1 <?xml version=
"1.0" encoding=
"utf-8"?>
2 <rss version='
2.0' xmlns:lj='http://www.livejournal.org/rss/lj/
1.0/' xmlns:
atom=
"http://www.w3.org/2005/Atom">
4 <title>Petter Reinholdtsen
</title>
5 <description></description>
6 <link>http://people.skolelinux.org/pere/blog/
</link>
7 <atom:link href=
"http://people.skolelinux.org/pere/blog/index.rss" rel=
"self" type=
"application/rss+xml" />
10 <title>Web services for writing academic LaTeX papers as a team
</title>
11 <link>http://people.skolelinux.org/pere/blog/Web_services_for_writing_academic_LaTeX_papers_as_a_team.html
</link>
12 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Web_services_for_writing_academic_LaTeX_papers_as_a_team.html
</guid>
13 <pubDate>Tue,
31 Oct
2017 21:
00:
00 +
0100</pubDate>
14 <description><p
>I was surprised today to learn that a friend in academia did not
15 know there are easily available web services available for writing
16 LaTeX documents as a team. I thought it was common knowledge, but to
17 make sure at least my readers are aware of it, I would like to mention
18 these useful services for writing LaTeX documents. Some of them even
19 provide a WYSIWYG editor to ease writing even further.
</p
>
21 <p
>There are two commercial services available,
22 <a href=
"https://sharelatex.com
">ShareLaTeX
</a
> and
23 <a href=
"https://overleaf.com
">Overleaf
</a
>. They are very easy to
24 use. Just start a new document, select which publisher to write for
25 (ie which LaTeX style to use), and start writing. Note, these two
26 have announced their intention to join forces, so soon it will only be
27 one joint service. I
've used both for different documents, and they
29 <a href=
"https://github.com/sharelatex/sharelatex
">ShareLaTeX is free
30 software
</a
>, while the latter is not. According to
<a
31 href=
"https://www.overleaf.com/help/
17-is-overleaf-open-source
">a
32 announcement from Overleaf
</a
>, they plan to keep the ShareLaTeX code
33 base maintained as free software.
</p
>
35 But these two are not the only alternatives.
36 <a href=
"https://app.fiduswriter.org/
">Fidus Writer
</a
> is another free
37 software solution with
<a href=
"https://github.com/fiduswriter
">the
38 source available on github
</a
>. I have not used it myself. Several
39 others can be found on the nice
40 <a href=
"https://alternativeto.net/software/sharelatex/
">alterntiveTo
41 web service
</a
>.
43 <p
>If you like Google Docs or Etherpad, but would like to write
44 documents in LaTeX, you should check out these services. You can even
45 host your own, if you want to. :)
</p
>
51 <title>Locating IMDB IDs of movies in the Internet Archive using Wikidata
</title>
52 <link>http://people.skolelinux.org/pere/blog/Locating_IMDB_IDs_of_movies_in_the_Internet_Archive_using_Wikidata.html
</link>
53 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Locating_IMDB_IDs_of_movies_in_the_Internet_Archive_using_Wikidata.html
</guid>
54 <pubDate>Wed,
25 Oct
2017 12:
20:
00 +
0200</pubDate>
55 <description><p
>Recently, I needed to automatically check the copyright status of a
56 set of
<a href=
"http://www.imdb.com/
">The Internet Movie database
57 (IMDB)
</a
> entries, to figure out which one of the movies they refer
58 to can be freely distributed on the Internet. This proved to be
59 harder than it sounds. IMDB for sure list movies without any
60 copyright protection, where the copyright protection has expired or
61 where the movie is lisenced using a permissive license like one from
62 Creative Commons. These are mixed with copyright protected movies,
63 and there seem to be no way to separate these classes of movies using
64 the information in IMDB.
</p
>
66 <p
>First I tried to look up entries manually in IMDB,
67 <a href=
"https://www.wikipedia.org/
">Wikipedia
</a
> and
68 <a href=
"https://www.archive.org/
">The Internet Archive
</a
>, to get a
69 feel how to do this. It is hard to know for sure using these sources,
70 but it should be possible to be reasonable confident a movie is
"out
71 of copyright
" with a few hours work per movie. As I needed to check
72 almost
20,
000 entries, this approach was not sustainable. I simply
73 can not work around the clock for about
6 years to check this data
76 <p
>I asked the people behind The Internet Archive if they could
77 introduce a new metadata field in their metadata XML for IMDB ID, but
78 was told that they leave it completely to the uploaders to update the
79 metadata. Some of the metadata entries had IMDB links in the
80 description, but I found no way to download all metadata files in bulk
81 to locate those ones and put that approach aside.
</p
>
83 <p
>In the process I noticed several Wikipedia articles about movies
84 had links to both IMDB and The Internet Archive, and it occured to me
85 that I could use the Wikipedia RDF data set to locate entries with
86 both, to at least get a lower bound on the number of movies on The
87 Internet Archive with a IMDB ID. This is useful based on the
88 assumption that movies distributed by The Internet Archive can be
89 legally distributed on the Internet. With some help from the RDF
90 community (thank you DanC), I was able to come up with this query to
91 pass to
<a href=
"https://query.wikidata.org/
">the SPARQL interface on
95 SELECT ?work ?imdb ?ia ?when ?label
98 ?work wdt:P31/wdt:P279* wd:Q11424.
102 ?work wdt:P577 ?when.
103 ?work rdfs:label ?label.
104 FILTER(LANG(?label) =
"en
").
107 </pre
></p
>
109 <p
>If I understand the query right, for every film entry anywhere in
110 Wikpedia, it will return the IMDB ID and The Internet Archive ID, and
111 when the movie was released and its English title, if either or both
112 of the latter two are available. At the moment the result set contain
113 2338 entries. Of course, it depend on volunteers including both
114 correct IMDB and The Internet Archive IDs in the wikipedia articles
115 for the movie. It should be noted that the result will include
116 duplicates if the movie have entries in several languages. There are
117 some bogus entries, either because The Internet Archive ID contain a
118 typo or because the movie is not available from The Internet Archive.
119 I did not verify the IMDB IDs, as I am unsure how to do that
120 automatically.
</p
>
122 <p
>I wrote a small python script to extract the data set from Wikidata
123 and check if the XML metadata for the movie is available from The
124 Internet Archive, and after around
1.5 hour it produced a list of
2097
125 free movies and their IMDB ID. In total,
171 entries in Wikidata lack
126 the refered Internet Archive entry. I assume the
70 "disappearing
"
127 entries (ie
2338-
2097-
171) are duplicate entries.
</p
>
129 <p
>This is not too bad, given that The Internet Archive report to
130 contain
<a href=
"https://archive.org/details/feature_films
">5331
131 feature films
</a
> at the moment, but it also mean more than
3000
132 movies are missing on Wikipedia or are missing the pair of references
133 on Wikipedia.
</p
>
135 <p
>I was curious about the distribution by release year, and made a
136 little graph to show how the amount of free movies is spread over the
139 <p
><img src=
"http://people.skolelinux.org/pere/blog/images/
2017-
10-
25-verk-i-det-fri-filmer.png
"></p
>
141 <p
>I expect the relative distribution of the remaining
3000 movies to
142 be similar.
</p
>
144 <p
>If you want to help, and want to ensure Wikipedia can be used to
145 cross reference The Internet Archive and The Internet Movie Database,
146 please make sure entries like this are listed under the
"External
147 links
" heading on the Wikipedia article for the movie:
</p
>
150 * {{Internet Archive film|id=FightingLady}}
151 * {{IMDb title|id=
0036823|title=The Fighting Lady}}
152 </pre
></p
>
154 <p
>Please verify the links on the final page, to make sure you did not
155 introduce a typo.
</p
>
157 <p
>Here is the complete list, if you want to correct the
171
158 identified Wikipedia entries with broken links to The Internet
159 Archive:
<a href=
"http://www.wikidata.org/entity/Q1140317
">Q1140317
</a
>,
160 <a href=
"http://www.wikidata.org/entity/Q458656
">Q458656
</a
>,
161 <a href=
"http://www.wikidata.org/entity/Q458656
">Q458656
</a
>,
162 <a href=
"http://www.wikidata.org/entity/Q470560
">Q470560
</a
>,
163 <a href=
"http://www.wikidata.org/entity/Q743340
">Q743340
</a
>,
164 <a href=
"http://www.wikidata.org/entity/Q822580
">Q822580
</a
>,
165 <a href=
"http://www.wikidata.org/entity/Q480696
">Q480696
</a
>,
166 <a href=
"http://www.wikidata.org/entity/Q128761
">Q128761
</a
>,
167 <a href=
"http://www.wikidata.org/entity/Q1307059
">Q1307059
</a
>,
168 <a href=
"http://www.wikidata.org/entity/Q1335091
">Q1335091
</a
>,
169 <a href=
"http://www.wikidata.org/entity/Q1537166
">Q1537166
</a
>,
170 <a href=
"http://www.wikidata.org/entity/Q1438334
">Q1438334
</a
>,
171 <a href=
"http://www.wikidata.org/entity/Q1479751
">Q1479751
</a
>,
172 <a href=
"http://www.wikidata.org/entity/Q1497200
">Q1497200
</a
>,
173 <a href=
"http://www.wikidata.org/entity/Q1498122
">Q1498122
</a
>,
174 <a href=
"http://www.wikidata.org/entity/Q865973
">Q865973
</a
>,
175 <a href=
"http://www.wikidata.org/entity/Q834269
">Q834269
</a
>,
176 <a href=
"http://www.wikidata.org/entity/Q841781
">Q841781
</a
>,
177 <a href=
"http://www.wikidata.org/entity/Q841781
">Q841781
</a
>,
178 <a href=
"http://www.wikidata.org/entity/Q1548193
">Q1548193
</a
>,
179 <a href=
"http://www.wikidata.org/entity/Q499031
">Q499031
</a
>,
180 <a href=
"http://www.wikidata.org/entity/Q1564769
">Q1564769
</a
>,
181 <a href=
"http://www.wikidata.org/entity/Q1585239
">Q1585239
</a
>,
182 <a href=
"http://www.wikidata.org/entity/Q1585569
">Q1585569
</a
>,
183 <a href=
"http://www.wikidata.org/entity/Q1624236
">Q1624236
</a
>,
184 <a href=
"http://www.wikidata.org/entity/Q4796595
">Q4796595
</a
>,
185 <a href=
"http://www.wikidata.org/entity/Q4853469
">Q4853469
</a
>,
186 <a href=
"http://www.wikidata.org/entity/Q4873046
">Q4873046
</a
>,
187 <a href=
"http://www.wikidata.org/entity/Q915016
">Q915016
</a
>,
188 <a href=
"http://www.wikidata.org/entity/Q4660396
">Q4660396
</a
>,
189 <a href=
"http://www.wikidata.org/entity/Q4677708
">Q4677708
</a
>,
190 <a href=
"http://www.wikidata.org/entity/Q4738449
">Q4738449
</a
>,
191 <a href=
"http://www.wikidata.org/entity/Q4756096
">Q4756096
</a
>,
192 <a href=
"http://www.wikidata.org/entity/Q4766785
">Q4766785
</a
>,
193 <a href=
"http://www.wikidata.org/entity/Q880357
">Q880357
</a
>,
194 <a href=
"http://www.wikidata.org/entity/Q882066
">Q882066
</a
>,
195 <a href=
"http://www.wikidata.org/entity/Q882066
">Q882066
</a
>,
196 <a href=
"http://www.wikidata.org/entity/Q204191
">Q204191
</a
>,
197 <a href=
"http://www.wikidata.org/entity/Q204191
">Q204191
</a
>,
198 <a href=
"http://www.wikidata.org/entity/Q1194170
">Q1194170
</a
>,
199 <a href=
"http://www.wikidata.org/entity/Q940014
">Q940014
</a
>,
200 <a href=
"http://www.wikidata.org/entity/Q946863
">Q946863
</a
>,
201 <a href=
"http://www.wikidata.org/entity/Q172837
">Q172837
</a
>,
202 <a href=
"http://www.wikidata.org/entity/Q573077
">Q573077
</a
>,
203 <a href=
"http://www.wikidata.org/entity/Q1219005
">Q1219005
</a
>,
204 <a href=
"http://www.wikidata.org/entity/Q1219599
">Q1219599
</a
>,
205 <a href=
"http://www.wikidata.org/entity/Q1643798
">Q1643798
</a
>,
206 <a href=
"http://www.wikidata.org/entity/Q1656352
">Q1656352
</a
>,
207 <a href=
"http://www.wikidata.org/entity/Q1659549
">Q1659549
</a
>,
208 <a href=
"http://www.wikidata.org/entity/Q1660007
">Q1660007
</a
>,
209 <a href=
"http://www.wikidata.org/entity/Q1698154
">Q1698154
</a
>,
210 <a href=
"http://www.wikidata.org/entity/Q1737980
">Q1737980
</a
>,
211 <a href=
"http://www.wikidata.org/entity/Q1877284
">Q1877284
</a
>,
212 <a href=
"http://www.wikidata.org/entity/Q1199354
">Q1199354
</a
>,
213 <a href=
"http://www.wikidata.org/entity/Q1199354
">Q1199354
</a
>,
214 <a href=
"http://www.wikidata.org/entity/Q1199451
">Q1199451
</a
>,
215 <a href=
"http://www.wikidata.org/entity/Q1211871
">Q1211871
</a
>,
216 <a href=
"http://www.wikidata.org/entity/Q1212179
">Q1212179
</a
>,
217 <a href=
"http://www.wikidata.org/entity/Q1238382
">Q1238382
</a
>,
218 <a href=
"http://www.wikidata.org/entity/Q4906454
">Q4906454
</a
>,
219 <a href=
"http://www.wikidata.org/entity/Q320219
">Q320219
</a
>,
220 <a href=
"http://www.wikidata.org/entity/Q1148649
">Q1148649
</a
>,
221 <a href=
"http://www.wikidata.org/entity/Q645094
">Q645094
</a
>,
222 <a href=
"http://www.wikidata.org/entity/Q5050350
">Q5050350
</a
>,
223 <a href=
"http://www.wikidata.org/entity/Q5166548
">Q5166548
</a
>,
224 <a href=
"http://www.wikidata.org/entity/Q2677926
">Q2677926
</a
>,
225 <a href=
"http://www.wikidata.org/entity/Q2698139
">Q2698139
</a
>,
226 <a href=
"http://www.wikidata.org/entity/Q2707305
">Q2707305
</a
>,
227 <a href=
"http://www.wikidata.org/entity/Q2740725
">Q2740725
</a
>,
228 <a href=
"http://www.wikidata.org/entity/Q2024780
">Q2024780
</a
>,
229 <a href=
"http://www.wikidata.org/entity/Q2117418
">Q2117418
</a
>,
230 <a href=
"http://www.wikidata.org/entity/Q2138984
">Q2138984
</a
>,
231 <a href=
"http://www.wikidata.org/entity/Q1127992
">Q1127992
</a
>,
232 <a href=
"http://www.wikidata.org/entity/Q1058087
">Q1058087
</a
>,
233 <a href=
"http://www.wikidata.org/entity/Q1070484
">Q1070484
</a
>,
234 <a href=
"http://www.wikidata.org/entity/Q1080080
">Q1080080
</a
>,
235 <a href=
"http://www.wikidata.org/entity/Q1090813
">Q1090813
</a
>,
236 <a href=
"http://www.wikidata.org/entity/Q1251918
">Q1251918
</a
>,
237 <a href=
"http://www.wikidata.org/entity/Q1254110
">Q1254110
</a
>,
238 <a href=
"http://www.wikidata.org/entity/Q1257070
">Q1257070
</a
>,
239 <a href=
"http://www.wikidata.org/entity/Q1257079
">Q1257079
</a
>,
240 <a href=
"http://www.wikidata.org/entity/Q1197410
">Q1197410
</a
>,
241 <a href=
"http://www.wikidata.org/entity/Q1198423
">Q1198423
</a
>,
242 <a href=
"http://www.wikidata.org/entity/Q706951
">Q706951
</a
>,
243 <a href=
"http://www.wikidata.org/entity/Q723239
">Q723239
</a
>,
244 <a href=
"http://www.wikidata.org/entity/Q2079261
">Q2079261
</a
>,
245 <a href=
"http://www.wikidata.org/entity/Q1171364
">Q1171364
</a
>,
246 <a href=
"http://www.wikidata.org/entity/Q617858
">Q617858
</a
>,
247 <a href=
"http://www.wikidata.org/entity/Q5166611
">Q5166611
</a
>,
248 <a href=
"http://www.wikidata.org/entity/Q5166611
">Q5166611
</a
>,
249 <a href=
"http://www.wikidata.org/entity/Q324513
">Q324513
</a
>,
250 <a href=
"http://www.wikidata.org/entity/Q374172
">Q374172
</a
>,
251 <a href=
"http://www.wikidata.org/entity/Q7533269
">Q7533269
</a
>,
252 <a href=
"http://www.wikidata.org/entity/Q970386
">Q970386
</a
>,
253 <a href=
"http://www.wikidata.org/entity/Q976849
">Q976849
</a
>,
254 <a href=
"http://www.wikidata.org/entity/Q7458614
">Q7458614
</a
>,
255 <a href=
"http://www.wikidata.org/entity/Q5347416
">Q5347416
</a
>,
256 <a href=
"http://www.wikidata.org/entity/Q5460005
">Q5460005
</a
>,
257 <a href=
"http://www.wikidata.org/entity/Q5463392
">Q5463392
</a
>,
258 <a href=
"http://www.wikidata.org/entity/Q3038555
">Q3038555
</a
>,
259 <a href=
"http://www.wikidata.org/entity/Q5288458
">Q5288458
</a
>,
260 <a href=
"http://www.wikidata.org/entity/Q2346516
">Q2346516
</a
>,
261 <a href=
"http://www.wikidata.org/entity/Q5183645
">Q5183645
</a
>,
262 <a href=
"http://www.wikidata.org/entity/Q5185497
">Q5185497
</a
>,
263 <a href=
"http://www.wikidata.org/entity/Q5216127
">Q5216127
</a
>,
264 <a href=
"http://www.wikidata.org/entity/Q5223127
">Q5223127
</a
>,
265 <a href=
"http://www.wikidata.org/entity/Q5261159
">Q5261159
</a
>,
266 <a href=
"http://www.wikidata.org/entity/Q1300759
">Q1300759
</a
>,
267 <a href=
"http://www.wikidata.org/entity/Q5521241
">Q5521241
</a
>,
268 <a href=
"http://www.wikidata.org/entity/Q7733434
">Q7733434
</a
>,
269 <a href=
"http://www.wikidata.org/entity/Q7736264
">Q7736264
</a
>,
270 <a href=
"http://www.wikidata.org/entity/Q7737032
">Q7737032
</a
>,
271 <a href=
"http://www.wikidata.org/entity/Q7882671
">Q7882671
</a
>,
272 <a href=
"http://www.wikidata.org/entity/Q7719427
">Q7719427
</a
>,
273 <a href=
"http://www.wikidata.org/entity/Q7719444
">Q7719444
</a
>,
274 <a href=
"http://www.wikidata.org/entity/Q7722575
">Q7722575
</a
>,
275 <a href=
"http://www.wikidata.org/entity/Q2629763
">Q2629763
</a
>,
276 <a href=
"http://www.wikidata.org/entity/Q2640346
">Q2640346
</a
>,
277 <a href=
"http://www.wikidata.org/entity/Q2649671
">Q2649671
</a
>,
278 <a href=
"http://www.wikidata.org/entity/Q7703851
">Q7703851
</a
>,
279 <a href=
"http://www.wikidata.org/entity/Q7747041
">Q7747041
</a
>,
280 <a href=
"http://www.wikidata.org/entity/Q6544949
">Q6544949
</a
>,
281 <a href=
"http://www.wikidata.org/entity/Q6672759
">Q6672759
</a
>,
282 <a href=
"http://www.wikidata.org/entity/Q2445896
">Q2445896
</a
>,
283 <a href=
"http://www.wikidata.org/entity/Q12124891
">Q12124891
</a
>,
284 <a href=
"http://www.wikidata.org/entity/Q3127044
">Q3127044
</a
>,
285 <a href=
"http://www.wikidata.org/entity/Q2511262
">Q2511262
</a
>,
286 <a href=
"http://www.wikidata.org/entity/Q2517672
">Q2517672
</a
>,
287 <a href=
"http://www.wikidata.org/entity/Q2543165
">Q2543165
</a
>,
288 <a href=
"http://www.wikidata.org/entity/Q426628
">Q426628
</a
>,
289 <a href=
"http://www.wikidata.org/entity/Q426628
">Q426628
</a
>,
290 <a href=
"http://www.wikidata.org/entity/Q12126890
">Q12126890
</a
>,
291 <a href=
"http://www.wikidata.org/entity/Q13359969
">Q13359969
</a
>,
292 <a href=
"http://www.wikidata.org/entity/Q13359969
">Q13359969
</a
>,
293 <a href=
"http://www.wikidata.org/entity/Q2294295
">Q2294295
</a
>,
294 <a href=
"http://www.wikidata.org/entity/Q2294295
">Q2294295
</a
>,
295 <a href=
"http://www.wikidata.org/entity/Q2559509
">Q2559509
</a
>,
296 <a href=
"http://www.wikidata.org/entity/Q2559912
">Q2559912
</a
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297 <a href=
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>
334 <title>A one-way wall on the border?
</title>
335 <link>http://people.skolelinux.org/pere/blog/A_one_way_wall_on_the_border_.html
</link>
336 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/A_one_way_wall_on_the_border_.html
</guid>
337 <pubDate>Sat,
14 Oct
2017 22:
10:
00 +
0200</pubDate>
338 <description><p
>I find it fascinating how many of the people being locked inside
339 the proposed border wall between USA and Mexico support the idea. The
340 proposal to keep Mexicans out reminds me of
341 <a href=
"http://www.history.com/news/
10-things-you-may-not-know-about-the-berlin-wall
">the
342 propaganda twist from the East Germany government
</a
> calling the wall
343 the “Antifascist Bulwark” after erecting the Berlin Wall, claiming
344 that the wall was erected to keep enemies from creeping into East
345 Germany, while it was obvious to the people locked inside it that it
346 was erected to keep the people from escaping.
</p
>
348 <p
>Do the people in USA supporting this wall really believe it is a
349 one way wall, only keeping people on the outside from getting in,
350 while not keeping people in the inside from getting out?
</p
>
355 <title>Generating
3D prints in Debian using Cura and Slic3r(-prusa)
</title>
356 <link>http://people.skolelinux.org/pere/blog/Generating_3D_prints_in_Debian_using_Cura_and_Slic3r__prusa_.html
</link>
357 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Generating_3D_prints_in_Debian_using_Cura_and_Slic3r__prusa_.html
</guid>
358 <pubDate>Mon,
9 Oct
2017 10:
50:
00 +
0200</pubDate>
359 <description><p
>At my nearby maker space,
360 <a href=
"http://sonen.ifi.uio.no/
">Sonen
</a
>, I heard the story that it
361 was easier to generate gcode files for theyr
3D printers (Ultimake
2+)
362 on Windows and MacOS X than Linux, because the software involved had
363 to be manually compiled and set up on Linux while premade packages
364 worked out of the box on Windows and MacOS X. I found this annoying,
365 as the software involved,
366 <a href=
"https://github.com/Ultimaker/Cura
">Cura
</a
>, is free software
367 and should be trivial to get up and running on Linux if someone took
368 the time to package it for the relevant distributions. I even found
369 <a href=
"https://bugs.debian.org/
706656">a request for adding into
370 Debian
</a
> from
2013, which had seem some activity over the years but
371 never resulted in the software showing up in Debian. So a few days
372 ago I offered my help to try to improve the situation.
</p
>
374 <p
>Now I am very happy to see that all the packages required by a
375 working Cura in Debian are uploaded into Debian and waiting in the NEW
376 queue for the ftpmasters to have a look. You can track the progress
378 <a href=
"https://qa.debian.org/developer.php?email=
3dprinter-general%
40lists.alioth.debian.org
">the
379 status page for the
3D printer team
</a
>.
</p
>
381 <p
>The uploaded packages are a bit behind upstream, and was uploaded
382 now to get slots in
<a href=
"https://ftp-master.debian.org/new.html
">the NEW
383 queue
</a
> while we work up updating the packages to the latest
384 upstream version.
</p
>
386 <p
>On a related note, two competitors for Cura, which I found harder
387 to use and was unable to configure correctly for Ultimaker
2+ in the
388 short time I spent on it, are already in Debian. If you are looking
389 for
3D printer
"slicers
" and want something already available in
391 <a href=
"https://tracker.debian.org/pkg/slic3r
">slic3r
</a
> and
392 <a href=
"https://tracker.debian.org/pkg/slic3r-prusa
">slic3r-prusa
</a
>.
393 The latter is a fork of the former.
</p
>
398 <title>Mangler du en skrue, eller har du en skrue løs?
</title>
399 <link>http://people.skolelinux.org/pere/blog/Mangler_du_en_skrue__eller_har_du_en_skrue_l_s_.html
</link>
400 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Mangler_du_en_skrue__eller_har_du_en_skrue_l_s_.html
</guid>
401 <pubDate>Wed,
4 Oct
2017 09:
40:
00 +
0200</pubDate>
402 <description>Når jeg holder på med ulike prosjekter, så trenger jeg stadig ulike
403 skruer. Det siste prosjektet jeg holder på med er å lage
404 <a href=
"https://www.thingiverse.com/thing:
676916">en boks til en
405 HDMI-touch-skjerm
</a
> som skal brukes med Raspberry Pi. Boksen settes
406 sammen med skruer og bolter, og jeg har vært i tvil om hvor jeg kan
407 få tak i de riktige skruene. Clas Ohlson og Jernia i nærheten har
408 sjelden hatt det jeg trenger. Men her om dagen fikk jeg et fantastisk
409 tips for oss som bor i Oslo.
410 <a href=
"http://www.zachskruer.no/
">Zachariassen Jernvare AS
</a
> i
411 <a href=
"http://www.openstreetmap.org/?mlat=
59.93421&mlon=
10.76795#map=
19/
59.93421/
10.76795">Hegermannsgate
412 23A på Torshov
</a
> har et fantastisk utvalg, og åpent mellom
09:
00 og
413 17:
00. De selger skruer, muttere, bolter, skiver etc i løs vekt, og
414 så langt har jeg fått alt jeg har lett etter. De har i tillegg det
415 meste av annen jernvare, som verktøy, lamper, ledninger, etc. Jeg
416 håper de har nok kunder til å holde det gående lenge, da dette er en
417 butikk jeg kommer til å besøke ofte. Butikken er et funn å ha i
418 nabolaget for oss som liker å bygge litt selv. :)
</p
>
423 <title>Visualizing GSM radio chatter using gr-gsm and Hopglass
</title>
424 <link>http://people.skolelinux.org/pere/blog/Visualizing_GSM_radio_chatter_using_gr_gsm_and_Hopglass.html
</link>
425 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Visualizing_GSM_radio_chatter_using_gr_gsm_and_Hopglass.html
</guid>
426 <pubDate>Fri,
29 Sep
2017 10:
30:
00 +
0200</pubDate>
427 <description><p
>Every mobile phone announce its existence over radio to the nearby
428 mobile cell towers. And this radio chatter is available for anyone
429 with a radio receiver capable of receiving them. Details about the
430 mobile phones with very good accuracy is of course collected by the
431 phone companies, but this is not the topic of this blog post. The
432 mobile phone radio chatter make it possible to figure out when a cell
433 phone is nearby, as it include the SIM card ID (IMSI). By paying
434 attention over time, one can see when a phone arrive and when it leave
435 an area. I believe it would be nice to make this information more
436 available to the general public, to make more people aware of how
437 their phones are announcing their whereabouts to anyone that care to
440 <p
>I am very happy to report that we managed to get something
441 visualizing this information up and running for
442 <a href=
"http://norwaymakers.org/osf17
">Oslo Skaperfestival
2017</a
>
443 (Oslo Makers Festival) taking place today and tomorrow at Deichmanske
444 library. The solution is based on the
445 <a href=
"http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html
">simple
446 recipe for listening to GSM chatter
</a
> I posted a few days ago, and
447 will show up at the stand of
<a href=
"http://sonen.ifi.uio.no/
">Åpen
448 Sone from the Computer Science department of the University of
449 Oslo
</a
>. The presentation will show the nearby mobile phones (aka
450 IMSIs) as dots in a web browser graph, with lines to the dot
451 representing mobile base station it is talking to. It was working in
452 the lab yesterday, and was moved into place this morning.
</p
>
454 <p
>We set up a fairly powerful desktop machine using Debian
455 Buster/Testing with several (five, I believe) RTL2838 DVB-T receivers
456 connected and visualize the visible cell phone towers using an
457 <a href=
"https://github.com/marlow925/hopglass
">English version of
458 Hopglass
</a
>. A fairly powerfull machine is needed as the
459 grgsm_livemon_headless processes from
460 <a href=
"https://tracker.debian.org/pkg/gr-gsm
">gr-gsm
</a
> converting
461 the radio signal to data packages is quite CPU intensive.
</p
>
463 <p
>The frequencies to listen to, are identified using a slightly
464 patched scan-and-livemon (to set the --args values for each receiver),
465 and the Hopglass data is generated using the
466 <a href=
"https://github.com/petterreinholdtsen/IMSI-catcher/tree/meshviewer-output
">patches
467 in my meshviewer-output branch
</a
>. For some reason we could not get
468 more than four SDRs working. There is also a geographical map trying
469 to show the location of the base stations, but I believe their
470 coordinates are hardcoded to some random location in Germany, I
471 believe. The code should be replaced with code to look up location in
472 a text file, a sqlite database or one of the online databases
474 <a href=
"https://github.com/Oros42/IMSI-catcher/issues/
14">the github
475 issue for the topic
</a
>.
477 <p
>If this sound interesting, visit the stand at the festival!
</p
>
482 <title>Easier recipe to observe the cell phones around you
</title>
483 <link>http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html
</link>
484 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html
</guid>
485 <pubDate>Sun,
24 Sep
2017 08:
30:
00 +
0200</pubDate>
486 <description><p
>A little more than a month ago I wrote
487 <a href=
"http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html
">how
488 to observe the SIM card ID (aka IMSI number) of mobile phones talking
489 to nearby mobile phone base stations using Debian GNU/Linux and a
490 cheap USB software defined radio
</a
>, and thus being able to pinpoint
491 the location of people and equipment (like cars and trains) with an
492 accuracy of a few kilometer. Since then we have worked to make the
493 procedure even simpler, and it is now possible to do this without any
494 manual frequency tuning and without building your own packages.
</p
>
496 <p
>The
<a href=
"https://tracker.debian.org/pkg/gr-gsm
">gr-gsm
</a
>
497 package is now included in Debian testing and unstable, and the
498 IMSI-catcher code no longer require root access to fetch and decode
499 the GSM data collected using gr-gsm.
</p
>
501 <p
>Here is an updated recipe, using packages built by Debian and a git
502 clone of two python scripts:
</p
>
506 <li
>Start with a Debian machine running the Buster version (aka
509 <li
>Run
'<tt
>apt install gr-gsm python-numpy python-scipy
510 python-scapy
</tt
>' as root to install required packages.
</li
>
512 <li
>Fetch the code decoding GSM packages using
'<tt
>git clone
513 github.com/Oros42/IMSI-catcher.git
</tt
>'.
</li
>
515 <li
>Insert USB software defined radio supported by GNU Radio.
</li
>
517 <li
>Enter the IMSI-catcher directory and run
'<tt
>python
518 scan-and-livemon
</tt
>' to locate the frequency of nearby base
519 stations and start listening for GSM packages on one of them.
</li
>
521 <li
>Enter the IMSI-catcher directory and run
'<tt
>python
522 simple_IMSI-catcher.py
</tt
>' to display the collected information.
</li
>
526 <p
>Note, due to a bug somewhere the scan-and-livemon program (actually
527 <a href=
"https://github.com/ptrkrysik/gr-gsm/issues/
336">its underlying
528 program grgsm_scanner
</a
>) do not work with the HackRF radio. It does
529 work with RTL
8232 and other similar USB radio receivers you can get
531 (
<a href=
"https://www.ebay.com/sch/items/?_nkw=rtl+
2832">for example
532 from ebay
</a
>), so for now the solution is to scan using the RTL radio
533 and only use HackRF for fetching GSM data.
</p
>
535 <p
>As far as I can tell, a cell phone only show up on one of the
536 frequencies at the time, so if you are going to track and count every
537 cell phone around you, you need to listen to all the frequencies used.
538 To listen to several frequencies, use the --numrecv argument to
539 scan-and-livemon to use several receivers. Further, I am not sure if
540 phones using
3G or
4G will show as talking GSM to base stations, so
541 this approach might not see all phones around you. I typically see
542 0-
400 IMSI numbers an hour when looking around where I live.
</p
>
544 <p
>I
've tried to run the scanner on a
545 <a href=
"https://wiki.debian.org/RaspberryPi
">Raspberry Pi
2 and
3
546 running Debian Buster
</a
>, but the grgsm_livemon_headless process seem
547 to be too CPU intensive to keep up. When GNU Radio print
'O
' to
548 stdout, I am told there it is caused by a buffer overflow between the
549 radio and GNU Radio, caused by the program being unable to read the
550 GSM data fast enough. If you see a stream of
'O
's from the terminal
551 where you started scan-and-livemon, you need a give the process more
552 CPU power. Perhaps someone are able to optimize the code to a point
553 where it become possible to set up RPi3 based GSM sniffers? I tried
554 using Raspbian instead of Debian, but there seem to be something wrong
555 with GNU Radio on raspbian, causing glibc to abort().
</p
>
560 <title>Datalagringsdirektivet kaster skygger over Høyre og Arbeiderpartiet
</title>
561 <link>http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_kaster_skygger_over_H_yre_og_Arbeiderpartiet.html
</link>
562 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_kaster_skygger_over_H_yre_og_Arbeiderpartiet.html
</guid>
563 <pubDate>Thu,
7 Sep
2017 21:
35:
00 +
0200</pubDate>
564 <description><p
>For noen dager siden publiserte Jon Wessel-Aas en bloggpost om
565 «
<a href=
"http://www.uhuru.biz/?p=
1821">Konklusjonen om datalagring som
566 EU-kommisjonen ikke ville at vi skulle få se
</a
>». Det er en
567 interessant gjennomgang av EU-domstolens syn på snurpenotovervåkning
568 av befolkningen, som er klar på at det er i strid med
569 EU-lovgivingen.
</p
>
571 <p
>Valgkampen går for fullt i Norge, og om noen få dager er siste
572 frist for å avgi stemme. En ting er sikkert, Høyre og Arbeiderpartiet
574 <a href=
"http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_gj_r_at_Oslo_H_yre_og_Arbeiderparti_ikke_f_r_min_stemme_i__r.html
">denne
575 gangen heller
</a
>. Jeg har ikke glemt at de tvang igjennom loven som
576 skulle pålegge alle data- og teletjenesteleverandører å overvåke alle
577 sine kunder. En lov som er vedtatt, og aldri opphevet igjen.
</p
>
579 <p
>Det er tydelig fra diskusjonen rundt grenseløs digital overvåkning
580 (eller
"Digital Grenseforsvar
" som det kalles i Orvellisk nytale) at
581 hverken Høyre og Arbeiderpartiet har noen prinsipielle sperrer mot å
582 overvåke hele befolkningen, og diskusjonen så langt tyder på at flere
583 av de andre partiene heller ikke har det. Mange av
584 <a href=
"https://data.holderdeord.no/votes/
1301946411e
">de som stemte
585 for Datalagringsdirektivet i Stortinget
</a
> (
64 fra Arbeiderpartiet,
586 25 fra Høyre) er fortsatt aktive og argumenterer fortsatt for å radere
587 vekk mer av innbyggernes privatsfære.
</p
>
589 <p
>Når myndighetene demonstrerer sin mistillit til folket, tror jeg
590 folket selv bør legge litt innsats i å verne sitt privatliv, ved å ta
591 i bruk ende-til-ende-kryptert kommunikasjon med sine kjente og kjære,
592 og begrense hvor mye privat informasjon som deles med uvedkommende.
593 Det er jo ingenting som tyder på at myndighetene kommer til å være vår
595 <a href=
"http://people.skolelinux.org/pere/blog/How_to_talk_with_your_loved_ones_in_private.html
">Det
596 er mange muligheter
</a
>. Selv har jeg litt sans for
597 <a href=
"https://ring.cx/
">Ring
</a
>, som er basert på p2p-teknologi
598 uten sentral kontroll, er fri programvare, og støtter meldinger, tale
599 og video. Systemet er tilgjengelig ut av boksen fra
600 <a href=
"https://tracker.debian.org/pkg/ring
">Debian
</a
> og
601 <a href=
"https://launchpad.net/ubuntu/+source/ring
">Ubuntu
</a
>, og det
602 finnes pakker for Android, MacOSX og Windows. Foreløpig er det få
603 brukere med Ring, slik at jeg også bruker
604 <a href=
"https://signal.org/
">Signal
</a
> som nettleserutvidelse.
</p
>
609 <title>Simpler recipe on how to make a simple $
7 IMSI Catcher using Debian
</title>
610 <link>http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html
</link>
611 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html
</guid>
612 <pubDate>Wed,
9 Aug
2017 23:
59:
00 +
0200</pubDate>
613 <description><p
>On friday, I came across an interesting article in the Norwegian
614 web based ICT news magazine digi.no on
615 <a href=
"https://www.digi.no/artikler/sikkerhetsforsker-lagde-enkel-imsi-catcher-for-
60-kroner-na-kan-mobiler-kartlegges-av-alle/
398588">how
616 to collect the IMSI numbers of nearby cell phones
</a
> using the cheap
617 DVB-T software defined radios. The article refered to instructions
618 and
<a href=
"https://www.youtube.com/watch?v=UjwgNd_as30
">a recipe by
619 Keld Norman on Youtube on how to make a simple $
7 IMSI Catcher
</a
>, and I decided to test them out.
</p
>
621 <p
>The instructions said to use Ubuntu, install pip using apt (to
622 bypass apt), use pip to install pybombs (to bypass both apt and pip),
623 and the ask pybombs to fetch and build everything you need from
624 scratch. I wanted to see if I could do the same on the most recent
625 Debian packages, but this did not work because pybombs tried to build
626 stuff that no longer build with the most recent openssl library or
627 some other version skew problem. While trying to get this recipe
628 working, I learned that the apt-
>pip-
>pybombs route was a long detour,
629 and the only piece of software dependency missing in Debian was the
630 gr-gsm package. I also found out that the lead upstream developer of
631 gr-gsm (the name stand for GNU Radio GSM) project already had a set of
632 Debian packages provided in an Ubuntu PPA repository. All I needed to
633 do was to dget the Debian source package and built it.
</p
>
635 <p
>The IMSI collector is a python script listening for packages on the
636 loopback network device and printing to the terminal some specific GSM
637 packages with IMSI numbers in them. The code is fairly short and easy
638 to understand. The reason this work is because gr-gsm include a tool
639 to read GSM data from a software defined radio like a DVB-T USB stick
640 and other software defined radios, decode them and inject them into a
641 network device on your Linux machine (using the loopback device by
642 default). This proved to work just fine, and I
've been testing the
643 collector for a few days now.
</p
>
645 <p
>The updated and simpler recipe is thus to
</p
>
649 <li
>start with a Debian machine running Stretch or newer,
</li
>
651 <li
>build and install the gr-gsm package available from
652 <a href=
"http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/
">http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/
</a
>,
</li
>
654 <li
>clone the git repostory from
<a href=
"https://github.com/Oros42/IMSI-catcher
">https://github.com/Oros42/IMSI-catcher
</a
>,
</li
>
656 <li
>run grgsm_livemon and adjust the frequency until the terminal
657 where it was started is filled with a stream of text (meaning you
658 found a GSM station).
</li
>
660 <li
>go into the IMSI-catcher directory and run
'sudo python simple_IMSI-catcher.py
' to extract the IMSI numbers.
</li
>
664 <p
>To make it even easier in the future to get this sniffer up and
665 running, I decided to package
666 <a href=
"https://github.com/ptrkrysik/gr-gsm/
">the gr-gsm project
</a
>
667 for Debian (
<a href=
"https://bugs.debian.org/
871055">WNPP
668 #
871055</a
>), and the package was uploaded into the NEW queue today.
669 Luckily the gnuradio maintainer has promised to help me, as I do not
670 know much about gnuradio stuff yet.
</p
>
672 <p
>I doubt this
"IMSI cacher
" is anywhere near as powerfull as
673 commercial tools like
674 <a href=
"https://www.thespyphone.com/portable-imsi-imei-catcher/
">The
675 Spy Phone Portable IMSI / IMEI Catcher
</a
> or the
676 <a href=
"https://en.wikipedia.org/wiki/Stingray_phone_tracker
">Harris
677 Stingray
</a
>, but I hope the existance of cheap alternatives can make
678 more people realise how their whereabouts when carrying a cell phone
679 is easily tracked. Seeing the data flow on the screen, realizing that
680 I live close to a police station and knowing that the police is also
681 wearing cell phones, I wonder how hard it would be for criminals to
682 track the position of the police officers to discover when there are
683 police near by, or for foreign military forces to track the location
684 of the Norwegian military forces, or for anyone to track the location
685 of government officials...
</p
>
687 <p
>It is worth noting that the data reported by the IMSI-catcher
688 script mentioned above is only a fraction of the data broadcasted on
689 the GSM network. It will only collect one frequency at the time,
690 while a typical phone will be using several frequencies, and not all
691 phones will be using the frequencies tracked by the grgsm_livemod
692 program. Also, there is a lot of radio chatter being ignored by the
693 simple_IMSI-catcher script, which would be collected by extending the
694 parser code. I wonder if gr-gsm can be set up to listen to more than
695 one frequency?
</p
>
700 <title>Norwegian Bokmål edition of Debian Administrator
's Handbook is now available
</title>
701 <link>http://people.skolelinux.org/pere/blog/Norwegian_Bokm_l_edition_of_Debian_Administrator_s_Handbook_is_now_available.html
</link>
702 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Norwegian_Bokm_l_edition_of_Debian_Administrator_s_Handbook_is_now_available.html
</guid>
703 <pubDate>Tue,
25 Jul
2017 21:
10:
00 +
0200</pubDate>
704 <description><p align=
"center
"><img align=
"center
" src=
"http://people.skolelinux.org/pere/blog/images/
2017-
07-
25-debian-handbook-nb-testprint.png
"/
></p
>
706 <p
>I finally received a copy of the Norwegian Bokmål edition of
707 "<a href=
"https://debian-handbook.info/
">The Debian Administrator
's
708 Handbook
</a
>". This test copy arrived in the mail a few days ago, and
709 I am very happy to hold the result in my hand. We spent around one and a half year translating it. This paperbook edition
710 <a href=
"https://debian-handbook.info/get/#norwegian
">is available
711 from lulu.com
</a
>. If you buy it quickly, you save
25% on the list
712 price. The book is also available for download in electronic form as
713 PDF, EPUB and Mobipocket, as can be
714 <a href=
"https://debian-handbook.info/browse/nb-NO/stable/
">read online
715 as a web page
</a
>.
</p
>
717 <p
>This is the second book I publish (the first was the book
718 "<a href=
"http://free-culture.cc/
">Free Culture
</a
>" by Lawrence Lessig
720 <a href=
"http://www.lulu.com/shop/lawrence-lessig/free-culture/paperback/product-
22440520.html
">English
</a
>,
721 <a href=
"http://www.lulu.com/shop/lawrence-lessig/culture-libre/paperback/product-
22645082.html
">French
</a
>
723 <a href=
"http://www.lulu.com/shop/lawrence-lessig/fri-kultur/paperback/product-
22441576.html
">Norwegian
724 Bokmål
</a
>), and I am very excited to finally wrap up this
726 "<a href=
"http://www.lulu.com/shop/rapha%C3%ABl-hertzog-and-roland-mas/h%C3%A5ndbok-for-debian-administratoren/paperback/product-
23262290.html
">Håndbok
727 for Debian-administratoren
</a
>" will be well received.
</p
>