blog/Recording_video_from_cron_using_VLC.html

   1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
   2         "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
   3 <html>
   4  <head>
   5   <title>Petter Reinholdtsen: Recording video from cron using VLC</title>
   6   <link rel="stylesheet" type="text/css" media="screen" href="http://people.skolelinux.org/pere/blog/style.css">
   7  </head>
   8  <body>
   9
  10  <div class="title">
  11   <h1>
  12        <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  13
  14   </h1>
  15
  16  </div>
  17
  18
  19  <div class="entry">
  20   <div class="title">Recording video from cron using VLC</div>
  21   <div class="date">2009-04-05 10:00</div>
  22   <div class="body">
  23 <p>One think I have wanted to figure out for a along time is how to
  24 run vlc from cron to do recording of video streams on the net.  The
  25 task is trivial with mplayer, but I do not really trust the security
  26 of mplayer (it crashes too often on strange input), and thus prefer
  27 vlc.  I finally found a way to do it today.  I spent an hour or so
  28 searching the web for recipes and reading the documentation.  The
  29 hardest part was to get rid of the GUI window, but after finding the
  30 dummy interface, the command line finally presented itself:</p>
  31
  32 <blockquote><pre>URL=http://www.ping.uio.no/video/rms-oslo_2009.ogg
  33 SAVEFILE=rms.ogg
  34 DISPLAY= vlc -q $URL \
  35   --sout="#duplicate{dst=std{access=file,url='$SAVEFILE'},dst=nodisplay}" \
  36   --intf=dummy</pre></blockquote>
  37
  38 <p>The command stream the URL and store it in the SAVEFILE by
  39 duplicating the output stream to "nodisplay" and the file, using the
  40 dummy interface.  The dummy interface and the nodisplay output make
  41 sure no X interface is needed.</p>
  42
  43 <p>The cron job then need to start this job with the appropriate URL
  44 and file name to save, sleep for the duration wanted, and then kill
  45 the vlc process with SIGTERM.  Here is a complete script
  46 <tt>vlc-record</tt> to use from <tt>at</tt> or <tt>cron</tt>:</p>
  47
  48 <blockquote><pre>#!/bin/sh
  49 set -e
  50 URL="$1"
  51 SAVEFILE="$2"
  52 DURATION="$3"
  53 DISPLAY= vlc -q "$URL" \
  54   --sout="#duplicate{dst=std{access=file,url='$SAVEFILE'},dst=nodisplay}" \
  55   --intf=dummy < /dev/null > /dev/null 2>&1 &
  56 pid=$!
  57 sleep $DURATION
  58 kill $pid
  59 wait $pid</pre></blockquote>
  60 </div>
  61
  62   <div class="tags">Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>, <a href="http://people.skolelinux.org/pere/blog/tags/video">video</a>.</div>
  63
  64   </div>
  65
  66
  67
  68
  69
  70
  71 <div id="sidebar">
  72
  73 <h2>Archive</h2>
  74 <ul>
  75
  76 <li>2010
  77 <ul>
  78
  79 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
  80
  81 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
  82
  83 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
  84
  85 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
  86
  87 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
  88
  89 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
  90
  91 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
  92
  93 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
  94
  95 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
  96
  97 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
  98
  99 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (10)</a></li>
 100
 101 </ul></li>
 102
 103 <li>2009
 104 <ul>
 105
 106 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 107
 108 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 109
 110 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 111
 112 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 113
 114 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 115
 116 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 117
 118 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 119
 120 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 121
 122 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 123
 124 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 125
 126 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 127
 128 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 129
 130 </ul></li>
 131
 132 <li>2008
 133 <ul>
 134
 135 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 136
 137 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 138
 139 </ul></li>
 140
 141 </ul>
 142
 143
 144
 145 <h2>Tags</h2>
 146 <ul>
 147
 148  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (12)</a></li>
 149
 150  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 151
 152  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 153
 154  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (10)</a></li>
 155
 156  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (42)</a></li>
 157
 158  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (50)</a></li>
 159
 160  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (71)</a></li>
 161
 162  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (1)</a></li>
 163
 164  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (11)</a></li>
 165
 166  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (5)</a></li>
 167
 168  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (8)</a></li>
 169
 170  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (4)</a></li>
 171
 172  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 173
 174  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (10)</a></li>
 175
 176  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (90)</a></li>
 177
 178  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (113)</a></li>
 179
 180  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (18)</a></li>
 181
 182  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (25)</a></li>
 183
 184  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (10)</a></li>
 185
 186  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (4)</a></li>
 187
 188  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 189
 190  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (18)</a></li>
 191
 192  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (3)</a></li>
 193
 194  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (16)</a></li>
 195
 196  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (1)</a></li>
 197
 198  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (15)</a></li>
 199
 200  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (1)</a></li>
 201
 202  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (13)</a></li>
 203
 204 </ul>
 205
 206 </div>
 207  </body>
 208 </html>