Posts Tagged ‘xvidcap’

Best software available today for Linux video Desktop capturing on Debian

Tuesday, April 19th, 2011

Reading Time: 4minutes
I’ve been experimenting since some time in order to understand better what is the current situation with Video Desktop Capturing Software available today for Linux and FreeBSD.

My previous investigations has led me to write an article about xvidcap calledHow to make Video from your Linux Desktop with xvidcap

Though xvidcap works pretty well, it is currently uncapable of capturing the audio stream of a Linux Desktop env and hence part of the interactivity of the videos is missing when used.

A bit of further investigation on the topic has pointed me to 3 free software programs which are capable to record Desktop environment on Linux with sound embedded

The interesting screen video capturing Desktop tools I’ve found are:

1. recordMyDesktop
2. Istanbul
and
3. vnc2swf

Installing them on a Debian based distribution is pleasable, as there are installable debian packages of each one which I installed easily with apt:

debian:~# apt-get install istanbul recordmydesktop gtk-recordmydesktop vnc2swf

RecordMyDesktop‘s package contains a command line little tool which when started directly starts capturing video and audio of the Linux Desktop. After a Ctrl+C is pressed the program quits, saves and encodes the video in ogg-encapsulated theora-vorbis file format.

Here is the output I got in saving a sample file by launching recordmydesktop without any arguments:

hipo@debian:~/Desktop$ recordmydesktop
Initial recording window is set to:
X:0 Y:0 Width:1024 Height:768
Adjusted recording window is set to:
X:0 Y:0 Width:1024 Height:768
Your window manager appears to be Metacity

Initializing…
Buffer size adjusted to 4096 from 4096 frames.
Opened PCM device hw:0,0
Recording on device hw:0,0 is set to:
2 channels at 22050Hz
Capturing!
Broken pipe: Overrun occurred.
Broken pipe: Overrun occurred.
Broken pipe: Overrun occurred.
^C
*********************************************

Cached 5 MB, from 207 MB that were received.
Average cache compression ratio: 97.3 %

*********************************************
Saved 69 frames in a total of 69 requests
Shutting down..Broken pipe: Overrun occurred.

STATE:ENCODING
Encoding started!
This may take several minutes.
Pressing Ctrl-C will cancel the procedure (resuming will not be possible, but
any portion of the video, which is already encoded won’t be deleted).
Please wait…
Output file: out.ogv
[100%]
Encoding finished!
Wait a moment please…

Done.
Written 692529 bytes
(635547 of which were video data and 56982 audio data)

Cleanning up cache…
Done!!!
Goodbye!

The captured file as I you see in the above output is saved in file out.ogv

RecordMyDesktop has also a GUI interface (written in Python) called gtk-recordmydesktop

Below you see a screenshot of the GUI gtk-recordmydesktop:

RecordMyDesktop GTK interface entry screen

gtk-recordmydesktop is a super-easy to use as you already see in the picture, you can either configure it with Advanced button or use Save As button to select where you want the Desktop captured video and audio to be stored.

In Debian Squeeze 6.0, the Advanced GUI button interface button is not working but that’s not such an issue, as the rest of the buttons works fine.
After the recordmydesktop‘s Record button is pressed it will start capturing from your Desktop and the window seen in the above screenshot will disappear/hide in the system tray:

recordmydesktop recording minimized in system tray
When you press over the white little square in the system tray the screen capturing will be interrupted and a window will pop-up informing you that the captured video and audio is being encoded, here is another screenshot of recordmydesktop encoding a saved Desktop video stream:

recordmydesktop saving captured desktop video

After the final .ogv file is encoded and saved to further transfer it into (.flv) I used ffmpeg;

debian:~# ffmpeg -i test.ogv test.flv
...

Now let’s evaluate a bit on the the final results, the produced test.ogv‘s synchronization between sound and video was not good as the sound was starting earlier than the video and therefore even though recordmydesktop used to be highly praised on the net, the proggie developers still needs to do some bug fixing
Further on, I continued and (gave the other Desktop screen capturer) Istanbul a try hoping that at least with it the video and audio of my Linux desktop will be properly captured. But guess what, the results with Istanbul was even more unsatisfactory as the produced videos and sounds, were slow and a lot of frames from the screens were missing completely.
Moreover the sound which was supposed to accompany the video was completely 🙁

Thus I will skip on talking about Istanbul as in my view, this piece of software is far away from being production ready.

I also tested vnc2swf , launched it by: pressing alt+f2 and typing in vnc2swf in GNOME’s run application prompt, just to be surprised by an error …:

vnc2swf error no 111 Connection refused

The reason for this error is caused by the xserver (Xorg) port 5900 is being closed by default on Debian

However this error is easily solvable, by making the Xserver to listen to a the port 5900, to make the Xorg server on Debian to listen on this port you need to edit the file:

/etc/X11/xinit/xserverrc

and change inside it:

exec /usr/bin/X -nolisten tcp "$@"

with:

exec /usr/bin/X "$@"

and either reboot your Linux or restart only the Xorg server by pressing Ctrl+Alt+BackSpace

Now let me conclude, the results from my desktop video screen capturing experiments prooved that vnc2swf is superior (as it is capable of properly saving a movie with sound and video from a Linux Desktop). It appears this soft is actually the best one you can use to make a video of your Linux desktop.

Sadly my testing has proven that Linux is still lacking behind Windows and Mac in even doing the most simple tasks …
Let’s hope that situation will get better soon and Gnome or KDE developers will soon provide us with better software capable to save properly a video and audio captured from the Linux Desktop.

How to make Video from your Linux Desktop with xvidcap / Capture desktop output in a video on Linux

Wednesday, April 6th, 2011

Reading Time: 2minutes
If you have wondered on how to create videos aiming at manuals on how you do certain stuff on Linux, let’s say related to programming or system administration.
Then you should definitely check out

xvidcap

Below is the package description as taken from apt-cache show xvidcap

A screen capture enabling you to capture videos off your X-Window desktop
for illustration or documentation purposes. It is intended to be a
standards-based alternative to tools like Lotus ScreenCam.

On Debian based Linux systems (e.g. Debian Ubuntu) xvidcap is available straight from the package repositories. To install and test it you can straight issue:

linux:~# apt-get install xvidcap
...

To start using xvidcap, either by starting it with alt+f2 in gnome or straight launch it from the applications menu via:

Applications -> Sound & Video -> xvidcap

Here is how the xvidcap program looks like right after you start it;
xvidcap screenshot main menu

As you see in the screenshot xvidcap’s menu interface is extraordinary simple.

As you see it only has a stop, pause, rec, back and forward buttons, a capture selector and movie editor.
Pitily xvidcap does not support music capturing, but at least for me that’s not such an issue.

If you click over the field test-0000.mpeg[0000] with your last mouse button, you will notice a drop down menu with an option for preferences of xvidcap.

Take the time to play with the preferences, since there are quite a few of them.

The most important preference that you might like to straightly adjust in my view is in the:

Preferences -> Multi-Frame tab -> File Name:

The default file that xvidcap uses to store it’s content files as you will see in the preferences is utest-%04d.mpeg

If you want to change the type of the output file format to let’s say flv change the File Name: value to utest-%04d.flv
Next time you record with xvidcap, you will have the file stored in flv format.

The red lines which you see in the above screenshot is the capture area, you will have to also tune the screen capture area before you can proceed with recording a video from your desktop.

The way to capture your Desktop in fullscreen is a bit unusual, you first need to mark up all your visible Desktop and before that you will have to select from xvidcap’s preferences from:

Preferences -> General -> Minimize to System Tray

By selecting this option each time you press the xvidcap’s record button the xvidcap’s controller interface will be minimized to tray and capturing the video of the region previously selected with the capture selector will start up.