This program will take an image file and create randomly oriented postcard-sized images from it.
  It also creates printable page-sized images and a composite image of all postcards pasted together.
  It requires ImageMagick, downloadable from http://www.imagemagick.org.
  It also requires Math::Trig, downloadable from http://search.cpan.org/~jhi/Math-Complex-1.56/lib/Math/Trig.pm.

Basic usage:
make_postcards.pl <input file>
  creates 20 postcard images, 638x825 (approx quarter-page sized for 8.5"x11" at 150 dpi) and puts them in the 'postcards' directory.

Full usage:
perl make_postcards.pl <input file>
  --help                     print this help
  --verbose                  run verbosely, with extra informative output
  --width <width>            create postcards <width> pixels wide (default=638)
  --height <height>          create postcards <height> pixels high (default=825)
  --border <border width>    create postcards with a <border width>-pixel white border (default=19)
  --num_images <num_images>  create num_images postcards (default=20)
  --output <output folder>   put output in the <output_folder> directory (default='postcards')
  --method <method>          use <method> to determine postcard locations (default='uniform'); options are 'uniform' and 'circle'
  --preview                  in addition to creating postcard and page images, create preview images showing the area for each postcard to be created

Examples:
perl make_postcards.pl --border 0 original.jpg
  creates 20 postcard images from original.jpg, with no border, and puts them in the 'postcards' directory.
perl make_postcards.pl --verbose --num_images 8 --preview original.jpg
  creates 8 postcard images from original.jpg, with preview images, and puts them in the 'postcards' directory.
perl make_postcards.pl --method circle --verbose --num_images 40 noisebridge.png
  creates 40 postcard images from noisebridge.png, using the 'circle' method, and puts them in the 'postcards' directory.