How do I convert a mp3 plus one image to flv?

[crirus]

Hello

I am trying to convert an mp3 plus cover image to flv, but I can't seems to make it work automatically,

I have this so far
/usr/bin/ffmpeg -loop_input -t 80 -f image2 -i store/large/1.jpg -i /store/1.mp3 -y -f flv -acodec libmp3lame -ab 64 -ac 1 /store/1.flv

-t is for how long to repeat, but then flv ends on 80 seconds, mp3 length is not accounted.
Any way to automate this to input parameters?

Thanks
Cris