Imagecache.module provides the most commonly-used processes needed for basic image manipulation.
This package provides a suite of additional processes that can be added to the imagecache pipeline, including:

• Watermarking - a much requested addition that enables you to place any image anywhere over a source picture, with alpha transparency
• Overlays - Add photo-corners etc to the image
• Text overlay - add a short copyright notice to your image, using available system fonts
• Color-shifting - Colorize images. Also invert.
• Brighten/Darken
• Alpha blending - turn an image into a transparent mask, and back into a flat image against another color
• Canvas manipulation - add padding, either onto color or transparent backgrounds
• Background - Place your image onto another source background
• File Format switcher - If you need tranparency in JPGs : make them PNG. If your PNG thumbnails are 30K each, save them as JPGs
• Rounded corners (transparent). With input from canaryMason, we can even set different radius for different corners, and round just one corner etc.
• Aspect Switcher new 2009-08 - lets you perform different actions or use different dimensions based on whether the image is 'landscape' or 'portrait'
• Custom Actions - Execute your own PHP/GD code in the middle of an imagecache generation process. Requires some familiarity with imageAPI internals.

These functions, combined with the available scale,crop,rotate functions already provided by imagecache make hundreds of image processing effects available.

The DRUPAL-6 release requires Imagecache.
It integrates slightly with image.module, imagefield.module, filefield.module, upload.module if available - to supply node data that can be used in the text overlay action.

Many imagecache actions just do not work with the ImageMagick Toolkit. To use imagecache_actions, you will either have to just use the built-in GD toolkit or help contribute imageMagick - compatible scripts that do the job. Those scripts have not yet been written by people that actually use ImageMagick. - help wanted

Original effort on the canvas/layers was contributed to imagecache1 by Dimm. This was reworked into doprys rewritten API by dman, and many extra bits (especially better transparency support) was added.
"Independant" rounded corners were enabled with code contributed by CanaryMason

This project is open for contributors to add more effects, as the imagecache API allows any modules to add their own effects to the library. It exists as a project separate from ImageCache proper purely for management purposes.

Related See also : smartcrop - to zoom on the most "interesting" section of an image; Scale9 - to slice and position graphic corner and border effects like picture frames onto images. More may be listed on the imagecache project page

ImageMagick support is very limited (I don't use or test it) and relies on user contributions to move forward.

Click the below example images to view the settings details
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