Many tools are available these days for image editing. In addition to common applications, such as GIMP, several tools exist for specific image processing scenarios. One of them is Photivo [1], which is based on the Lab function (see the "Lab Color Model" box). Because Photivo can read RAW files, its use normally precedes image processing (e.g., what you'd do with GIMP).

Photivo has many RGB functions and is suitable for processing 16-bit RAW files and bases all its capabilities on them. The program also supports formats like TIFF, PNG, and JPEG. If you've never worked with the Lab color model, then you should familiarize yourself with GIMP to start with.

First Steps

Photivo can be found in the repository of many Linux distributions, but with Ubuntu, you will have to add a specific ppa:

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