[reportlab-users] any way to create pdf files with different dpi resolutions?

Robin Becker reportlab-users@reportlab.com
Sun, 3 Aug 2003 01:11:31 +0100

In article <20030802232508.99678.qmail@web21206.mail.yahoo.com>, Ryan
Grow <ryangrow@yahoo.com> writes
>Is it possible to use reportlab to create PDF
>documents with higher resolution than 72 dpi? I notice
>there is a setting in units.py for inch = 72.0 - but I
>do not see a way to modify this value through the API.
..... PDF uses points ie 1/72 inch as its standard unit, but the
resolution is much higher than that. Internally adobe uses fixed point
values with 16.16 binary bits. So you can expect to resolve values which
are 1/72 * 1/2**16 inches apart. That should be enough for most
purposes. In practice the resolution will be determined by the printing

The use of fixed point does have consequences though. You can't expect
to transform by factors of a million and then reverse the transformation
to get the start value again.
Robin Becker