• Apache 2.2.x
• Imagemagick 6.6+
• libcurl 7.18.0+

Add the following to the Apache configuration:

<IfModule !mod_dims.c>
    LoadModule dims_module modules/mod_dims.so
</IfModule>

AddHandler dims-local .gif .jpg

<Location /dims/>
    SetHandler dims
</Location>

<Location /dims3/>
    SetHandler dims3
</Location>

<Location /dims-status/>
    SetHandler dims-status
</Location>

This assumes mod_dims.so has been installed in $HTTP_ROOT/modules.

There are three classes of errors in mod_dims;

• Errors caused during downloading of a source image. These come directly from libcurl and are logged as-is.

• Errors caused during an ImageMagick operation. These come directly from ImageMagik and are logged as-is.

• Errors caused during processing of a request by mod_dims. These fall into the category of bad input checking, bad config, etc.

[client Imagemagick operation, '', timed out after 4 ms

would be something like "Resize/Image" or "Save/Image".

Errors will be in the following format in Apache's error log:

[client ] error, '', on request:

For example:

[client 10.181.182.244] Imagemagick error, 'no decode delegate for this image format `'', on request: /20080803WI55426251_WI.jpg/TEST/thumbnail/78x100/

These message are usually self explanatory so no explain is provided. The URL that failed will be logged along with this message.

• Couldn't connect to server
• Couldn't resolve DNS
• Timeout was reached

• Requested URL has hostname that is not in the whitelist. (aaolcdn.com)
• Application ID is not valid
• Parsing thumbnail geometry failed
• Parsing crop geometry failed
• Failed to read image This occurs if ImageMagick had trouble reading the image.
• Unable to stat image file This occurs when a local request is unable to find the image to resize.

• Memory allocation failed This should rarely occur, if ever, but usually when it does it's the result of an ImageMagick timeout.

• unrecognized image format

• no decode delegate for this image format

This happens when ImageMagick doesn't no how to read a source image.

• zero-length blob not permitted

This may occur if there was a failure to download the source image.

• Unsupported marker type 0x03 This may occur if the image is corrupted. The "0x03" may be different depending on the corruption.

Any errors that have "Assertion failed" are results of bugs in the code and can be considered serious.

• Assertion failed: (wand->signature == WandSignature), function MagickGetImageFormat, file wand/magick-image.c, line 4137.