Applies a Gaussian blur to the image. You can specify the strength of the blur. Higher values make the image blurrier.

For example, if you have the following image with no blur:
You can use the Blur transformation to change it to:

If you add the IMQuery transformation to a policy, use the im variable, and select Blur, you can use a query string to blur any image using this policy. See Syntax and Examples for the syntax for the query string parameter.