Merging Multiple VOB Files Into a Single VOB File Using Command Line Tool in Linux

Often DVDs come with two notable directories: AUDIO_TS and VIDEO_TS. Usually VIDEO_TS is used for watching the video files contained in that DVD. These videos are formatted in VOB files, in almost all cases. Sometimes it’s better to convert these VOB files into a more usual video format, like mp4, avi, etc. You have to merge the VOB files into a single VOB file in the first step. And you can combine the VOB files into one using the Unix tool cat. cat is a simple and yet powerful tool for catenation of multiple files into one.

Open terminal in the VIDEO_TS directory (of course you can open terminal in another directory and still specify the input files path in the command; Unix is that flexible!) and execute the following command in it:

cat *.VOB > ./give_any_name.VOB

This would combine all VOB files into a single VOB file in that directory. Of course, you can specify another directory for output file, and give any name to the output file.

Here, * (asterisk) character acts as a wild card denoting all the files ending with VOB. And ./ denotes the present working directory.

Missing Libraries While Compiling DWM in Debian 8 Jessie

While compiling dwm – dynamic window manager in Debian 8 “jessie”, I got the following error:

dwm.c:33:28: fatal error: X11/cursorfont.h: No such file or directory
compilation terminated.
make: *** [dwm.o] Error 1


dwm.c:40:37: fatal error: X11/extensions/Xinerama.h: No such file or directory
compilation terminated.
make: *** [dwm.o] Error 1

The catch here is libx11-dev and libxinerama-dev packages are needed to compile dwm and that’s the workaround for the error messages. Therefore installing these packages using the following command fixed the issue:

apt-get install libx11-dev libxinerama-dev

Instaling Fonts in Debian Without Any GUI Tool

One-click-fonts-install GUI utility for installing fonts like gnome-font-viewer are available in Debian. But installing fonts without using any GUI tool is much for straightforward and fun. You just need to copy the fonts in a specific directory in which Debian would search for fonts to use. That’s all.

Debian searches for fonts in some specified directories. The directories are specified in /etc/fonts/fonts.conf file. You can open this file in your system to see which directories holds the fonts. Usually, /usr/share/fonts, /usr/X11R6/lib/X11/fonts, /usr/local/share/fonts, etc. directories hold fonts which are available system wide. Better yet, use ~/.fonts directory that would make the fonts available only for your account or userid. Understandably this .fonts directory resides in your home directory, the path being ~/.fonts, or /home/your_userid/.fonts. Therefore, copy the fonts you would use in this directory to make them available for your user account or userid.

Say, a directory named font_collections holds your desired fonts. Open terminal from this directory and execute the following command to copy all the fonts from this directory to .fonts directory in your home folder:

cp * ~/.fonts

The * (asterisk) character used here acts as an wild card; meaning it denotes every file in the specified directory. Assuming your font_collections directory holds only fonts, the above command would copy all of them inĀ  ~/.fonts.

If your font_collections directory holds fonts and other files, then you can mention every fonts file by their extension and copy only them with the following command:

cp *.ttf ~/.fonts

Assuming your fonts are in ttf (True Type Font) format.

You can also copy the fonts without being in the directory that holds the font. Just use the following command format:

cp /path/to/the/directory/that/holds/fonts/* ~/.fonts

That would do the job of copying fonts. Now, you have to re-generate fonts cache file to make your system aware of the updated ~/.fonts directory. Open terminal and execute the following command:

fc-cache -fv

This would make the fonts available for you. Open any text/word processing application, and see the fonts appear in that application, and use them, of course!

Setting Wallpaper Using Feh in Openbox

feh is a fast, yet powerful command line image viewer. It’s a swiss-army-knife for images, and fits perfectly for setting wallpaper in openbox window manager. You can choose it to set wallpaper in openbox, instead of those GUI-based tools and get the job done with ease.

To set a wallpaper using feh, open the terminal emulator and execute the command in the following format:

feh --bg-scale /path/to/the/image/file

Wallpaper can be set in any scaling options: tile, center, fill, max or scale. Replace scale in the above command with any scaling option you like.

Mention the path of the image file replacing /path/to/the/image/file in the above command.

Once you’ve set wallpaper using feh, it creates a .fehbg file in your home directory. The path is understandably ~/.fehbg.

To have the wallpaper there that you’ve set using feh every time you login, or when you begin a new session, add the following line in your ~/.config/openbox/autostart script:

sh ~/.fehbg &

This would make your wallpaper appear evey time you start a new session.