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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands tagged convert from sorted by
Terminal - Commands tagged convert - 70 results
utime(){ python -c "import time; print(time.strftime('%a %b %d %H:%M:%S %Y', time.localtime($1)))"; }
utime(){ awk -v d=$1 'BEGIN{print strftime("%a %b %d %H:%M:%S %Y", d)}'; }
utime(){ date -d "1970-01-01 GMT $1 seconds"; }
utime { date -d @$1; }
2010-05-12 12:21:15
User: deltaray
Functions: date

More recent versions of the date command finally have the ability to decode the unix epoch time into a human readable date. This function makes it simple to utilize this feature quickly.

ffmpeg -i input.avi -s qcif -vcodec h263 -r 20 -b 180k -acodec libfaac -ab 64k -ac 2 -ar 22050 output.3gp
2010-04-24 23:01:21
User: mariusbutuc


-i = input file name

-s = set frame size, qcif=176x144

-vcodec = force video codec

-r = frame-rate [default = 25]

-b = bit-rate [200 kb/s]

-acodec = force audio codec

-ab = audio bitrate in bits/s [64k]

-ac = no. of audio channels [1]

-ar = audio sampling frequency [44100 Hz]


-sameq = use same video quality as source (implies VBR)

-f = force format

-y = overwrite output files

echo $ascii | perl -ne 'printf "%x", ord for split //'
echo $ascii | perl -ne 'printf ("%x", ord($1)) while(/(.)/g); print "\n";'
echo $hex | perl -pe 's/(..)/chr(hex($1))/ge'
pv -cN orig < foo.tar.bz2 | bzcat | pv -cN bzcat | gzip -9 | pv -cN gzip > foo.tar.gz
2010-04-16 05:21:10
User: rkulla
Functions: gzip

In this example we convert a .tar.bz2 file to a .tar.gz file.

If you don't have Pipe Viewer, you'll have to download it via apt-get install pv, etc.

for file in *.flac; do flac -cd "$file" | lame -q 0 --vbr-new -V 0 - "${file%.flac}.mp3"; done
convert in.pdf out.jpg
utime(){ perl -e "print localtime($1).\"\n\"";}
2009-11-06 12:58:10
User: MoHaG
Functions: perl

A shell function using perl to easily convert Unix-time to text.

Put in in your ~/.bashrc or equivalent.

Tested on Linux / Solaris Bourne, bash and zsh. using perl 5.6 and higher.

(Does not require GNU date like some other commands)

ffmpeg -i input.mov -b 4096k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi
2009-10-21 05:44:31
User: oracular

Convert those .mov files that your digital camera makes to .avi

Adjust the bitrate (-b) to get the appropriate file size. A larger bitrate produces a larger (higher quality) .avi file and smaller bitrate produces a smaller (lower quality) .avi file.

Requires ffmpeg (see man page for details)

(tested with canon camera MOV files)

Other examples:

ffmpeg -i input.mov -sameq -vcodec msmpeg4v2 -acodec pcm_u8 output.avi ffmpeg -i input.mov -b 1024k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi
chr () { echo -en "\0$(printf %x $1)"}
chr() { printf \\$(printf %o $1); }
chr () { printf \\$(($1/64*100+$1%64/8*10+$1%8)); }
2009-10-15 07:01:54
User: dennisw
Functions: printf

I've corrected the function. My octal conversion formula was completely wrong. Thanks to pgas at http://mywiki.wooledge.org/BashFAQ/071 for setting me straight. The new function is from pgas and is very fast.

ffmpeg -i inputfile.mp4 outputfile.flv
2009-09-10 14:49:14
Tags: ffmpeg convert

This converts any media ffmpeg handles to flash. It would actually convert anything to anything, it's based on the file extension. It doesn't do ANY quality control, sizing, etc, it just does what it thinks is best. I needed an flv for testing, and this spits one out easily.

dos2unix file.txt
2009-08-19 11:59:22
User: slim

Whereas ^V is CTRL-V.

converts a dos file to unix by removing 0x13 characters

for a in `ls`; do echo $a && convert $a -resize <Width>x<Height> $a; done
2009-08-02 22:35:24
User: leavittx
Functions: echo

Resizes all images in the curent directory to x resolution.

It is better than `mogrify -resize *.jpg` because of independence from extension of image (e.g. .jpg and .JPG) (: