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Delete files older than x days

Posted by Kelvin on 22 Mar 2011 | Tagged as: Ubuntu

This entry is part 10 of 19 in the Bash-whacking series

Delete files older than 7 days:

cd /path/to/dir
find -mtime +7 -exec rm {} \;

Change +7 to +14 for deleting files older than 14 days.

Reset wireless in Ubuntu 10.04 Lucid

Posted by Kelvin on 04 Mar 2011 | Tagged as: Ubuntu

This entry is part 9 of 19 in the Bash-whacking series

Ever had your Intel wireless card play up on you in Ubuntu? You can't seem to reset it like the ethernet cards (i.e. with ifup and ifdown). Do this instead:

sudo rmmod iwlagn && sudo modprobe iwlagn

Replace iwlagn with your wireless card module name if you don't have an intel wireless card.

gnome and gedit shortcut awesomeness

Posted by Kelvin on 28 Feb 2011 | Tagged as: Ubuntu

Anyone on Ubuntu will probably have used gedit at one time or the other.

Well, gedit just got cooler.

Turns out you can map/remap shortcuts on all gnome-based applications including gedit by changing a simple setting.

1. Hit Alt-F2, enter gconf-editor
2. Go to desktop > gnome > interface
3. check can_change_accels

Now in gconf-editor, click the Edit menu, you should see a menu entry called "List Recent Keys". Move your mouse over the entry, then press any keyboard combination, say Ctrl-L. You should now see Ctrl-L on the right of "List Recent Keys".

Ha! You've now mapped Ctrl-L to the "List Recent Keys" menu item.

And you can do this for all apps which are gnome-compliant, including gedit of course…

Download google video and youtube from command-line

Posted by Kelvin on 22 Feb 2011 | Tagged as: Ubuntu

This entry is part 8 of 19 in the Bash-whacking series

clive is an awesome tool for downloading google video and youtube flash videos from the command-line.

sudo apt-get install clive
 
# download google video in flv
clive http://video.google.com/videoplay?docid=-1388254997387483895
 
# download youtube in mp4
clive --format=mp4 http://www.youtube.com/watch?v=JPyuH4qXLZ0
 
# download list of URLs in file
cat urls.txt | clive

Flatten folder/directory tree

Posted by Kelvin on 16 Jan 2011 | Tagged as: Ubuntu

For example, to move all mp3 files in sub directories into the current dir:

find . -name *.mp3 -exec mv {} . \;

Recursively copy only files with certain extension with rsync

Posted by Kelvin on 16 Jan 2011 | Tagged as: Ubuntu

This entry is part 6 of 19 in the Bash-whacking series

Sometimes you want to get to all MP3 or PDF files which are nested in a deep directory tree. Here's what you do..

rsync -rvtW --delay-updates --modify-window=1 --progress --include='*.pdf' --include='*.xml' --exclude='*.*' source dest

Useful ffmpeg commands

Posted by Kelvin on 06 Dec 2010 | Tagged as: Ubuntu

This entry is part 5 of 19 in the Bash-whacking series

Shameless ripped from http://www.catswhocode.com/blog/19-ffmpeg-commands-for-all-needs

Getting infos from a video file

ffmpeg -i video.avi

Turn X images to a video sequence

ffmpeg -f image2 -i image%d.jpg video.mpg
This command will transform all the images from the current directory (named image1.jpg, image2.jpg, etc…) to a video file named video.mpg.

Turn a video to X images

ffmpeg -i video.mpg image%d.jpg
This command will generate the files named image1.jpg, image2.jpg, …

The following image formats are also availables : PGM, PPM, PAM, PGMYUV, JPEG, GIF, PNG, TIFF, SGI.

Encode a video sequence for the iPpod/iPhone

ffmpeg -i source_video.avi input -acodec aac -ab 128kb -vcodec mpeg4 -b 1200kb -mbd 2 -flags +4mv+trell -aic 2 -cmp 2 -subcmp 2 -s 320×180 -title X final_video.mp4
Explanations :

Source : source_video.avi
Audio codec : aac
Audio bitrate : 128kb/s
Video codec : mpeg4
Video bitrate : 1200kb/s
Video size : 320px par 180px
Generated video : final_video.mp4

Encode video for the PSP

ffmpeg -i source_video.avi -b 300 -s 320×240 -vcodec xvid -ab 32 -ar 24000 -acodec aac final_video.mp4
Explanations :

Source : source_video.avi
Audio codec : aac
Audio bitrate : 32kb/s
Video codec : xvid
Video bitrate : 1200kb/s
Video size : 320px par 180px
Generated video : final_video.mp4

Extracting sound from a video, and save it as Mp3

ffmpeg -i source_video.avi -vn -ar 44100 -ac 2 -ab 192 -f mp3 sound.mp3
Explanations :

Source video : source_video.avi
Audio bitrate : 192kb/s
output format : mp3
Generated sound : sound.mp3

Convert a wav file to Mp3

ffmpeg -i son_origine.avi -vn -ar 44100 -ac 2 -ab 192 -f mp3 son_final.mp3

Convert .avi video to .mpg

ffmpeg -i video_origine.avi video_finale.mpg

Convert .mpg to .avi

ffmpeg -i video_origine.mpg video_finale.avi

Convert .avi to animated gif(uncompressed)

ffmpeg -i video_origine.avi gif_anime.gif

Mix a video with a sound file

ffmpeg -i son.wav -i video_origine.avi video_finale.mpg

Convert .avi to .flv

ffmpeg -i video_origine.avi -ab 56 -ar 44100 -b 200 -r 15 -s 320×240 -f flv video_finale.flv

Convert .avi to dv

ffmpeg -i video_origine.avi -s pal -r pal -aspect 4:3 -ar 48000 -ac 2 video_finale.dv
Or:
ffmpeg -i video_origine.avi -target pal-dv video_finale.dv

Convert .avi to mpeg for dvd players

ffmpeg -i source_video.avi -target pal-dvd -ps 2000000000 -aspect 16:9 finale_video.mpeg
Explanations :

target pal-dvd : Output format
ps 2000000000 maximum size for the output file, in bits (here, 2 Gb)
aspect 16:9 : Widescreen

Compress .avi to divx

ffmpeg -i video_origine.avi -s 320×240 -vcodec msmpeg4v2 video_finale.avi

Compress Ogg Theora to Mpeg dvd

ffmpeg -i film_sortie_cinelerra.ogm -s 720×576 -vcodec mpeg2video -acodec mp3 film_terminée.mpg

Compress .avi to SVCD mpeg2

NTSC format:

ffmpeg -i video_origine.avi -target ntsc-svcd video_finale.mpg
PAL format:

ffmpeg -i video_origine.avi -target pal-svcd video_finale.mpg

Compress .avi to VCD mpeg2

NTSC format:
ffmpeg -i video_origine.avi -target ntsc-vcd video_finale.mpg

PAL format:
ffmpeg -i video_origine.avi -target pal-vcd video_finale.mpg

Multi-pass encoding with ffmpeg

ffmpeg -i fichierentree -pass 2 -passlogfile ffmpeg2pass fichiersortie-2

Download youtube videos as mp3

Posted by Kelvin on 04 Dec 2010 | Tagged as: Ubuntu

This entry is part 4 of 19 in the Bash-whacking series

For Ubuntu..

sudo apt-get install ffmpeg
 
cd ~/bin
wget https://github.com/rg3/youtube-dl/raw/2010.11.19/youtube-dl
chmod +x youtube-dl
 
wget http://www.supermind.org/scripts/youtube2mp3
chmod +x youtube2mp3

The contents of youtube2mp3 is simple:

#!/bin/bash
#!/bin/bash
 
x=/tmp/.youtube-dl-$RANDOM-$RANDOM.flv
youtube-dl --output=$x --format=18 "$1"
ffmpeg -i $x -vn -ar 44100 -ac 2 -ab 256k -f mp3 "$2"

Now get the youtube URL you want to convert to MP3, and run it like so:

youtube2mp3 <youtube_url>

For example:

youtube2mp3 http://www.youtube.com/watch?v=cFhaBEtmHeU

Move up multiple directories in bash

Posted by Kelvin on 04 Dec 2010 | Tagged as: Ubuntu

This entry is part 3 of 19 in the Bash-whacking series

Ever thought typing cd.. 5 times was silly? Try this up() function!

Add this to .bash_profile or .bashrc

up () {
    if [ -z $1 ]; then
        cd ..
    elif [ $1 -gt 0 ]; then
        let count=0
        while [ $count -lt $1 ]; do
            cd ..
            let count=count+1
        done
    else
        echo "Argument must be a positive integer."
    fi
    pwd
}

The script in action:

kelvin:~/java/search/apache-solr-1.4.0/src/java/org/apache/solr/search$ up 5
kelvin:~/java/search/apache-solr-1.4.0/src$

Recursively delete .svn folders

Posted by Kelvin on 04 Dec 2010 | Tagged as: Ubuntu

This entry is part 2 of 19 in the Bash-whacking series
#!/bin/bash
find ./ -name ".svn" | xargs rm -Rf

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