[magick-users] Re: Filters in PNG

[John J Foerch]

Claus Cyrny <claus.cyrny at web.de> writes:
> Hi Fred,
>
> many thanks. Especially the article the second link points to is really
> great. What I was actually referring to, though, are the PNG-specific
> filter options to reduce the file size (none, sub, up, average, paeth).
> Can I specify those as well somewhere? Those option are mentioned
> in the entry on '-quality'.
>
> Claus
>

Hello Claus,

The filter type is specified numerically as the second digit of the
arg to -quality.

http://imagemagick.org/script/command-line-options.php#quality

John Foerch