Free Software: Image-Editing with GIMP
GIMP, which stands for GNU Image Manipulation Program, has all the major features of Adobe Photoshop but is available for free under the GNU General Public License. With the GIMP, you can create or open images and manipulate them by cutting, pasting, enlarging, shrinking, flipping, cropping, and much more. You can adjust the color balance, saturation, brightness, and so on to make your colors more vibrant and an image more appealing. The GIMP offers many filters for a multitude of effects. You can layer your images with the GIMP to compose new and extraordinary creations. The GIMP also has a drawing and painting program, plus you can create animations with each frame as a new layer and export them as animations. And that's just the beginning!
Touring the interface
The GIMP has an unusual interface because it doesn't have one major window that fills the screen. Instead, the GIMP has three major floating windows that you can resize and move around your desktop as you like:
- Main Toolbox: This box contains the buttons and controls for the image manipulation tools. When you open the GIMP, the Main Toolbox by default is the only window that appears. When you click on a tool, the options for that tool appear in the pane beneath the tools.
You can undock the Tool Options pane from the bottom of the Main Toolbox; however, redocking it may not be easy to do, and having too many windows open gives a confused and cluttered feel to your desktop.
- Image window: This window, of course, contains your image. To view an Image window, choose File --> New or File --> Open from the menu on the Main Toolbox. You can have as many image windows open as your computer has the memory for. (See the following section for instructions on creating and opening images.)
- Layers window: This window allows you to add new layers, choose which layer you want to make active, hide and lock layers, or apply transparency to any layer. If you want to use pieces of images to create other images — for example to copy and paste someone's face into another picture — then you probably want to use a separate layer for each image in your picture. To view the Layers window, go to the Main Toolbox, and then choose File --> Dialogs --> Layers.
Opening an image file into the image window
To open an image, choose File --> Open and select the filename in the Open Image dialog box. The GIMP can open more than 30 types of image files, including Photoshop files.
Creating a new image window
You may want to cut and paste an image from another application into the GIMP, or you may want to create a new image using the painting and drawing tools. In either case, choose File --> New. The New Image dialog box appears. In it, you can set the following options:
- From Template: Choose from standard resolutions, including standard screen sizes, paper sizes, banner sizes, CD covers, and NTSC, or PAL
- Image Size: The size is shown in pixels as the default, although you can choose other units of measurement from the Unit of Measurement list box. If you choose a unit of measurement other than pixels, you may want to also select a resolution in the Advanced Options, since resolution is measured in pixels and not inches or other units of measurement.
- If an image resides in the clipboard, you may find that the image size in the Create a New Image dialog box is automatically set for that image, but this is not always the case.
- Portrait or Landscape: Click either the Portrait button or the Landscape button to exchange the width and the height, if you want. Landscape makes the width larger and Portrait makes the height larger.
- Advanced Options: Click Advanced Options to reveal more options.
• X resolution and Y resolution: These options are set automatically if you choose a template or if you choose your image size in Pixels or if an image is copied into the clipboard. You may want to set the resolution, for example, if you set your image size in inches and you want to print your image at a high resolution, such as 600 dpi (dots per inch) or even higher. You can set the resolution for the values that you want. The Image Size (in pixels) changes to reflect the higher resolution. (Pixels are generally square for computer graphics work, so you'll probably want the X and Y values to be the same, otherwise the proportions of your image may be affected.)
• Colorspace: Choose RGB for color or Grayscale for black and white.(RGB stands for Red Green Blue, which when combined in various proportions can create all the colors of the rainbow.)
• Fill with: Notice that in the Main Toolbox are two squares near the bottom of the upper pane. These are the foreground and background colors. For this option, choose Foreground if you want the new image to be filled with the foreground color. Or you can choose Background, White, even Transparent if you want a transparent background.
• Image Comment: Add a comment about the image, if you want. This will be embedded in the file but won't be visible when the image is viewed.
Click OK and a new Image window appears. If you want to paste an image that you copied from another application, choose Edit --> Paste.