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Record audio and video from webcam using mencoder

Record audio to MP3 stream and video to MPEG-4 stream from webcam to AVI file using mencoder. Gives floating point exception in some mencoder versions.
This is sample output - yours may be different.
6

mencoder tv:// -tv driver=v4l2:width=800:height=600:device=/dev/video0:fps=30:outfmt=yuy2:forceaudio:alsa:adevice=hw.2,0 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=1800 -ffourcc xvid -oac mp3lame -lameopts cbr=128 -o output.avi

ivalladt · 2009-09-15 19:46:06 5
View webcam output using mplayer

View webcam output using mplayer, with correct fps and outfmt settings according to my webcam model.
This is sample output - yours may be different.
5

mplayer tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video0:fps=30:outfmt=yuy2

ivalladt · 2009-09-15 19:41:41 5
Execute all SQL files in a directory
This is sample output - yours may be different.
0

cat *.sql | mysql <db_name>

rehanift · 2009-09-15 17:28:35 3
Record audio and video from webcam using ffmpeg

Record from a webcam, audio using ALSA encoded as MP3, video as MPEG-4.
This is sample output - yours may be different.
5

ffmpeg -f alsa -r 16000 -i hw:2,0 -f video4linux2 -s 800x600 -i /dev/video0 -r 30 -f avi -vcodec mpeg4 -vtag xvid -sameq -acodec libmp3lame -ab 96k output.avi

ivalladt · 2009-09-15 17:03:25 5
convert a,b,c to ('a','b','c') for use in SQL in-clauses
This is sample output - yours may be different.
1

echo a,b,c | sed -e s/,/\',\'/g -e s/^/$\'/ -e s/$/\'$/

sharfah · 2009-09-15 15:52:01 5
Remove all files but one starting with a letter(s)

Remove everything in current directory except files starting with "ca".
This is sample output - yours may be different.
1

rm -rf [a-bd-zA-Z0-9]* c[b-zA-Z0-9]*

arcege · 2009-09-15 14:22:56 7
Extract audio track from a video file using mencoder

Extracts an MP3 encoded audio stream from an input video file.
This is sample output - yours may be different.
3

mencoder -of rawaudio -ovc copy -oac mp3lame -o output.mp3 input.avi

ivalladt · 2009-09-15 11:28:01 3
Substitute audio track of video file using mencoder

Creates a new video file with video stream copied from input file and a different audio stream
This is sample output - yours may be different.
2

mencoder -ovc copy -audiofile input.mp3 -oac copy input.avi -o output.avi

ivalladt · 2009-09-15 11:26:05 3
Remove sound from video file using mencoder

Remove sound from input video file, output video stream is copied from input video stream, with no audio.
This is sample output - yours may be different.
1

mencoder -ovc copy -nosound input.avi -o output.avi

ivalladt · 2009-09-15 11:22:51 6
Fix UTF-8 text files misinterpreted as ISO 8859-1 due to Byte Order Mark (BOM) of the Unicode Standard.

Fixes the faulty files with perl, which may exist on more platforms
This is sample output - yours may be different.
0

perl -i -pe 's/\xef\xbb\xbf//g' <file>

pfredrik · 2009-09-15 11:22:43 4

This command creates tar zip of a directory and its sub-directories. Show Sample Output

tar cvfz dir_name.tgz dir/

unixmonkey6220 · 2009-09-15 10:20:20 4

Happy Days

AFAIR this is the wording ;)
This is sample output - yours may be different.
5

echo {'1,2,3',4}" o'clock" ROCK

danam · 2009-09-15 10:12:49 11
Incase you miss the famous 'C:\>' prompt
This is sample output - yours may be different.
1

export PS1='C:${PWD//\//\\\}>'

jldbasa · 2009-09-15 10:06:25 4
Find UTF-8 text files misinterpreted as ISO 8859-1 due to Byte Order Mark (BOM) of the Unicode Standard.

Same thing, only "head" instead of grep/egrep.. Show Sample Output
This is sample output - yours may be different.
```
Match: ./wps.ear/wps.war/themes/html/QPG/pageHeader.html
```
0

find -type f |while read a;do [ "`head -c3 -- "${a}"`" == $'\xef\xbb\xbf' ] && echo "Match: ${a}";done

pfredrik · 2009-09-15 08:43:21 3
Backup files older than 1 day on /home/dir, gzip them, moving old file to a dated file.

Useful for backing up old files, custom logs, etc. via a cronjob. Show Sample Output
This is sample output - yours may be different.
```
-rw-rw-r--    1 root     root        46705 Sep 13 14:30 file2.rpm
-rw-rw-r--    1 rms      rms         46705 Sep 13 14:30 file22.rpm

-rw-rw-r--    1 root     root        44227 Sep 13 14:30 file2.rpm_2009-09-15.gz
-rw-rw-r--    1 rms      rms         44228 Sep 13 14:30 file22.rpm_2009-09-15.gz
```
9

find /home/dir -mtime +1 -print -exec gzip -9 {} \; -exec mv {}.gz {}_`date +%F`.gz \;

sagan · 2009-09-15 06:49:59 10
Setting reserved blocks percentage to 1%

According to tune2fs manual, reserved blocks are designed to keep your system from failing when you run out of space. Its reserves space for privileged processes such as daemons (like syslogd, for ex.) and other root level processes; also the reserved space can prevent the filesystem from fragmenting as it fills up. By default this is 5% regardless of the size of the partition. http://www.ducea.com/2008/03/04/ext3-reserved-blocks-percentage/
This is sample output - yours may be different.
2

sudo tune2fs -m 1 /dev/sda4

bassel · 2009-09-14 21:11:55 5
Testing hard disk reading speed
This is sample output - yours may be different.
13

hdparm -t /dev/sda

bassel · 2009-09-14 21:04:08 9
Check variable has been set

Works in all shells. Does not require a test. Handles like an assertion. Show Sample Output
This is sample output - yours may be different.
```
sh: VAR: unset variable
```
-1

: ${VAR:?unset variable}

arcege · 2009-09-14 19:41:01 4
erase content from a cdrw
This is sample output - yours may be different.
1

cdrecord -v -blank=all -force

eastwind · 2009-09-14 19:21:15 7
burn an iso to cd or dvd
This is sample output - yours may be different.
-1

cdrecord -v path_to_iso_image.iso

eastwind · 2009-09-14 19:20:12 4
random xkcd comic

i sorta stole this from http://www.shell-fu.org/lister.php?id=878#MTC_form but it didn't work, so here it is, fixed. --- updated to work with jpegs, and to use a fancy positive look behind assertion.
This is sample output - yours may be different.
6

display "$(wget -q http://dynamic.xkcd.com/comic/random/ -O - | grep -Po '(?<=")http://imgs.xkcd.com/comics/[^"]+(png|jpg)')"

grokskookum · 2009-09-14 18:40:14 5
Check variable has been set
This is sample output - yours may be different.
1

[ -z "$VAR" ] && echo "VAR has not been set" && exit 1

sharfah · 2009-09-14 17:03:16 4
Happy Days

This never gets old Show Sample Output
This is sample output - yours may be different.
```
you'll just have to see now wont you
```
4

echo {1..3}" o'clock" ROCK

JackiesJungle · 2009-09-14 15:39:07 5
view file content with echo

another replacement for cat.
This is sample output - yours may be different.
-2

echo "$(</etc/issue)"

mobidyc · 2009-09-14 09:44:35 34
search for a file in PATH

Also searches for aliases and shell builtins Show Sample Output
This is sample output - yours may be different.
```
root@fs3:~# type nvgui
nvgui is /usr/bin/nvgui
root@serv:~# type rm
rm is /bin/rm
root@fs3:~# type alias
alias is a shell builtin
root@serv:~# 
```
4

type <filename>

danam · 2009-09-14 09:37:23 5
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Show all mergeinfo for a svn subtree

Human readable directory sizes for current directory, sorted descending

a function to find the fastest DNS server

http://public-dns.info 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.

Pull up remote desktop for other than gnome/kde eg fluxbox

If the remote doesn't export its desktop (eg fluxbox, blackbox etc) then you need to run a x11vnc server there and a vncviewer at the local end. This command does the lot for you - it assumes that you can 'ssh' to the box without a password and that x11vnc is installed at the remote end.

delete unversioned files in a checkout from svn

A "Web 2.0" domain name generator and look for register availability

You would need pwgen installed first, on ubuntu you can get it by apt-get $ sudo apt-get install pwgen

Short Information about loaded kernel modules

I modify 4077 and marssi commandline to simplify it and skip an error when parsing the first line of lsmod (4077). Also, it's more concise and small now. I skip using xargs ( not required here ). This is only for GNU sed. For thoses without GNU sed, use that : $ modinfo $(lsmod | awk 'NR>1 {print $1}') | sed -e '/^dep/s/$/\n/g' -e '/^file/b' -e '/^desc/b' -e '/^dep/b' -e d

Block an IP address from connecting to a server

This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

Show directories in the PATH, one per line

quoteless

Get yesterday's date or a previous time

With this command you can get a previous or future date or time. Where can you use this? How about finding all files modified or created in the last 5 mins? touch -t `echo $(date -d "5 minute ago" "+%G%m%d%H%M.%S")` me && find . -type f -newer me List all directories created since last week? touch -t `echo $(date -d "1 week ago" "+%G%m%d%H%M.%S")` me && find . -type d -cnewer me I'm sure you can think of more ways to use it. Requires coreutils package.

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