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Convert multiple files using avidemux
Using avidemux to convert multiple files that are in the folder where the command was executed.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Append stdout and stderr to a file, and print stderr to the screen [bash]
Useful for cron jobs -- all output will be logged but only errors will cause email to be sent. NB the order of "2>&1" and ">> logfile" is important, it doesn't work if you reverse them (everything goes to the logfile, nothing left for tee).

Url Encode
Converts reserved characters in a URI to their percent encoded counterparts. Alternate python version: $ echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())'

create screencast (record text and audio simultaneously) using 'script' and 'arecord'
This shell function takes a single argument, which is used as the base name of the .wav, .timing and .session files created. To create a screencast: $ screencast test type and talk ... then type 'exit' or to exit the screencast. test.wav will contain the audio from your screencast. test.session will contain text and control characters needed to paint the screen test.timing will contain timing information needed to synch individual keystrokes in test.session with the audio. to play back: $ aplay test.wav & scriptreplay test.{timing,session} NOTE: because the shell function uses the variable "$!", and bash likes to expand '!' during history expansion, you will need to turn off bash's history before you enter the shell function. This can be achieved using the command $set +H

Shows size of dirs and files, hidden or not, sorted.
Enhanced version: fixes sorting by human readable numbers, and filters out non MB or GB entries that have a G or an M in their name.

Get all the keyboard shortcuts in screen
Displays a list of all the basic keyboard shortcuts in screen.

Create a transition between two videos
We take the first 50 frames of a.mp4 for track a, and 24 blank frames followed by b.mp4 for track b. We then create a transition from track a to track b starting from frame 25 and ending at frame 49. The output is stored in out.mp4 To view the results without saving remove "-consumer avformat:out.mp4" from the end. Documentation of the mlt framework and the melt command can be found here: http://www.mltframework.org/bin/view/MLT/Documentation

Compress blank lines

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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