Commands by mrehqe (5)

  • Convert all wma to [email protected] with ffmpeg into directory.

    for f in *.wma; do ffmpeg -i "$f" -ab 128k "${f%.wma}.mp3" -ab 128K; done
    mrehqe · 2011-11-25 17:48:26 4
  • Crop several images by imagemagik's convert command. substitute , ,, with pixel value and with a different existent directory.

    for k in *.png; do convert $k -crop <width>x<high>+<cropwidth>+<cropthigh> <newpath>/$k; done
    mrehqe · 2011-11-14 17:04:15 4

  • 0
    sed ':a;N;$!ba;s/\n\n/\n%\n/g' input.txt >output
    mrehqe · 2011-11-06 11:55:33 0
  • Use w_scan to build italian DTT video channel list. To change country, substitute IT with 2 letter country code. Userful to be played in vlc by: vlc -f dvb-channels.conf Show Sample Output

    w_scan -X -P -t 2 -E 0 -c IT > dvb-channels.conf
    mrehqe · 2011-11-04 11:17:31 0
  • Great for telnet stream. Substitute aa with caca for colour. To see in terminal: cat video.txt Show Sample Output

    mplayer -vo aa:eight:driver=curses video.avi >video.txt
    mrehqe · 2011-10-31 10:06:10 0

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Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

show the difference

Show all detected mountable Drives/Partitions/BlockDevices
Yields entries in the form of "/dev/hda1" etc. Use this if you are on a new system and don't know how the storage hardware (ide, sata, scsi, usb - with ever changing descriptors) is connected and which partitions are available. Far better than using "fdisk -l" on guessed device descriptors.

Convert the contents of a directory listing into a colon-separated environment variable
Useful for making a CLASSPATH out of a list of JAR files, for example. Also: export CLASSPATH=.:$(find ./lib -name '*.jar' -printf '%p:')

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"

a function to find the fastest DNS server gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

Extract the emoticons regex from a running skype process
Skype has an internal regex which depicts the emoticons it supports. However you cannot simply search the binary file for it. This small 181 character line will do just that, provided skype is running. And of course, only works in linux.

Remove all the files except abc in the directory
Finds all files in the current directory and deletes them besides file called "abc"

Combine all .mpeg files in current directory into one big one.
Good old cat & output redirection. Using this method you can combine all kinds of things - even mpeg files. My video camera makes a series of .mpeg files that are broken into 4gb chunks. Using this command I can easily join them together. Even better, combined with the cp command the files can be copied and joined in one step.

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