Download of Dfine2 2.0 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available.
Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. The actual developer of this software for Mac is Nik Software. The software lies within Design & Photo Tools, more precisely Viewers & Editors.
From the developer:
Dfine gives you unprecedented control over exactly how much and where to apply noise reduction. This makes it ultra-easy to eliminate noise in your images while maintaining detail and sharpness, thus improving the quality of every digital photo you take. Dfine 2.0 is designed to prevent the loss of detail other noise reduction tools often introduce.
You may want to check out more software for Mac, such as Sweet Home 3D, EazyDraw or ImageJ, which might be similar to Dfine2.