with browsers which don't support this feature natively.

for 300 dpi, change number to "3" to "6" if you want to check for 600dpi).

Crop marks finally work directly in Javascript, even with lots of pages.
Wonder why it does not work on Balsa project though.

layering the different images for each channel and page.

to jpg, for each color channel, for each page.
In progress: generation of a webpage to have an interface to check those
channels.

USAGE
    ./colorSepatation.sh input.pdf

USAGE:
    ./rgb2cmyk.sh input.pdf

OUTPUT:
    input-cmyk.pdf

You can specify the height of them in the variables at the top of
`print.less`. If `height = 0`, then it's like they don't exist.
You can also specify their content in the variables for easier use.
As an example, the header has a mirrored running title and the footer
has a pagination.