Posts Tagged ‘web camera’

How to fix Skype no (built in) web camera on MacBook Air with (Mac OS X 10.8.5) resolve Skype issue of Aug 2013

Sunday, September 29th, 2013

Reading Time: 2minutes

Resolve fix issue with no camera in MacBookAir

My dear fiance girlfriend Svetlana, has a MacBookAir from 2013 since a month time. We speak quite regularly in Skype since right now she is in Belarus and I'm in Bulgaria. So it was a big surprise for me today her brand new shiny MacBookAir camera stopped working. She is completely new to Mac OS X so she didn't have idea if something automatically updated on the notebook, probably some update poped up and she proceeded to update. Well no matter how the issue happened … I instructed her how to install TeamViewer (for Mac OS X – just download the .DMG double click it and install) and logged in to the PC to check what's happening. In FaceTime video was showing fine so obviously on OS level webcamera was detected. I saw some threads suggesting sometimes built in webcam is not working due to some other application which uses the camera (Safari instrance using flash to open webcam, FacePalm or whatever) …
I checked the version release of Mac OS X and it showed Mac OS X 10.8.5. I checked whether some updates are available but there were none. After browsing a bit figured out the web camera not detected Skype error is experienced by hundreds of MacBook air users online. Thanksfully there is a quick and simple fix by just substituting a file called AppleCamera.plugin.

Below are instructions on how to fix I followed from Skype's Community Website: 
———————

This is a very simple fix that works! There are lots of ways to do it, but to put it very simply ,

Download  the AppleCamera.plugin provided.
 

Click on go in the finder menu, select go to golder and paste in  /Library/CoreMediaIO/Plug-Ins/DAL/ ,

 

move that item, AppleCamera.plugin, to the trash

 

Go to your downloads folder and copy the new  AppleCamera.plugin, then paste it in the folder where the old one was. 

 

It works

After following literally instructions Skype camera worked out like a charm 😉

Linux webcam take pictures from tty console or terminal / How to make pictures of yourself using plain console and web-camera

Saturday, December 15th, 2012

Reading Time: 7minutes

how to take webCAM console / terminal pictures on gnu linux (Debian, Ubuntu, Fedora)

I'm a great command line enthusiast, I share the believe of many other command line geeks thinking keyboard is the quickest way to access a computer. Historically keys were first and mouse second and I think there is definitely a good reason for that. Thus today I was curious if it is possible to take pictures from my external web-camera on my Debian GNU / Linux? I did a quick research and this little article springed out as result.

The answer is YES! It is possible and besides that there are many ways to take a webcamera picture using the console; Lastly it is very easy to achieve even for novice Linux buddies 😉 My little research on the topic show me there are 4 straightforward ways one can use to use his extended or embedded WebCam to take pictuers – using (vlc, mplayer, camshot, fswebcam and ffmpeg).

1. Taking a webcam picture using vlc

Invoke vlc with following arguments:

# vlc -I dummy v4l2:///dev/video0 --video-filter scene --no-audio --scene-path /home/hipo --scene-prefix webcam-taken-picture-prefix --scene-format png vlc://quit --run-time=1

I've prepared a little wrapper script, for the sake of simplifying the long and hard to remember vlc options. Below is the script;

#!/bin/sh
# This little script will take picture whilst in gnome-terminal / mlterm or any console tty
# As program uses vlc you need to have vlc properly configured and installed
# as well as the webcam video be properly working (detected by Linux kernel)
# licensed under GPLv2 script modified by hip0 14.12.2012
# Path where to store taken snapshots
STORE_PATH=/home/hipo
# Device locatation of webcam many webcams have default device in /dev/video0
WEBCAM_DEV=/dev/video0
# Stored grabbed picture filename prefix
FILE_NAME_PREF=image_prefix
# gets the current date and adds to set filename prefix
date_cur=$(date +%k_%d_%m_%Y|sed -e 's/^ *//');
vlc -I dummy v4l2://$WEBCAM_DEV --video-filter scene --no-audio --scene-path $STORE_PATH --scene-prefix $FILE_NAME_PREF.$date_cur --scene-format png vlc://quit --run-time=1
echo "WebCam picture taken and stored in $STORE_PATH/$FILE_NAME_PREF.$date_cur*.png";
echo '';
echo "To view picture in Gnome with Eye of GNOME type: eog $STORE_PATH/$FILE_NAME_PREF.$date_cur*.png";

You can also download copy of the webcam_take_picture_from_console.sh script here.

As you see the script uses, vlc's (dummy interface), and –video-filter-scene option to make the snapshot. The script can be stored in let's say /usr/local/bin/webcam_take_picture.sh and aliased through ~/.bashrc with some short alias, i.e.:

alias console-picture='/usr/local/bin/webcam_take_picture.sh'

Then at any time, when you run console-picture you will have a short way to make pictures of your room, your friends or whatever needed. One good application of script is whether you're in coffee with friends and you want to take a snapshot of them without them realizing (assuming, the webcam is embedded) 🙂

Another great application is whether you want to take a snapshot of the WebCam, from another shell script or little application using dialog ncurses interfaces etc.

Even just for the sake of fun it is so nice to take a picture from webcam, whether in plain tty console bash shell 🙂

One small note to make here is webcam_take_picture_from_console.sh should be run as non-root user (for security reasons vlc developers made smartly VLC this way), running it as root drops an err:

>VLC is not supposed to be run as root. Sorry.
If you need to use real-time priorities and/or privileged TCP ports
you can use /usr/bin/vlc-wrapper (make sure it is Set-UID root and
cannot be run by non-trusted users first).
 

By default, vlc resolution used is the automatically set to the maximum supported to the camera, with mine this is 640×480 SRGB
The quality of pictures taken is a bit low but my camera is a cheap one and even with some GUI program snapshot taking programs like GNOME's cheese, taken pictures are with low quality (though I think the brightnes of the ones taken with vlc is a bit poorer than the ones done with cheese).

Happily it is possible to correct picture brightness and lightning with v42l-ctl (v42l-ctl is not installed by default and on Debian you will have to install deb pack v4l-utils), e.g.:

apt-get install --yes v4l-utils
....

Further, check out the possible options available with:

v4l2-ctl -L - (list all possible options)

and to set a concrete option do:

v4l2-ctl -c <options>=<value> (set an option)
 

I don't have a BSD (FreeBSD, NetBSD, OpenBSD) at hand, but with a working supported Webcam, correct location to the webcam /dev/  and installed VLC from ports :

vlc -I dummy v4l2:///dev/video0--video-filter scene --no-audio --scene-path $STORE_PATH --scene-prefix $FILE_NAME_PREF.$date_cur --scene-format png vlc://quit --run-time=1

should be working fine as well.
If someone has access to a BSD with a working installed webcam, please test it and drop a comment to confirm if working …

2. Creating pictures from WebCamera using mplayer cmd

Theoretically mplayer, should be able to take snapshots from the Cam with:

mplayer -vo png -frames 1 tv://

There is possibility to pass output webcam picture (resolution) dimensions too:

mplayer tv:// -tv driver=v4l:device=/dev/video0:width=320:height=240:outfmt=rgb24 -frames 1 -vo jpeg

 

With my "NoName" (Eltron Technology) webcam the produced images were filled up with solid green color  (maybe due to bug of my webcam used driver). Normally it should be working; I've seen many posts around claiming using both of above cmd lines to produce pictures normally, but not for me.

3. Making pictures with WebCamera (camshot) console tool

I've seen around also another tiny tool (camshot) especially written to take pictures from webcam. The tool is available only to be compiled from source (whether source is fetched through Subversion repo (SVN)). I took a minute to test it as well, e.g.:

 

hipo@noah:~Desktop$ svn checkout http://camshot.googlecode.com/svn/trunk/ camshot-read-only

hipo@noah:~/Desktop/camshot-read-only$ make
....
hipo@noah:~/Desktop/camshot-read-only$ ls
arguments.c  arguments.o  camera.h  camshot  image.h  main.c  Makefile  shmem.h  shmem_test.c
arguments.h  camera.c     camera.o  image.c  image.o  main.o  shmem.c   shmem.o

hipo@noah:~Desktop/camshot-read-only$ ./camshot
Letting the camera automaticaly adjust the picture:..........Done.
Command (h for help): h

Commands:
    x    Capture a picture from camera.
    h    Prints this help.
    q    Quits the program.

Command (h for help): x
Command (h for help): q

 

Don't know why, but for me camshot did not produce, any output picture from webcam. Maybe my Webcam which is a cheap (all OS) compatible one is not detected fine by the tool? As you see from above help output there are not many options so it is definitely something with webcam detection or just it needs some kind of little "hack" in the source to make it working, I was lazy to further investigate so I leave it.

4. Making pictures from terminal using fswebcam

fswebcam is not so popular as vlc and mplayer, but is existent from default repostiries on both Debian and Ubuntu Linuces. Here is it how it is described when pkg info requested with apt-cache:

apt-cache show fswebcam | grep -i descrip -A 8
Description: Tiny and flexible webcam program
 Fswebcam is a tiny and flexible webcam command-line program for capturing
 images from a V4L1/V4L2 device. It accepts a number of formats, can skip
 the first (possibly bad) frames before performing the actual capture, and
 can perform simple manipulation on the captured image, such as resizing,
 averaging multiple frames or overlaying a caption or an image.
Homepage: http://www.firestorm.cx/fswebcam/
Tag: implemented-in::c, role::program

To use it first install it with apt-get or yum (yes it is available also for RedHat based Linux distros via yum).
Depending whether on Debian or Fedora etc. do:

apt-get install --yes fswebcam
.....

or

yum -y install fswebcam
....

fswebcam's syntax is much easier than all of rest cmd tools available around; to create picture from webcam;

# fswebcam -r 640x480 --jpeg 85 -D 1 web-cam-shot.jpg
--- Opening /dev/video0...
Trying source module v4l2...
/dev/video0 opened.
No input was specified, using the first.
Delaying 1 seconds.
--- Capturing frame...
Captured frame in 0.00 seconds.
--- Processing captured image...
Setting output format to JPEG, quality 85
Unable to load font 'luxisr': Could not find/open font
Disabling the the banner.
Writing JPEG image to 'web-cam-shot.jpg'.

I liked supports, saving in multiple formats, can set resolution and is probably the number 1 choice for anyone looking for high level of customization of cam taken picture.. Saying this I think fswebcam is definitely the tool of choice as it is written with the one and only aim to take webcam pictures from console.

5. Capturing picture from Webcam using ffmpeg

With ffmpeg, there are plenty of things possible;
Just to mention few interesting ones, I've written about earlier, ffmeg is capable of;

convert .OGG vorbis to MP3 
convert .FLV to .AVI and .AVI to .FLV
convert .AVI .MP4 and .FLV to OGG Vorbis (Free Format)
convert .OGG video to .FLV Video
extract sounds / music from .FLV to a MP3 / MP4
Add .SRT and .SUB files subtitles to Flash Videos

Along with all this, interestingly ffmpeg can get content using command line from WebCamera (nomatter if it's a VIDEO stream or just a Picture snapshot).

The syntax to take a picture with it is:

ffmpeg -f video4linux2 -i /dev/v4l/by-id/usb-Etron_Technology__Inc._USB2.0_Camera-video-index0 -vframes 1 output-picture.jpeg

The precise /dev/(v4l – video 4 linux) assigned to different cameras will differ so in order to find what kind of /dev, to use ls it:

# ls -al /dev/v4l/by-id/*

lrwxrwxrwx 1 root root 12 Dec 14 22:40 /dev/v4l/by-id/usb-Etron_Technology__Inc._USB2.0_Camera-video-index0 -> ../../video0

The picture resolution taken on my Eltron Technology Webcam is same like with vlc – the cam optimum 640×480, the quality and brightness gamma is also identical to pics taken using VLC.
 
Therefore if you're wondering if one tool, might make a better pictures from command line than the other the answer, according to my tests is they produce identical quality and all can be customized easily for different set of resolution. It is possible thought, this is not so with other Web Cam models, if you happen to read this post and take the time to try taking pictures with 5 methods and some of the 5 progs is making superior pictures, please drop a comment with the tool you used and the WebCam exact version as detected in dmesg or lsusb

As a sort of Outtro, from purely functional / usability point of view I think fswebcam is probably be the tool of choice for mostly all as it is most simple, easily customizable and especially crafted for creating webcam console shots. That's all Enjoy, taking pics from GUI terminal or console 🙂 

P.S. – I know there are plenty of people who have written on the topic, so this article is nothing new under the sun, but as I couldn't find a post synthesizing in one all of the 5 methods I've come up with this little article. Feedback is mostly welcome
Happy picturing 😉

How to fix upside-down / inverted web camera laptop Asus K51AC issue on Ubuntu Linux and Debian GNU / Linux

Monday, February 13th, 2012

Reading Time: 4minutes

Skype Video Inverted bat like linux screenshot

Does your camera show video correctly in cheese but shows captured video upside-down (inverted) in skype ?
This is an issue a friend of mine experienced on his Asus K51AC-SX037D laptop on both Ubuntu and Debian Linux.
As you can see in the picture above it is funny as with this bug the person looks like a batman 😉
As the webcam upside-down issue was present on both latest Ubuntu 11.10 and latest stable Debian Squeeze 6.02, my guess was other GNU / Linux rpm based distro like Fedora might have applied a fix to this weird Skype inverted video (bat human like) issue.
Unfortunately testing the webcam with Skype on latest both Fedora 16 and Linux Mint 12 appeared to produce the same webcam bug.

A bit of research for the issue online and try outs of a number of suggested methods to resolve the issue led finally to a work around, thanks to this post
Here is few steps to follow to make the webcam show video like it should:

1. Install libv4l-0 package

root@linux:~# apt-get --yes install libv4-0
...

Onwards to start skype directly from terminal and test the camera type:

hipo@linux:~$ LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so skype

This is the work around for 32 bit Linux install, most people however will probably have installed 64 bit Linux, for 64bit Linux installs the above command should be little different:

hipo@linux:~$ LD_PRELOAD=/usr/lib32/libv4l/v4l1compat.so skype

Once skype is launched test the camera and see if the camera capture is now uninverted, through menus:

S -> Options -> Video Devices -> Test

Skype Options Video devices screenshot

2. Create a skype Wrapper script Launcher

To make skype launch everytime with exported shell variable:
LD_PRELOAD=/usr/lib32/libv4l/v4l1compat.so

A new skype wrapper bash shell script should be created in /usr/local/bin/skype , the file should contain:

#!/bin/sh
LD_PRELOAD=/usr/lib32/libv4l/v4l1compat.so
/usr/bin/skype

To create the script with echo in a root terminal issue;

root@linux:~# echo '#!/bin/sh' >> /usr/local/bin/skype
root@linux:~# echo 'LD_PRELOAD=/usr/lib32/libv4l/v4l1compat.so' >> /usr/local/bin/skype
root@linux:~# echo '/usr/bin/skype' >> /usr/local/bin/skype
root@linux:~# chmod +x /usr/local/bin/skype

3. Edit the Skype gnome menu to substitute /usr/bin/skype Skype Launcher with /usr/local/bin/skype

Gnome 2 has a handy menu launcher, allowing to edit and add new menus and submenus (menus and items) to the Application menu, to launch the editor one has to click over Applications with last mouse button (right button) and choose Edit Menus

GNOME Edit menus screenshot

The menu editor like the one in the below screenshot will appear:

GNOME 2 Menu Editor Screenshot

In the preceeding Launcher properties window, Command: skype has to be substituted with:

GNOME2 Skype screenshot Launcher properties

Command: /usr/local/bin/skype

For console freaks who doesn't want to bother in editting Skype Launcher via GUI /usr/share/applications/skype.desktop file can be editted in terminal. Inside skype.desktop substitute:

Exec=skype

with

Exec=/usr/local/bin/skype

Skype fixed inverted bat like screenshot

As one can imagine the upside-down video image in Skype is not a problem because of Linux, but rather another bug in Skype (non-free) software program.
By the way everyone, who is using his computer with Free Software operating system FreeBSD, Linux etc. knows pretty well by experience, that Skype is a very problematic software; It is often a cause for system unexpected increased system loads, problems with (microphone not capturing), camera issues, issues with pulseaudio, problem with audio playbacks … Besides the long list of bugs there are unexpected display bugs in skype tray icon, bugs in skype messanger windows and at some rare occasions the program completely hangs and had to be killed with kill command and re-launched again.

Another worrying fact is Skype's versions available for GNU / Linux and BSD is completely out of date with its "competitor" operating systems MS Windows, MacOS X etc.
For people like me and my friend who want to use free operating system the latest available skype version is not even stable … current version fod download from skype's website is (Skype 2.2Beta)!

On FreeBSD the skype situation is even worser, freebsd have only option to run Skype ver 1.3 or v. 2.0 at best, as far as I know skype 2.2 and 2.2beta is not there.

Just as matter of comparison the latest Skype version on Windows is 5.x. Windows release is ages ahead its Linux and BSD ver. From a functional point of view the difference between Linux's 2.x and Windows 5.x is not that much different, what makes difference is is the amount of bugs which Linux and BSD skype versions contain…
Skype was about 6 months ago bought by Microsoft, therefore the prognosis for Skype Linux support in future is probably even darker. Microsoft will not probably bother to release new version of Skype for their competitor free as in freedom OSes.

I would like to thank my friend and brother in Christ Stelian for supplying me with the Skype screenshots, as well as for being kind to share how he fixed his camera with me.