Difference between revisions of "GIMP"

Revision as of 15:00, 10 March 2019

GIMP is a full featured graphic / image / photo editing software set of programs and tools similar in use or functionality to Adobe Photoshop. GIMP (GNU Image Manipulation Program) is extensive enough that its own wiki page can be devoted to the software tools.

Gimp / GIMP (technically all upper case) will provide for you nearly all of the features and tools available in the expensive commercial software package Adobe Photoshop with the exception that GIMP is absolutely free. Also, unlike Adobe Photoshop, GIMP is cross-platform and open source. You can run GIMP under Linux, Windows, and MacOS. Many Linux distributions include GIMP as a part of their desktop operating systems, including Fedora and Debian.

Tools used to perform image editing can be accessed via the toolbox, through menus and dialogue windows. They include filters and brushes, as well as transformation, selection, layer and masking tools.

GIMP uses an interface made up of multiple independent windows, which can be confusing for some users. You can toggle between the default multi-window mode and the new single-window mode in GIMP 2.8 and newer through the Single-window mode checkbox in the Windows menu. In single-window mode, GIMP will put dockable dialogs and images in a single, tabbed image window. The default windows were: Toolbox (left), Main Image (middle), Layers and Brushes (right). In single window mode all three are contained within the Main Image window, which is more consistent with the user experience of Microsoft Windows software.

Customize

• CLICK Windows -> Single Window Mode (you will see a check symbol next to the label once selected)

Usage Help

Gimp works differently than other popular image manipulation software. This is because linux developers can be snobs rather than accommodating. Yes, it hurts linux, but because they think their way is best, we have to learn their way, even if it takes more time and mouse clicks.

• HOWTO: ROTATE LAYER DEGREES --- Arbitrary Rotation: You can access this command from the image menubar through Layer → Transform → Arbitrary Rotation, or by using the keyboard shortcut Shift+R. THEN you might have to: Layer -> Transparency -> Remove Alpha Channel (if you're working with a simple 1 layer image and you want to restore the background.)

• HOWTO: CHANGE COLOR DEPTH --- Color Depth to 1-bit BW: Image -> Mode -> Indexed -> choose "Use black and white 1-bit palette)

• HOWTO: MOVE ACTIVE LAYER IMAGE ONLY --- Moving TEXT or an IMAGE layer: when I attempt to move text or an image in the active layer, gimp either moves the wrong layer or background layer, very stupid and annoying. SOLUTION: Hold SHIFT KEY while using the MOVE TOOL which forces Gimp to work with the current selected layer.

• HOWTO: MOVE SELECTION ONLY --- I select part of an image and when I use the move tool, it moves all of the layer. #$%! SOLUTION: Right click your selection and in the menu, select "Select -> Float." Ctrl+Shift+L Also, this makes it a temporary floating layer, so when you place it, you have to use the layers interface and "Anchor Layer" when done.

• HOWTO: REPLACE COLOR WITH ANOTHER --- In Paint Shop Pro you could select a color with the dropper and exchange it with another. With Gimp it is called the Color Exchange Function. Goto the Menu Colors -> Map -> Color Exchange and then either select the color from the preview picture using the color picker tool or just define the color to replace and the new color manually.

• HOWTO: COPY SELECT, PAST INTO IMAGE AND MOVE TO POSITION --- Use selection tool and create a selection. Press CTRL-C to copy then CTRL-V to paste. Choose the MOVE tool and make sure the MOVE tool is set to MOVE LAYER with Pick a Layer or Guide. Those are under the Tool Options which you should see in an area of the interface on the left center of the screen. Using the move tool you should not be able to move and place the pasted selection. After it is placed you can click anywhere outside of the selection to anchor it down, or CTRL-V again to get another copy of the selection to move and place. Basically, the extra step that PSP users aren't accustomed to involves switching to the MOVE TOOL after pasting.

• HOWTO: EDIT PALETTE IN AN INDEXED IMAGE --- use the Colormap dialog. Upper right of the interface is the dockable dialogs where you will see small tabs each to a dockable dialog. One of the dockable dialogs is Colormap, the tab symbol being four squares of colors. If the dockable dialog is not present goto WINDOWS -> DOCKABLE DIALOGS -> colormap. In the colormap dockable dialog click the color square to edit the color in the palette of the indexed image.