# [texhax] pdfLaTeX graphicx viewport

Adrian F. Clark alien at essex.ac.uk
Thu Feb 24 10:56:20 CET 2005

```I'm sorry if I seem dim but I have googled for the answer to this and
looked in both my normal LaTeX reference books before asking.

I want to include part of a JPEG image in a pdfLaTeX document.  Rather
than cropping the region out the image, I thought I'd use the viewport
option to graphicx's \includegraphics:

\includegraphics[viewport=0 0 1536 2048,clip]{2005-01
-12-045}

But what are meaning of the 4 values one specifies in the context of a
JPEG image?  (The question is also made more interesting by the fact
that I need to rotate the image through 90 degrees, but I'll
investigate that more thoroughly after I'm able to crop it properly.)

MTIA.