Commands by nickleus (9)

  • convert all flac files in a folder to mp3 files with a bitrate of 192 kbps


    5
    for f in *;do flac -cd $f |lame -b 192 - $f.mp3;done
    nickleus · 2010-10-19 07:55:11 0
  • split large video file

    i have a large video file, 500+ MB, so i cant upload it to flickr, so to reduce the size i split it into 2 files. the command shows the splitting for the first file, from 0-4 minutes. ss is start time and t is duration (how long you want the output file to be). credit goes to philc: http://ubuntuforums.org/showthread.php?t=480343 NOTE: when i made the second half of the video, i got a *lot* of lines like this: frame= 0 fps= 0 q=0.0 size= 0kB time=10000000000.00 bitrate= 0.0kbit just be patient, it is working =) Show Sample Output


    2
    ffmpeg -i 100_0029.MOV -ss 00:00:00 -t 00:04:00 100_0029_1.MOV
    nickleus · 2010-08-08 23:43:28 0
  • convert flac to mp3

    if you haven't already done so, install lame and flac: sudo apt-get install lame flac Show Sample Output


    2
    flac -cd input.flac |lame -h - output.mp3
    nickleus · 2010-03-05 23:54:21 1
  • set your ssd disk as a non-rotating medium

    if you still get a permissions error using sudo, then nano the file: sudo nano -w /sys/block/sdb/queue/rotational and change 1 to 0 this thread: http://www.ocztechnologyforum.com/forum/showpost.php?p=369836&postcount=15 says that this will "help the block layer to optimize a few decisions"


    5
    sudo echo 0 > /sys/block/sdb/queue/rotational
    nickleus · 2009-11-27 12:16:17 3
  • find read write traffic on disk since startup

    The iostat command is used for monitoring system input/output device loading by observing the time the devices are active in relation to their average transfer rates. in ubuntu to get the iostat program do this: sudo apt-get install sysstat i found this command here: http://www.ocztechnologyforum.com/forum/showthread.php?t=54379 Show Sample Output


    3
    iostat -m -d /dev/sda1
    nickleus · 2009-11-27 12:00:48 0
  • convert mp3 to ogg

    why would you want to convert mp3's to ogg? 1 reason is because ardour doesn't support mp3 files because of legal issues. this is really the only reason you would do this, unless you have really bad hearing and also want smaller file sizes, because converting from one lossy format to another isn't a good idea. Show Sample Output


    -1
    mp32ogg file.mp3
    nickleus · 2009-11-16 20:22:48 0
  • convert wav files to ogg

    cd to the folder containing the wav files and convert them all to ogg format. in my sample output i use the -a and -l flags to set the author and album title. to get the oggenc program in ubuntu linux run: sudo apt-get install oggenc Show Sample Output


    2
    oggenc *.wav
    nickleus · 2009-11-11 14:26:01 1
  • convert wav files to flac

    cd to the folder containing the wav files, then convert them all to flac. yeah baby! in ubuntu, to get the flac program just: sudo apt-get install flac flac file input formats are wav, aiff, raw, flac, oga and ogg Show Sample Output


    3
    flac --best *.wav
    nickleus · 2009-11-11 14:17:24 2
  • search ubuntu packages to find which package contains the executable program programname

    search ubuntu's remote package source repositories for a specific program to see which package contains it Show Sample Output


    7
    apt-file find bin/programname
    nickleus · 2009-11-10 10:21:45 2

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Enter a command but keep it out of the history
Put a space in front of your command on the command line and it will not be logged as part of your command line history.

Create a listing of all possible permissions and their octal representation.

track flights from the command line
Usage: flight_status airline_code flight_number (optional)_offset_of_departure_date_from_today So for instance, to track a flight which departed yesterday, the optional 3rd parameter should have a value of -1. eg. flight_status ua 3655 -1 output --------- Status: Arrived Departure: San Francisco, CA (SFO) Scheduled: 6:30 AM, Jan 3 Takeoff: 7:18 AM, Jan 3 Term-Gate: Term 1 - 32A Arrival: Newark, NJ (EWR) Scheduled: 2:55 PM, Jan 3 At Gate: 3:42 PM, Jan 3 Term-Gate: Term C - C131 Note: html2text needs to be installed for this command. only tested on ubuntu 9.10

small CPU benchmark with PI, bc and time.
$ # 4 cores with 2500 pi digits $ CPUBENCH 4 2500 $. $ every core will use 100% cpu and you can see how fast they calculate it. $ if you do 50000 digitits and more it can take hours or days

Install pip with Proxy
Installs pip packages defining a proxy

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"

Recursive Line Count

Easy way to scroll up und down to change to one of n last visited directories.
This alias is meant to append n (here is n=10) most recently used cd commands to the bottom of history file. This way you can easily change to one of previous visited directories simply by hitting 1-10 times arrow up key. Hint: You can make more aliases implying the same rule for any set of frequently used long and complex commands like: mkisof, rdesktop, gpg...

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" }

create random numbers within range for conjob usage
if you need to install cron jobs in a given time range.

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