Commands tagged transcoding (1)

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Get a BOFH excuse
Gets a BOFH excuse from the BOFH excuse server (towel.blinkenlights.nl port 666), and passes it through sed and tr to get rid of telnet connection stuff.

Convert AVI to iPhone MP4
Fir3net.com

Renaming a file without overwiting an existing file name
Sometimes in a hurry you may move or copy a file using an already existent file name. If you aliased the cp and mv command with the -i option you are prompted for a confirmation before overwriting but if your aliases aren't there you will loose the target file! The -b option will force the mv command to check if the destination file already exists and if it is already there a backup copy with an ending ~ is created.

Efficiently extract lines between markers
GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made. In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start'). My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.

Clean up the garbage an accidental unzipping makes
List out all the names from the zip file and pass it to xargs utility to delete each one of them

grep tab chars
mixing tabs and spaces for indentation in python would confuse the python interpreter, to avoid that, check if the file has any tab based indentation. "^V" => denotes press control + v and press tab within quotes. $ cat improper_indent.py class Tux(object): print "Hello world.." $ grep " " improper_indent.py print "Hello world.."

list block devices
Shows all block devices in a tree with descruptions of what they are.

Record a webcam output into a video file.
The option -an disables audio recording, -f forces the use of video4linux for the input, -s sets the video to the size 320x240, -b sets the recording bitrate, -r sets the frame rate to 15fps, -i gives the input device, -vcodec sets the output format. Press Q to stop recording or you can specify the recording time with the -t option like -t 00:1:30

display a one-liner of current nagios exit statuses. great with netcat/irccat

Downsample mp3s to 128K
This will lower the quality of mp3 files, but is necessary to play them on some mobile devices.


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