And after that, it will come about, says the Lord, that I will send my spirit on all flesh; and your sons and your daughters will be prophets, your old men will have dreams, your young men will see visions:
Joel 2:28 (BBE)
GIMP is the GNU Image Manipulation Program; a powerful application for raster image authoring, retouching and composition. GIMP is a scriptable, expandable, extendable image application with a nice GUI.
GIMP can open, display, convert and save to all sorts of image file formats, including BMP, GIF, JPG, PCX, PDF, PNG, PS, PSD, SVG, TIF and more. GIMP features painting tools (Airbrush, Brush, Clone, Pencil) including gradients, blending, custom brushes and patterns, anti-aliasing, and much, much more.
GIMP has support for animation, multiple undo and redo, layers (incl. editable text layers) and channels (incl. alpha channel support), transformable paths, a foreground extraction tool, transformations (incl. flip, rotate, scale and shear) and extractions. GIMP is plug-in friendly; there are well over 100 plug-ins available.
More info: GIMP.org, User Manual, FAQ, Tutorials. See Complete Intro to GIMP 2017/2018 [videos], FLOSS Manual, GIMPology, GIMP tips and tricks, Getting Started with Gimp 2.8 ~ Tutorials for Beginners [videos], Logos By Nick [videos] GIMP Tutorials, GIMP Addons @ pling, and How to GIMP Tutorials.
GIMP is free and open source software licensed under the GPL.
LibreOffice-Draw offers import and export support for BMP, GIF, JPEG, PNG, TIFF, and WMF. It will also save projects as an SWF (Flash) file. Draw offers two and three-dimensional rotation; group, ungroup, regroup (and editing while graphics are still grouped); can use textures, lighting effects and transparency; can change perspectives, be used to make network diagrams and flowcharts; and features page sizes big enough to make posters. See Draw Basics by libreofficehelp.com, Draw Topics from LPG Computer Fundamentals and Video Tutorials from FrugalComputerGuy. Also check out the LibreOffice-Draw official Homepage.
LibreOffice-Draw is free, open source software licensed under the LGPL.
Pinta is a simple, cross-platform, bitmap drawing and raster image-editing application. It features floating windowed toolbars and / or docked toolbars, primary and secondary palette color swapping, layer support and unlimited undo. See Pinta’s homepage. See the Pinta User Guide. See one minute tutorials, videos and articles on the Web under Pinta Documentation. Also see Pinta on Learn Ubuntu MATE.
Pinta is free and open source software licensed under the MIT license.
Screenshot is GNOME Screenshot; a GUI tool that can capture the whole desktop, a single window, with or without the cursor, and with or without a time delay. Found under Accessories (as simply Screenshot) in the Menu, it’s a “prettier” way to take screen shots. See A comprehensive guide to taking screenshots in Linux using gnome-screenshot on HowToForge, the GNOME Screenshot Ubuntu Manpage and The Geek Stuff article Methods to Take Screenshot Capture in Ubuntu Linux.
GNOME Screenshot is free and open source software licensed under the GPL.