 <p>The effort to migrate the documentation to use po4a has been both
 489 slow and frustrating.  I am very happy we finally made it.</p>
 490
 491 <p>As usual, if you use Bitcoin and want to show your support of my
 492 activities, please send Bitcoin donations to my address
 493 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 494 </div>
 495       <div class="tags">
 496
 497
 498         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>.
 499
 500
 501       </div>
 502     </div>
 503     <div class="padding"></div>
 504
 505     <div class="entry">
 506       <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>
 507       <div class="date">20th April 2022</div>
 508       <div class="body"><p>Recently I wanted to upgrade the firmware of my thinkpad, and
 509 located the firmware download page from Lenovo (which annoyingly do
 510 not allow access via Tor, forcing me to hand them more personal
 511 information that I would like).  The
 512 <a href="https://support.lenovo.com/no/en/search?query=thinkpad firmware bios upgrade iso&SearchType=Customer search&searchLocation=Masthead">download
 513 from Lenovo</a> is a bootable ISO image, which is a bit of a problem
 514 when all I got available is a USB memory stick.  I tried booting the
 515 ISO as a USB stick, but this did not work.  But genisoimage came to
 516 the rescue.</p>
 517
 518 <P>The geteltorito program in
 519 <a href="http://tracker.debian.org/cdrkit">the genisoimage binary
 520 package</a> is able to convert the bootable ISO image to a bootable
 521 USB stick using a simple command line recipe, which I then can write
 522 to the most recently inserted USB stick:</p>
 523
 524 <blockquote><pre>
 525 geteltorito -o usbstick.img lenovo-firmware.iso
 526 sudo dd bs=10M if=usbstick.img of=$(ls -tr /dev/sd?|tail -1)
 527 </pre></blockquote>
 528
 529 <p>This USB stick booted the firmware upgrader just fine, and in a few
 530 minutes my machine had the latest and greatest BIOS firmware in place.</p>
 531 </div>
 532       <div class="tags">
 533
 534
 535         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>.
 536
 537
 538       </div>
 539     </div>
 540     <div class="padding"></div>
 541
 542     <div class="entry">
 543       <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>
 544       <div class="date">16th April 2022</div>
 545       <div class="body"><p>Inspired by the recent news of
 546 <a href="https://slashdot.org/story/22/04/03/2039219/intel-beats-amd-and-nvidia-with-arc-gpus-full-av1-support">AV1
 547 hardware encoding support from Intel</a>, I decided to look into
 548 the state of AV1 on Linux today.  AV1 is a
 549 <a href="https://web.archive.org/web/20160618103850/http://www.digistan.org/open-standard:definition">free
 550 and open standard</a> as defined by Digistan without any royalty
 551 payment requirement, unlike its much used competitor encoding
 552 H.264.  While looking, I came across an 5 year
 553 <a href="https://askubuntu.com/questions/1061908/how-to-encode-and-playback-video-with-the-av1-codec-on-bionic-beaver-18-04">old
 554 question on askubuntu.com</a> which in turn inspired me to check out
 555 how things are in Debian Stable regarding AV1.  The test file listed
 556 in the question (askubuntu_test_aom.mp4) did not exist any more, so I
 557 tracked down a different set of test files on
 558 <a href="https://av1.webmfiles.org/">av1.webmfiles.org</a> to test them
 559 with the various video tools I had installed on my machine.  I was
 560 happy to discover that AV1 decoding and playback worked with almost
 561 every tool I tested:
 562
 563 <table align="center">
 564 <tr><td>mediainfo</td>       <td>ok</td></tr>
 565 <tr><td>dragonplayer</td>    <td>ok</td></tr>
 566 <tr><td>ffmpeg / ffplay</td> <td>ok</td></tr>
 567 <tr><td>gnome-mplayer</td>   <td>fail</td></tr>
 568 <tr><td>mplayer</td>         <td>ok</td></tr>
 569 <tr><td>mpv</td>             <td>ok</td></tr>
 570 <tr><td>parole</td>          <td>ok</td></tr>
 571 <tr><td>vlc</td>             <td>ok</td></tr>
 572 <tr><td>firefox</td>         <td>ok</td></tr>
 573 <tr><td>chromium</td>        <td>ok</td></tr>
 574 </table>
 575
 576 <p>AV1 encoding is available in Debian Stable from the aom-tools
 577 version 1.0.0.errata1-3 package, using the aomenc tool.  The encoding
 578 using the package in Debian Stable is quite slow, with the frame rate
 579 for my 10 second test video at around 0.25 fps.  My 10 second video
 580 test took 16 minutes and 11 seconds on my test machine.</p>
 581
 582 <p>I tested by first running ffmpeg and then aomenc using the recipe
 583 provided by the askubuntu recipe above.  I had to remove the
 584 '--row-mt=1' option, as it was not supported in my 1.0.0 version.  The
 585 encoding only used a single thread, according to <tt>top</tt>.</p>
 586
 587 <blockquote><pre>
 588 ffmpeg -i some-old-video.ogv -t 10 -pix_fmt yuv420p video.y4m
 589 aomenc --fps=24/1 -u 0 --codec=av1 --target-bitrate=1000 \
 590   --lag-in-frames=25 --auto-alt-ref=1 -t 24 --cpu-used=8 \
 591   --tile-columns=2 --tile-rows=2 -o output.webm video.y4m
 592 </pre></blockquote>
 593
 594 <p>As version 1.0.0 currently have several
 595 <a href="https://security-tracker.debian.org/tracker/source-package/aom">unsolved
 596 security issues in Debian Stable</a>, and to see if the recent
 597 backport <a href="https://tracker.debian.org/pkg/aom">provided in
 598 Debian</a> is any quicker, I ran <tt>apt -t bullseye-backports install
 599 aom-tools</tt> to fetch the backported version and re-encoded the
 600 video using the latest version.  This time the '--row-mt=1' option
 601 worked, and the encoding was done in 46 seconds with a frame rate of
 602 around 5.22 fps.  This time it seem to be using all my four cores to
 603 encode.  Encoding speed is still too low for streaming and real time,
 604 which would require frame rates above 25 fps, but might be good enough
 605 for offline encoding.</p>
 606
 607 <p>I am very happy to see AV1 playback working so well with the
 608 default tools in Debian Stable.  I hope the encoding situation improve
 609 too, allowing even a slow old computer like my 10 year old laptop to
 610 be used for encoding.</p>
 611
 612 <p>As usual, if you use Bitcoin and want to show your support of my
 613 activities, please send Bitcoin donations to my address
 614 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 615 </div>
 616       <div class="tags">
 617
 618
 619         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>.
 620
 621
 622       </div>
 623     </div>
 624     <div class="padding"></div>
 625
 626     <div class="entry">
 627       <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>
 628       <div class="date">14th March 2022</div>
 629       <div class="body"><p>På onsdag sendte jeg følgende epost til Utdanningsetaten i Oslo
 630 kommune (UDE).  Fikk beskjed om at min henvendelse har saksnummer
 631 22/7559-1 i den
 632 <a href="https://www.oslo.kommune.no/etater-foretak-og-ombud/utdanningsetaten/postjournal-utdanningsetaten/">offentlige
 633 postjournalen til UDE</a>.  Jeg er spent på hva slags respons jeg får.
 634 Mistenker jo de fleste som sprer sine nettsideleseres
 635 personopplysninger til utlandet ikke har tenkt så nøye igjennom hva de
 636 gjør, og at det er håp om at de tenker seg litt nøyere om hvis de blir
 637 klar over problemstillingen.  Vet du noen som burde få tilsvarede
 638 beskjed og spørsmål?  Kanskje du kan sende dem en epost.  Hvis alle
 639 bidrar blir det kanskje litt bedre.</p>
 640
 641 <blockquote>
 642 <p>To: postmottak (at) osloskolen.no
 643 <br>Subject: Digitale utslipp fra osloskolens nettsider</p>
 644
 645 <p>Hei.</p>
 646
 647 <p>Jeg ser at osloskolens nettsider har digitale utslipp av
 648 personopplysninger til Google, Facebook og andre, blant annet omtalt
 649 på &lt;URL: <a href="https://aktuelt.osloskolen.no/personvernerklaring-for-osloskolen/informasjonskapsler/">https://aktuelt.osloskolen.no/personvernerklaring-for-osloskolen/informasjonskapsler/</a>
 650 >.</p>
 651
 652 <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>
 653
 654 <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>
 655
 656 <p>Et alternativ til Google Analytics kan være en lokalt installert
 657 utgave av &lt;URL:
 658 <a href="https://matomo.org/">https://matomo.org/</a> >.  Den og flere
 659 andre alternativer kan finnes via
 660 &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> >
 661 på bakgrunn av at svenske myndigheter har innsett at dagens praksis
 662 nok er både lite lur og ulovlig.  Der henger Norge litt etter, men
 663 osloskolen har her mulighet til å være litt i forkant. :)</p>
 664
 665 <p>Fint om dere kan gi beskjed hvilket saksnummer denne henvendelsen får i
 666 offentlig postjournal når den er mottatt.</p>
 667
 668 </blockquote>
 669
 670 </p>Flere og flere innser at slik spredning av personopplysninger er
 671 ugreit.  Det har pågått i mange år.  Ser jeg blogget
 672 <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
 673 gang om Google Analytics i 2013</a> og
 674 <a href="https://people.skolelinux.org/pere/blog/Snurpenot_overv_kning_av_sensitiv_personinformasjon.html">analyserte
 675 omfanget i 2015</a>, men det er et langt lerret å bleke.</p>
 676
 677 <p>Som vanlig, hvis du bruker Bitcoin og ønsker å vise din støtte til
 678 det jeg driver med, setter jeg pris på om du sender Bitcoin-donasjoner
 679 til min adresse
 680 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.
 681 Merk, betaling med bitcoin er ikke anonymt. :)</p>
 682 </div>
 683       <div class="tags">
 684
 685
 686         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>.
 687
 688
 689       </div>
 690     </div>
 691     <div class="padding"></div>
 692
 693     <div class="entry">
 694       <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>
 695       <div class="date">12th March 2022</div>
 696       <div class="body"><p>Recently I had a look at a
 697 <a href="https://www.hargassner.at/">Hargassner</a>
 698 <a href="https://www.hargassner.at/en/products/wood-chip-boiler.html">wood
 699 chip boiler</a>, and what kind of free software can be used to monitor
 700 and control it.  The boiler can be connected to some cloud service via
 701 what the producer call an Internet Gateway, which seem to be a
 702 computer connecting to the boiler and passing the information gathered
 703 to the cloud.  I discovered the boiler controller got an IP address on
 704 the local network and listen on TCP port 23 to provide status
 705 information as a text line of numbers.  It also provide a HTTP server
 706 listening on port 80, but I have not yet figured out what it can do
 707 beside return an error code.</p>
 708
 709 <p>If I am to believe various free software implementations talking to
 710 such boiler, the interpretation of the line of numbers differ between
 711 type of boiler and software version on the boiler.  By comparing the
 712 list of numbers on the front panel of the boiler with the numbers
 713 returned via TCP, I have been able to figure out several of the
 714 numbers, but there are a lot left to understand.  I've located several
 715 temperature measurements and hours running values, as well as oxygen
 716 measurements and counters.</p>
 717
 718 I decided to write a simple parser in Python for the values I figured
 719 out so far, and a simple MQTT injector publishing both the interpreted
 720 and the unknown values on a MQTT bus to make collecting and graphing
 721 simpler.  The end result is available from the
 722 <a href="https://gitlab.com/petterreinholdtsen/hargassner2mqtt">hargassner2mqtt
 723 project page</a> on gitlab.  I very much welcome patches extending the
 724 parser to understand more values, boiler types and software versions.
 725 I do not really expect very few free software developers got their
 726 hands on such unit to experiment, but it would be fun if others too find
 727 this project useful.</p>
 728
 729 <p>As usual, if you use Bitcoin and want to show your support of my
 730 activities, please send Bitcoin donations to my address
 731 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 732 </div>
 733       <div class="tags">
 734
 735
 736         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 737
 738
 739       </div>
 740     </div>
 741     <div class="padding"></div>
 742
 743     <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>
 744     <div id="sidebar">
 745
 746
 747
 748 <h2>Archive</h2>
 749 <ul>
 750
 751 <li>2022
 752 <ul>
 753
 754 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/02/">February (1)</a></li>
 755
 756 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/03/">March (3)</a></li>
 757
 758 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/04/">April (2)</a></li>
 759
 760 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/06/">June (2)</a></li>
 761
 762 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/07/">July (1)</a></li>
 763
 764 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/09/">September (1)</a></li>
 765
 766 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/10/">October (1)</a></li>
 767
 768 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/12/">December (1)</a></li>
 769
 770 </ul></li>
 771
 772 <li>2021
 773 <ul>
 774
 775 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/01/">January (2)</a></li>
 776
 777 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/02/">February (1)</a></li>
 778
 779 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/05/">May (1)</a></li>
 780
 781 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/06/">June (1)</a></li>
 782
 783 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/07/">July (3)</a></li>
 784
 785 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/08/">August (1)</a></li>
 786
 787 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/09/">September (1)</a></li>
 788
 789 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/10/">October (1)</a></li>
 790
 791 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/12/">December (1)</a></li>
 792
 793 </ul></li>
 794
 795 <li>2020
 796 <ul>
 797
 798 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/02/">February (2)</a></li>
 799
 800 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/03/">March (2)</a></li>
 801
 802 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/04/">April (2)</a></li>
 803
 804 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/05/">May (3)</a></li>
 805
 806 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/06/">June (2)</a></li>
 807
 808 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/07/">July (1)</a></li>
 809
 810 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/09/">September (1)</a></li>
 811
 812 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/10/">October (1)</a></li>
 813
 814 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/11/">November (1)</a></li>
 815
 816 </ul></li>
 817
 818 <li>2019
 819 <ul>
 820
 821 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/01/">January (4)</a></li>
 822
 823 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/02/">February (3)</a></li>
 824
 825 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/03/">March (3)</a></li>
 826
 827 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/05/">May (2)</a></li>
 828
 829 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/06/">June (5)</a></li>
 830
 831 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/07/">July (2)</a></li>
 832
 833 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/08/">August (1)</a></li>
 834
 835 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/09/">September (1)</a></li>
 836
 837 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/11/">November (1)</a></li>
 838
 839 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/12/">December (4)</a></li>
 840
 841 </ul></li>
 842
 843 <li>2018
 844 <ul>
 845
 846 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/01/">January (1)</a></li>
 847
 848 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/02/">February (5)</a></li>
 849
 850 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/03/">March (5)</a></li>
 851
 852 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/04/">April (3)</a></li>
 853
 854 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/06/">June (2)</a></li>
 855
 856 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/07/">July (5)</a></li>
 857
 858 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/08/">August (3)</a></li>
 859
 860 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/09/">September (3)</a></li>
 861
 862 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/10/">October (5)</a></li>
 863
 864 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/11/">November (2)</a></li>
 865
 866 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/12/">December (4)</a></li>
 867
 868 </ul></li>
 869
 870 <li>2017
 871 <ul>
 872
 873 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/01/">January (4)</a></li>
 874
 875 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/02/">February (3)</a></li>
 876
 877 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/03/">March (5)</a></li>
 878
 879 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/04/">April (2)</a></li>
 880
 881 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/06/">June (5)</a></li>
 882
 883 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/07/">July (1)</a></li>
 884
 885 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/08/">August (1)</a></li>
 886
 887 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/09/">September (3)</a></li>
 888
 889 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/10/">October (5)</a></li>
 890
 891 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/11/">November (3)</a></li>
 892
 893 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/12/">December (4)</a></li>
 894
 895 </ul></li>
 896
 897 <li>2016
 898 <ul>
 899
 900 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/01/">January (3)</a></li>
 901
 902 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/02/">February (2)</a></li>
 903
 904 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/03/">March (3)</a></li>
 905
 906 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/04/">April (8)</a></li>
 907
 908 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/05/">May (8)</a></li>
 909
 910 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/06/">June (2)</a></li>
 911
 912 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/07/">July (2)</a></li>
 913
 914 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/08/">August (5)</a></li>
 915
 916 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/09/">September (2)</a></li>
 917
 918 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/10/">October (3)</a></li>
 919
 920 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/11/">November (8)</a></li>
 921
 922 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/12/">December (5)</a></li>
 923
 924 </ul></li>
 925
 926 <li>2015
 927 <ul>
 928
 929 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
 930
 931 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
 932
 933 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
 934
 935 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
 936
 937 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/05/">May (3)</a></li>
 938
 939 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/06/">June (4)</a></li>
 940
 941 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/07/">July (6)</a></li>
 942
 943 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/08/">August (2)</a></li>
 944
 945 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/09/">September (2)</a></li>
 946
 947 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/10/">October (9)</a></li>
 948
 949 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/11/">November (6)</a></li>
 950
 951 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/12/">December (3)</a></li>
 952
 953 </ul></li>
 954
 955 <li>2014
 956 <ul>
 957
 958 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
 959
 960 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
 961
 962 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
 963
 964 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
 965
 966 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
 967
 968 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
 969
 970 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
 971
 972 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
 973
 974 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
 975
 976 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
 977
 978 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
 979
 980 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
 981
 982 </ul></li>
 983
 984 <li>2013
 985 <ul>
 986
 987 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 988
 989 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 990
 991 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 992
 993 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 994
 995 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 996
 997 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 998
 999 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
1000
1001 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
1002
1003 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
1004
1005 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
1006
1007 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
1008
1009 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
1010
1011 </ul></li>
1012
1013 <li>2012
1014 <ul>
1015
1016 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
1017
1018 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
1019
1020 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
1021
1022 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
1023
1024 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
1025
1026 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
1027
1028 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
1029
1030 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
1031
1032 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
1033
1034 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
1035
1036 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
1037
1038 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
1039
1040 </ul></li>
1041
1042 <li>2011
1043 <ul>
1044
1045 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
1046
1047 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
1048
1049 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
1050
1051 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
1052
1053 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
1054
1055 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
1056
1057 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
1058
1059 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
1060
1061 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
1062
1063 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
1064
1065 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
1066
1067 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
1068
1069 </ul></li>
1070
1071 <li>2010
1072 <ul>
1073
1074 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
1075
1076 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
1077
1078 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
1079
1080 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
1081
1082 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
1083
1084 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
1085
1086 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
1087
1088 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
1089
1090 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
1091
1092 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
1093
1094 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
1095
1096 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
1097
1098 </ul></li>
1099
1100 <li>2009
1101 <ul>
1102
1103 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
1104
1105 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
1106
1107 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
1108
1109 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
1110
1111 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
1112
1113 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
1114
1115 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
1116
1117 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
1118
1119 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
1120
1121 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
1122
1123 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
1124
1125 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
1126
1127 </ul></li>
1128
1129 <li>2008
1130 <ul>
1131
1132 <li><a href="https://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
1133
1134 <li><a href="https://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
1135
1136 </ul></li>
1137
1138 </ul>
1139
1140
1141
1142 <h2>Tags</h2>
1143 <ul>
1144
1145  <li><a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (19)</a></li>
1146
1147  <li><a href="https://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
1148
1149  <li><a href="https://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
1150
1151  <li><a href="https://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
1152
1153  <li><a href="https://people.skolelinux.org/pere/blog/tags/betalkontant">betalkontant (9)</a></li>
1154
1155  <li><a href="https://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (12)</a></li>
1156
1157  <li><a href="https://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (17)</a></li>
1158
1159  <li><a href="https://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
1160
1161  <li><a href="https://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
1162
1163  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian">debian (184)</a></li>
1164
1165  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (159)</a></li>
1166
1167  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook (9)</a></li>
1168
1169  <li><a href="https://people.skolelinux.org/pere/blog/tags/digistan">digistan (11)</a></li>
1170
1171  <li><a href="https://people.skolelinux.org/pere/blog/tags/dld">dld (18)</a></li>
1172
1173  <li><a href="https://people.skolelinux.org/pere/blog/tags/docbook">docbook (30)</a></li>
1174
1175  <li><a href="https://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
1176
1177  <li><a href="https://people.skolelinux.org/pere/blog/tags/english">english (440)</a></li>
1178
1179  <li><a href="https://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
1180
1181  <li><a href="https://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (14)</a></li>
1182
1183  <li><a href="https://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (34)</a></li>
1184
1185  <li><a href="https://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
1186
1187  <li><a href="https://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (20)</a></li>
1188
1189  <li><a href="https://people.skolelinux.org/pere/blog/tags/h264">h264 (20)</a></li>
1190
1191  <li><a href="https://people.skolelinux.org/pere/blog/tags/intervju">intervju (43)</a></li>
1192
1193  <li><a href="https://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (16)</a></li>
1194
1195  <li><a href="https://people.skolelinux.org/pere/blog/tags/kart">kart (23)</a></li>
1196
1197  <li><a href="https://people.skolelinux.org/pere/blog/tags/kodi">kodi (4)</a></li>
1198
1199  <li><a href="https://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
1200
1201  <li><a href="https://people.skolelinux.org/pere/blog/tags/lego">lego (5)</a></li>
1202
1203  <li><a href="https://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
1204
1205  <li><a href="https://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
1206
1207  <li><a href="https://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
1208
1209  <li><a href="https://people.skolelinux.org/pere/blog/tags/madewithcc">madewithcc (3)</a></li>
1210
1211  <li><a href="https://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
1212
1213  <li><a href="https://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (44)</a></li>
1214
1215  <li><a href="https://people.skolelinux.org/pere/blog/tags/nice free software">nice free software (13)</a></li>
1216
1217  <li><a href="https://people.skolelinux.org/pere/blog/tags/noark5">noark5 (23)</a></li>
1218
1219  <li><a href="https://people.skolelinux.org/pere/blog/tags/norsk">norsk (320)</a></li>
1220
1221  <li><a href="https://people.skolelinux.org/pere/blog/tags/nuug">nuug (198)</a></li>
1222
1223  <li><a href="https://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (40)</a></li>
1224
1225  <li><a href="https://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
1226
1227  <li><a href="https://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (75)</a></li>
1228
1229  <li><a href="https://people.skolelinux.org/pere/blog/tags/personvern">personvern (114)</a></li>
1230
1231  <li><a href="https://people.skolelinux.org/pere/blog/tags/raid">raid (2)</a></li>
1232
1233  <li><a href="https://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
1234
1235  <li><a href="https://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
1236
1237  <li><a href="https://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
1238
1239  <li><a href="https://people.skolelinux.org/pere/blog/tags/robot">robot (16)</a></li>
1240
1241  <li><a href="https://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
1242
1243  <li><a href="https://people.skolelinux.org/pere/blog/tags/ruter">ruter (7)</a></li>
1244
1245  <li><a href="https://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
1246
1247  <li><a href="https://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (59)</a></li>
1248
1249  <li><a href="https://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
1250
1251  <li><a href="https://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (5)</a></li>
1252
1253  <li><a href="https://people.skolelinux.org/pere/blog/tags/standard">standard (74)</a></li>
1254
1255  <li><a href="https://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (7)</a></li>
1256
1257  <li><a href="https://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (14)</a></li>
1258
1259  <li><a href="https://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (64)</a></li>
1260
1261  <li><a href="https://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (5)</a></li>
1262
1263  <li><a href="https://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
1264
1265  <li><a href="https://people.skolelinux.org/pere/blog/tags/valg">valg (9)</a></li>
1266
1267  <li><a href="https://people.skolelinux.org/pere/blog/tags/verkidetfri">verkidetfri (20)</a></li>
1268
1269  <li><a href="https://people.skolelinux.org/pere/blog/tags/video">video (77)</a></li>
1270
1271  <li><a href="https://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
1272
1273  <li><a href="https://people.skolelinux.org/pere/blog/tags/web">web (42)</a></li>
1274
1275 </ul>
1276
1277
1278     </div>
1279     <p style="text-align: right">
1280  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
1281 </p>
1282
1283   </body>
1284 </html>