Flipped images from your webcam in Ubuntu?

echo -e "\n# libv4l PPA\ndeb http://ppa.launchpad.net/libv4l/ppa/ubuntu `lsb_release -c | awk '{print $2}'` main" | sudo tee -a /etc/apt/sources.list
sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com C3FFB4AA
sudo apt-get update
sudo apt-get install libv4l-0

LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so application_name

114 Comments

• 
  Alchemist November 13th, 2009 at 03:51

  Perfect.

  I’ve struggled with this for so long. None of the kernel patches worked (and I really don’t like patching my kernel)

  This has worked like charm (Asus B50A, Ubuntu 9.10, KDE)

  Thanks a mighty lot, from Nairobi, Kenya.

  Reply
• 
  TataLor November 14th, 2009 at 21:15

  Hello,

  Thanks for the solution!
  Works on Asus N50vc.

  Reply
• 
  Alchemist November 14th, 2009 at 21:51

  Wait! After a restart it’s upside down again!

  Reply
• 
  Radu

  November 14th, 2009 at 22:19

  @Alchemist: I forgot to add the line regarding the LD_PRELOAD variable. It should work now.

  Reply
• 
  vacant79 November 17th, 2009 at 02:01

  this doesn’t seem to work for me (i cut and past the four commands as you have them into terminal, but the cam is still flipped).. i have a n10e (running karmic)…

  so i guess i should check with hans whether the cam is in his library… but i’m not sure how to get the info he needs from the 2 files (sorry, i’m still new at all this linux stuff).. on the site you link to he says:

  If you have such a laptop can you please mail the output of the following commands:
  lsusb > lsusb.log
  dmidecode > dmi.log

  …when i type those two commands (as written there) into terminal, nothing happens… am i supposed to add something to those commands to make something happen?

  thanks

  Reply
  • 
    Radu

    November 17th, 2009 at 02:18

    When you ran those commands, their output was written in those two files (lsusb.log and dmi.log). The files can be found in the folder where you have run the commands (if you just opened a terminal, that folder should be your home directory).

    Reply
• 
  vacant79 November 17th, 2009 at 02:24

  excellent, they are, thanks.

  Reply
• 
  Christian November 18th, 2009 at 02:07

  I copypasted everything – it didn’t work (ASUS X5DIJ, Karmic Koala). Then I checked the preloader of Hans’ webpage. It is shorter:

  LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so skype

  (in the case of Skype)

  No it works perfectly. Thank you very much!

  Reply
• 
  vacant79 November 18th, 2009 at 14:11

  it also works for me now (on my n10e) with the shorter pre-loader mentioned in the christian’s post above (i also first sent the two files to hans, who then i think updated the library)… and as with the post above, i do need to use the preloader to get the webcam flipped right way up for skype.

  radu, you mention a ‘more elegant solution’ to using terminal to launch…. i was hoping i could just put LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so skype into the command line in skype (properties) under main menu (admittedy, i don’t really know what i am doing)… but that does not seem to work…i don’t suppose you could tell me how to do it.
  thanks.

  Reply
• 
  Radu

  November 18th, 2009 at 14:20

  You can make a Skype wrapper script like this:

  #!/bin/bash
  LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so skype
  exit 0
  

  which could be saved in ~/bin/skypeWrapper.sh, as this folder is automatically added to the PATH variable. Remeber to make the script executable. Then, for the Skype launcher in the main menu use this wrapper script.

  Reply
• 
  Radu

  November 18th, 2009 at 14:29

  Or better yet… Make a general wrapper for all webcam applications similar to the one above:

  #!/bin/bash
  LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so $1
  exit 0
  

  Save the script in ~/bin/webcamWrapper.sh, make it executable and then for each application that needs the library loaded in its menu entry, for the command field, write something like

  webcamWrapper.sh application_name
  

  Reply
  • 
    korso19 February 15th, 2011 at 11:59

    Hello,

    I ‘ve looked for the file bin/webcamWrapper.sh but cannot find it……do I have to create it? any help would be greatly appreciated. One more question. if I follow the instructions of adding the repository and then installing lib4vl, do I still need to create the wrapper file to get skype running properly? I ask because I’ve tried running skype with the following command

    LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so

    in the terminal, this is the output I get

    ERROR: ld.so: object ‘/usr/lib32/libv4l/v4l1compat.so’ from LD_PRELOAD cannot be preloaded: ignored.

    I’ve tried reading this article by Hans http://hansdegoede.livejournal.com/7622.html but haven’t understood head or tail of it!

    One more thing, I do know that I’m running a 64 bit computer and that the instructions over here are for 32 bit PCs am I right! Help!!! I’m lost!

    Thanks for any eventual reply and help.

    Reply
    • 
      Radu

      February 16th, 2011 at 23:42

      You’d have to copy the exact code from the post into a file and make it executable in order to generate the wrapper script. Regarding the error, you might need to use the 64-bit version of the library for the applications you run. To find out what system you have open a terminal and type this:

      uname -m
      
    • 
      elvis_ef September 17th, 2011 at 16:08

      korso19, firstly, install the ld.so.preload-manager to get your script run correctly.

    [language]
    code lines
    [/language]
	

    [bash]
    /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
    [/bash]
	

    The <code>$USER</code> variable holds the current logged in username.