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String manipulation in bash

I'm trying to make a bash script for nautilus that converts a flv-file to mpg. I can't rename the new file properly. The file name.flv should be called name.mpg when converted. Pretty simple. The basic idea is this:

Code:

#!/bin/bash



#triple backspace to delete flv-ending in filename

b="^H^H^H"



ffmpeg -i "$1" "$1""$b"mpg

"$1": is input filename
"$1""$b"mpg: is output filename

I've tried many different versions of this, but the best of them only converts to a filename where the backspace characters are reckognized as some weird symbol. How do I manipulate the string properly?

Code:

b=${1/flv/mpeg}

man bash
substitution

edit:
ah not the good variable, this is one correct answer:

ffmpeg -i "$1" ${1/flv/mpeg}

Hi,

Something like this should work: ${1%%.flv}.mpg

ffmpeg -i "$1" ${1%%.flv}.mpg (i did not check to see if the quotes are needed).

This uses bash' parameter expansion (see manpage for more details).

Hope this helps.

Thanks. Both suggestions work.

There is also

for x in *flv; do ffmpeg -i "$x" "${x/.flv/.mpg}";done

If you have a big job to do and want to take lunch early.