A super fast and simple retina (@2x, @3x) image converter.
You can download the prebuilt application from the releases, or just download / fork the project and build it yourself.
After you've got the app running, you can drag single files, multiple files and directories to convert @3x or @2x images. Dragging is allowed in the Retini window as well as the App Icon in the Dock.
The resized images will be placed in the same directory as the source file. The resizing goes like this:
| Generated? | Drag @3x file | Drag @2x file |
|---|---|---|
| @2x | √ | × |
| 1x | √ | √ |
The original file will never be altered, the @2x and 1x are copies. If you drag a @3x file, the 1x file generated will be generated from the (original) @3x, so no double conversion loss.
You can drag a file with a @1x extension, Retini will scale this to a @2x and @3x file. This is nice for pixel art, upscaling is done via the nearest neighboor filter / algorithm.