This is Digital photo editing tool.
EditBy: The first alpha version of RawTherapee 3.0 is available for download. Note that this is not a feature complete version. In V3.0 both major
GUI/workflow and Algorithm changes are planned. This alpha version demonstrates the new, much more efficient GUI, but it does not contain
any algorithmic changes yet.

The most significant changes in the GUI are the following:

multi-tab interface
the real Batch processing support arrived: select multiple images and adjust them together (the multi-adjust behavior of some parameters is selectable in the preferences dialog: they can be either additive or absolute)
completely re-written editor: preview and detail view are now gone. The main image view can be magnified as required, and only the necessary part of the image will be re-calculated. There is a small navigator, too, and infinitely many detailed views can be opened to INVESTigate fine Details.
16 bit thumbnails (an option, takes double disk space)
before/after view in the editor you can free download Raw Therapee for Linux 3.0 Alpha 1 now.