plplot12-driver-gd 5.10.0-0ubuntu4 (i386 binary) in ubuntu trusty

 PLplot is relatively small, portable, freely distributable, and is rich
 enough to satisfy most users. It has a wide range of plot types including
 line (linear, log), contour, 3D, fill, and almost 1000 characters
 (including Greek and mathematical) in its extended font set. The package
 is designed to make it easy to quickly get graphical output; only a
 handful of function calls is typically required. For more advanced use,
 virtually all aspects of plotting are configurable.
 .
 This package provides the GD driver module for PLplot. It allows the
 generation of PNG and JPEG files directly from PLplot programs. The GD
 driver is no longer actively maintained upstream and is likely to be
 dropped in a future release. The cairo and qt drivers offer newer, and
 better alternatives.