Commands by brettalton (5)

  • Convert PNG to GIF

    (relies on 'imagemagick') Convert all .png files to .gif. This can also go the other way if you reverse the file extensions in the command, e.g.: for file in *.gif; do convert "$file" "$(basename $file .gif).png"; done If the file is named 'example1.png' it will be named 'example1.gif' when it is complete.


    4
    for file in *.png; do convert "$file" "$(basename $file .png).gif"; done
    brettalton · 2009-02-15 23:39:08 5
  • Convert PDF to JPG

    (relies on 'imagemagick') This command will convert all .pdf files in a directory into a 800px (wide or height, whichever is smaller) image (with the aspect ratio kept) .jpg. If the file is named 'example1.pdf' it will be named 'example1.jpg' when it is complete. This is a VERY worthwhile command! People pay hundreds of dollars for this in the Windows world. My .jpg files average between 150kB to 300kB, but your's may differ. Show Sample Output


    30
    for file in `ls *.pdf`; do convert -verbose -colorspace RGB -resize 800 -interlace none -density 300 -quality 80 $file `echo $file | sed 's/\.pdf$/\.jpg/'`; done
    brettalton · 2009-02-15 23:27:43 4
  • Extract .daa files with PowerISO

    .daa is a non-standard disk image format that can not be read by any other program. This is how you can extract the files though. PowerISO binary for Linux: http://www.poweriso.com/poweriso-1.3.tar.gz "This is a free utility for linux which can extract, list, and convert image files (including ISO, BIN, DAA, and other formats). Type " poweriso -? " for detailed usage information. File Size: 278KB"


    -2
    ./poweriso extract $USER/file.daa / -od $USER/file_extracted
    brettalton · 2009-02-15 23:19:40 0
  • View your motherboard's ACPI tables (in Debian & Ubuntu)

    In July 2008, there was an uproar over Foxconn motherboards feeding Linux installs incorrect ACPI information (http://ubuntu-virginia.ubuntuforums.org/showthread.php?t=869249). Foxconn has gladly corrected their mistake, but make sure it's not happening on your motherboard! After running the command, just view the 'dsdt.dsl' in any editor you like. Show Sample Output


    -1
    sudo aptitude -y install iasl && sudo cat /sys/firmware/acpi/tables/DSDT > dsdt.dat && iasl -d dsdt.dat
    brettalton · 2009-02-15 23:13:50 0
  • Concatenate (join) video files

    Use mencoder to concatenate (join) multiple video files together. Show Sample Output


    9
    mencoder -forceidx -ovc copy -oac copy -o output.avi video1.avi video2.avi
    brettalton · 2009-02-15 23:05:32 1

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Install pip with Proxy
Installs pip packages defining a proxy

Remove annoying files from recently extracted zip archive
Inspired by http://www.commandlinefu.com/commands/view/2573/remove-all-files-previously-extracted-from-a-tar.gz-file. .... yet for zip files

shell function to underline a given string.
underline() will print $1, followed by a series of '=' characters the width of $1. An optional second argument can be used to replace '=' with a given character. This function is useful for breaking lots of data emitted in a for loop into sections which are easier to parse visually. Let's say that 'xxxx' is a very common pattern occurring in a group of CSV files. You could run $ grep xxxx *.csv This would print the name of each csv file before each matching line, but the output would be hard to parse visually. $ for i in *.csv; do printf "\n"; underline $i; grep "xxxx" $i; done Will break the output into sections separated by the name of the file, underlined.

Update zone file Serial numbers
Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. $rndc reload should usually follow this command.

Run a long job and notify me when it's finished
You will need libnotify-bin for this to work: $ sudo aptitude install libnotify-bin

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Open Remote Desktop (RDP) from command line having a custom screen size
This example uses xfreerdp, which builds upon the development of rdesktop. This example usage will also send you the remote machine's sound.

Merge video files together using mencoder (part of mplayer)
Using mplayer's mencoder, you can merge video files together. '-oac' specifies the audio encoding (here copy, to just copy and not compress) '-ovc' specifies the video encoding (same thing).

List upgrade-able packages on Ubuntu
Taken from apticron and modified.

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" }

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