{"id":991,"date":"2009-10-21T21:51:53","date_gmt":"2009-10-21T21:51:53","guid":{"rendered":"http:\/\/dalelane.co.uk\/blog\/?p=991"},"modified":"2009-10-21T21:51:53","modified_gmt":"2009-10-21T21:51:53","slug":"tracking-my-location-on-tv","status":"publish","type":"post","link":"https:\/\/dalelane.co.uk\/blog\/?p=991","title":{"rendered":"Tracking my location on TV"},"content":{"rendered":"

\"Location<\/a><\/p>\n

This is what you see if you press the “Find Dale” button on my TV remote control. <\/p>\n

(Well, actually the “Teletext” button… cos I wasn’t using it, and there isn’t another button that makes any more sense!<\/em>)<\/p>\n

The on-screen-display adds a message at the bottom of the screen for a few seconds, saying my last recorded location and when I was there. <\/p>\n

People following me on twitter<\/a> may have noticed me talking about setting up a new home media server: a small Linux server that has become our Freeview box, PVR<\/a>, home photo album, and music server. <\/p>\n

And now it’s set up, it is surprisingly easy to do amazingly useful, and not-at-all annoying things like this! \ud83d\ude09<\/p>\n

In my defence, I stopped just short of making the script poll for my location and display an on-screen message whenever my location changes. Which would’ve been very cool, but probably drive my family nuts. So I compromised with a script that runs when you press a button on the remote.<\/em><\/p>\n

There are three bits to this:<\/p>\n

    \n
  1. Getting my location\n<\/li>\n
  2. Putting my location on the TV screen\n<\/li>\n
  3. Getting this to happen when you press a button on the remote\n<\/li>\n<\/ol>\n

    Getting my location<\/strong><\/p>\n

    I use the Google Latitude badge<\/a> that I embed in my blog<\/a> to share my Latitude location, and scrape it to get my location information. <\/p>\n

    Bit of a cludgy and brittle hack, but this will do for my needs.<\/p>\n

    Putting my location on the TV screen<\/strong><\/p>\n

    I’m using VDR<\/a> as the base for our media server. (I was originally gonna use MythTV because I’d heard of it before, but Dom pointed me<\/a> at VDR instead<\/a>). <\/p>\n

    One of the things it supports is svdrp<\/a> – basically it listens on port 2001 for commands. You can send it commands to do anything<\/a>, such as change channels. <\/p>\n

    One of the svdrp commands is MESG<\/code>:<\/p>\n

    Displays the given message on the OSD. If message is omitted, the currently pending message (if any) will be returned. The message will be displayed for a few seconds as soon as the OSD has become idle. If a new MESG command is entered while the previous message has not yet been displayed, the old message will be overwritten.<\/p><\/blockquote>\n

    .
    \nRunning:<\/p>\n

    svdrpsend MESG \"Hello World\"<\/pre>\n
    will display “Hello World” on your TV.<\/p>\n
    And so running:<\/p>\n
    svdrpsend MESG `python \/home\/dale\/scripts\/googlatitude.py`<\/pre>\n
    displays the output of my Python script (which is what downloads the contents of my Latitude embed page, scrapes the text description of my location and prints it to stdout). <\/p>\n
    Running this command displays my location on the TV. <\/p>\n
    Getting this to happen when you press a button on the remote<\/strong><\/p>\n
    The last bit is getting this command to run from the remote control. <\/p>\n
    The vdr installer also installed LIRC<\/a> which handles decoding instructions from my infra-red remote control. <\/p>\n
    As a result, I already had a lircd<\/code> daemon running, and the runvdr script that starts vdr uses the --lirc<\/code> switch to enable lirc support.<\/p>\n
    The file \/var\/lib\/vdr\/remote.conf<\/code> maps buttons on the physical remote (identified in \/etc\/lirc\/lircd.conf<\/code>) to functions in VDR. I chose one of the buttons not used by VDR (and not mentioned in \/var\/lib\/vdr\/remote.conf<\/code>) – “Teletext”. <\/p>\n
    I use irexec<\/a> to use the remote to run other non-VDR commands. <\/p>\n
    Firstly, I create the file ~\/.lircrc<\/code> with the following:<\/p>\n
    begin\r\n   button = Teletext\r\n   prog = irexec\r\n   config = svdrpsend mesg `python \/home\/dale\/scripts\/googlatitude.py` &\r\n   flags = quit\r\nend<\/pre>\n
    Then I start the irexec daemon<\/a> with irexec --daemon<\/code>. This does the job of running my command when the Teletext button is pressed. <\/p>\n
    Job done – location tracking on telly. \ud83d\ude42<\/p>\n","protected":false},"excerpt":{"rendered":"
    This is what you see if you press the “Find Dale” button on my TV remote control. (Well, actually the “Teletext” button… cos I wasn’t using it, and there isn’t another button that makes any more sense!) The on-screen-display adds a message at the bottom of the screen for a few seconds, saying my last […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[158,387,137,428,306,398,427],"class_list":["post-991","post","type-post","status-publish","format-standard","hentry","category-code","tag-google","tag-latitude","tag-location","tag-svdrp","tag-television","tag-tv","tag-vdr"],"_links":{"self":[{"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/posts\/991","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=991"}],"version-history":[{"count":0,"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/posts\/991\/revisions"}],"wp:attachment":[{"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=991"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=991"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dalelane.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=991"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}