Drupal: GD Image Filtering Low Quality / Poor > Performance

I'm getting this message in my Drupal installation:

GD Image Filtering Low Quality / Poor Performance

The installed version of PHP GD does not support image filtering(desaturate, blur, negat开发者_运维技巧e, etc). It was probably compiled using the official GD libraries from http://www.libgd.org instead of the GD library bundled with PHP. You should recompile PHP --with-gd using the bundled GD library. See http://www.php.net/manual/en/image.setup.php. An implementation of imagefilter in PHP will be used in the interim.

I'm using the default GD library in php on Ubuntu 9.04

What are the exact commands to update this library ?

You could install php from dotdeb. The issue is that debian compiles gd without the extensions that php has added to gd.

The other option is to install ImageMagick and tell drupal to use imagemagick instead of gd. For me image magick works much better than gd anyway. I tried to limit users to uploading 1200x1200 max size images and was always running out of memory in php when they upload larger images.

apt-get install imagemagick

dotdeb is the simplest solution. If you're running LAMP off of Debian/Ubuntu, you do want dotdeb in your sources in general and not just for this specific issue.