What is "cinepaint"

CinePaint is an open source computer program for painting and retouching bitmap frames of films. It is a fork of version 1.0.4 of the GNU Image Manipulation Program (GIMP). It enjoyed some success as one of the earliest open source tools developed for feature motion picture visual effects and animation work. The main reason for this adoption over mainline gimp was its support for high bit depths (greater than 8-bits per channel) which can be required for film work. The mainline GIMP project later added high bit depths in GIMP 2.9.2, released November 2015. It is free software under the GNU General Public License.