The application takes, as command line input, an image file,
the image file is then converted to greyscale and each pixel
is given a transparency value according to its greyscale
value.
The application is recommended for use with scanned images,
with a uniform white background, however a photo taken in
good light may also produce good results.
It will take as input the image formats:
PNG, GIF, JPG, TIFF, and BMP
The application will write the output PNG file into the same
directory as the input file with the suffix _alpha.png