1. Download ImageMagick http://www.imagemagick.org/script/command-line-tools.php
2. Install it.
3. The convert.exe can be used as command. (C:\Program Files (x86)\ImageMagick-6.8.2-Q16\convert.exe)
4. Syntax: convert.exe <input image file full path> -resize <width>x<height> <output image file full path>
For example: convert.exe d:\input.jpg -resize 200x100 d:\input_resized_200x100.jpg
