I am using ubuntu 10.10. In my rails 3.1 project, i am not able to upload any type of image files. While uploading an image file it shows an validation error like

/tmp/image1.jpg is not recognized by the 'identify' command.

My ruby version is,
ruby 1.9.3p327

I have installed both ImageMagick & rmagick gem & some other libdev tools. Now my rmagick gem is
rmagick (2.13.1)
&...