install vmtools

For a regular desktop intsall :

sudo apt-get install open-vm-tools

For a server install:

sudo apt-get install --no-install-recommends open-vm-tools

image resize

http://tech-artists.org/forum/showthread.php?t=1673

# Python code:
import maya.OpenMaya as om

def resizeImage(sourceImage, outputImage, width, height):

    image = om.MImage()
    image.readFromFile(sourceImage)

    image.resize( width, height )
    image.writeToFile( outputImage, 'png')


resizeImage('<sourceImage.png>','<outputImage.png>', 800, 600)