[vox-tech] Changing the print resolution of JPEG images by script

[David Hummel]

On Fri, Apr 08, 2005 at 03:12:38PM -0700, Henry House wrote:
> 
> One of the more common operations that I need to do with JPEG images
> is to change their print resolution so that when printed (e.g., as
> included figures in a LaTeX document) they print at 300 dpi (for
> example) instead of 72 dpi. I have been doing this in the Gimp. This
> causes the JPEGs to be recompressed with loss of quality when the Gimp
> saves the files.
> 
> - Is there any ways to change the print resolution, short of editing
> the JPEGs by hand, without recompressing them?
> 
> - Is there any utility in existance that could do this from the
> command line? I tried the jpegtran program from libjpeg-progs in
> Debian, but it does not seem to have this capability.

The "convert" program in the imagemagick package might do what you want.

-David