Resize a picture or PDF file by 50% of its original form and save it as a PDF:
$ convert rose.jpg -resize 50% rose.pdf
Well, ‘convert’ may be used to convert between most of the known image formats —- not just JPG and PDF!
N.B. 1. More options may be found at the ImageMagick website. More information on how to specify the geometry may be found here. (If you don’t have ImgeMagick you need to install it first — see the first link for more information on installation!).
2. Here is a list of other useful options/ examples on how to make the best out of ‘convert’.
3. If you’re at playing with PDFs you may also be interested in joining and removing pages from a PDF document using Ghostscript — see a previous post here.