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script to perform a task on each file in a directory

Hello,
I need a script that runs:
mplayer kickboxing01.wmv -frames 1 -vo jpeg quality=90:outdir=./ -ao null
rm 00000001.jpg
convert 00000002.jpg -resize 50% -crop 140x120+20 th_kickboxing01.jpg

on each file in a directory.

So, instead of 'kickboxing01.wmv' it would be all <name>.wmv files in a given directory.
and each converted jpg would have its respective th_<name>.jpg

Currently, I run the script in the directory of the wmv files, due to complications in mplayer writing out the jpg.

Thanks,

Gordie

Kim Ryan

You could do this with a perl script

@wmv_files = <*.wmv>;
foreach $file (@wmv_files)
{
$base_name = ($file =~ /(.*)\.wmv/);
system("mplayer kickboxing01.wmv -frames 1 -vo jpeg quality=90:outdir=./ -ao null");
system("rm 00000001.jpg");
system("convert 00000002.jpg -resize 50% -crop 140x120+20 th_$base_name\.jpg");
}
You may need to add the full path to your mplayer and convert programs

ahoffmann

find . -type f -name \*.wmv -exec echo "mplayer {} -frames 1 -vo jpeg quality=90:outdir=./ -ao null; rm 00000001.jpg; convert 00000002.jpg -resize 50% -crop 140x120+20 th_{}" \; |sh

# for testing simply omit the final |sh

kailee

ASKER

ahoffmann,
your solution gets:
convert: unable to open image `th_./061007.wmv': No such file or directory.

teraplane,
your solution gets:
./thumb2: line 1: syntax error near unexpected token `;'
./thumb2: line 1: `@wmv_files = <*.wmv>;'

ahoffmann

> .. `th_./061007.wmv': No such file or directory.
damn, missed that find returns paths

> on each file in a directory.
ls *.wmv| awk '{print "mplayer "$1" -frames 1 -vo jpeg quality=90:outdir=./ -ao null; rm 00000001.jpg; convert 00000002.jpg -resize 50% -crop 140x120+20 th_"$1}' |sh

kailee

ASKER

ahoffmann,
now the thumbs are named '.wmv'
they're jpgs.

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ahoffmann

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kailee

ASKER

sorry for the delay, I get 'undetermined string'.

OZO, gimme a hand!!!!!

kailee

ASKER

I ran
ls *.mpg|sed -e 's/$.*$$\..*$/\1 \2/'
and get the file listing with a space before '.mpg'

kailee

ASKER

oh, I got it, missing close-quotes at the end.

ahoffmann

does my suggestion work?

kailee

ASKER

Yes.
Thanks.
If I put
mplayer "$1$2" -frames 1 -vo jpeg quality=90:outdir=./ -ao null; rm 00000001.jpg; convert 00000002.jpg -resize 50% -crop 140x120+20 th_"$1".jpg

in a file, like make_jp.pl, would the vars be passed into this file as it ran? That would make this very flexible.

ahoffmann

> .. would the vars be passed into this file as it ran?
yes, assuming your script is named "myscript", then start it like

myscript par1 par2

kailee

ASKER

I mean something like,
ls *.wmv|sed -e 's/$.*$$\..*$/\1 \2/'| awk '{print "gen_process.script"}' |sh

Oh, I think you mean that myscript would contain
ls $par1|sed -e 's/$.*$$\..*$/\1 \2/'| awk '{print "par2$"}' |sh

where par2 would be gen_process.script

am I correct?

ahoffmann

> am I correct?
sound like you a bit confused, or am I with your intend

1. parameters in shell script are referenced by $1, $2 and so on ...
2. you can assign the parameters to variables in shell, like
par1="$1"
and then use it like:
echo "first parameter was $par1"
3. $1, $2, etc have different meaning in awk
4. $1 etc. in awk are not related to the calling shell anyhow
5. passing shell variables to awk is difficult, you either need a proper quoting or pass the variables as values of the input stream, or use gawk with -v option