Wikipedia:How to use the GIMP
From Wikipedia, the free encyclopedia
The GIMP is a free tool for manipulating images, especially photos (bitmaps as opposed to vectors). It also has some powerful functions for dealing with (other) web related graphics too.
As for most other powerful image manipulators, such as Photoshop or Paint Shop Pro, a lot of tutorials for this package have been written that can be found on the web using any decent search engine. Often the tutorials can be used interchangeably: a moderately advanced GIMP user can follow Photoshop tutorials as if they were written for the GIMP, and the other way around, except of course where the tutorial uses a feature that one of the programs does not support.
One thing that should be noted by those who want to dive in right away: right clicking an image window will conjure up a menu that gives access to most of the GIMP's powerful filters and tools.
See also: Wikipedia:Graphics tutorials
Contents |
[edit] The GIMP toolbox
To load an image, use the File, Open menu.
To take a screenshot, use the File, Acquire, Screenshot menu.
[edit] Editing an image
This shows a typical image editing window in the GIMP (this is version 1.2, more recent versions will have a set of menus at the top of the image window)
Right-click on the image to access the menus. For example, Right-click, File, Save is used to save the image. PNG or JPEG formats are available for use in Wikipedia.
Image, Canvas size is used to modify the area available to draw in, but does not attempt to scale the image.
Image, Scale image is used to change the size of the image, for example to create thumbnail images.
The Crop tool on the toolbox can be used to select an area of the original image for keeping, and discard the rest.
To remove a section of image, just select it (using one of the select tools) and press Control-K ("kill"). This will either erase the selection to the background colour, or to transparency if the image supports it
[edit] Colours and transparency
Image, Mode, Indexed can be used to reduce the number of colours in the image, to make the filesize smaller for internet use. (This reduction in colours is not required if you intend to save as a JPEG file)
Similarly, Image, Mode, RGB makes the full range of colours available, and is required for many of GIMP's tools and filters to work.
The Image, Alpha menu is used to add or remove transparency support to an image. (Transparency is available in PNG files, but not in JPEG)
[edit] Saving the image
Right-click, File, Save is used to save the image. A filetype can be selected (PNG, JPEG, etc.) from the dropdown list, or the default action is to use whatever extension was typed (specifying "image.jpg" causes it to save a JPEG file)
After the filename is specified, there is an additional dialog box specific to each filetype. For example, a JPEG image will ask you for the compression level, and it can be useful to adjust this until the image is a reasonable filesize.
JPEG is typically used for photographs, while PNG is used for screenshots and computer graphics.
[edit] GIF images
By default, the GIMP assumes that you do not have the Unisys patent license required to save GIF images, so it will not be possible to save as GIF. This is available as a separate download if required, although PNG will usually suffice. The patent has expired in many countries, so check your country's patent database before downloading the GIF plug-in.
[edit] Further reading
- User Manual for GIMP 2 is available online in several languages.
- Grokking the GIMP is available both online and in print form, and is still a good resource for GIMP image editing even though it was written for GIMP version 1.2.
- GIMPshop.com - site for downloading GIMPshop, a modified GUI for GIMP.
