The most obvious is to open it using a menu, by choosing File → Open from either the Toolbox menu or an image menu. This brings up a File Chooser dialog, allowing you to navigate to the file and click on its name. This method works well if you know the name of the file you want to open, and where it is located. It is not so convenient if you want to find the file on the basis of a thumbnail.

Figure 5.4.  The “File Open” dialog.

GIMP 2.2 introduced a new File Chooser that provides several features to help you navigate quickly to the file you are looking for. Perhaps the most important is the ability to create “bookmarks” for folders that you use often. Your list of bookmarks appears on the left side of the dialog. The ones at the top ( “Home”, “Desktop”, etc) come automatically; the others you create using the “Add” button at the bottom of the list. Double-clicking on a bookmark takes you straight to that directory.

At the center of the dialog appears a listing of the contents of the selected directory. Subdirectories are shown at the top of the list, files below them. By default all files in the directory are listed, but you can restrict the listing to image files of a specific type using the File Type selection menu that appears beneath the directory listing.

When you click on a file entry in the listing, if it is an image file, a preview will appear on the right side of the dialog, along with some basic information about the properties of the image. Note that previews are cached when they are generated, and there are some things you can do that may cause a preview to be incorrect. If you suspect that this may be happening, you can force a new preview to be generated by holding down the Ctrl key and clicking in the Preview area.

One thing that strikes many people when they first see the File Open dialog is that there is no way to enter the name of the file using the keyboard. Actually this can be done, but the feature is a bit hidden: if you type Ctrl-L with the dialog focused, an "Open Location" dialog pops up, with a space to type the file name. This dialog is described in more detail below.

Note

In the great majority of cases, if you select a file name from the list, and click the “Open” button in the lower right corner or the dialog, GIMP will automatically determine the file type for you. On rare occasions, mainly if the file type is unusual and the name lacks a meaningful extension, this may fail. If this happens, you can tell GIMP specifically what type of file it is by expanding the “Select File Typ” option at the bottom of the dialog, and choosing an entry from the list that appears. More commonly, though, if GIMP fails to open an image file, it is either corrupt or not in a supported format.

If instead of a file name, you have a URI (i.e., a web address) for the image, you can open it using the menu, by choosing File → Open Location from either the Toolbox menu or an image menu. This brings up a small dialog that allows you to enter (or paste) the URI.

Figure 5.5.  The “Open Location” dialog.

The “Open Location” dialog.

If the image is one that you previously created using GIMP, perhaps the easiest way to open it is from the menu, using File → Open Recent. This gives you a scrollable list of the images you have most recently worked on in, with icons beside them. You need only select the one you want, and it will be opened.

If you have associated the file type of the image with GIMP, either when you installed GIMP or later, then you can navigate to the file using a file manager (such as Nautilus in Linux, or Windows Explorer in Windows), and once you have found it, double-click on the icon. If things are set up properly, this will cause the image to open in GIMP.

Alternatively, once you have found the file, you can click on its icon and drag it into the GIMP Toolbox. (If instead you drag it into an existing GIMP image, it will be added to that image as a new layer or set of layers).

For many applications, you can click on a displayed image (a full image, not just a thumbnail) and drag it into the GIMP toolbox.

For some applications, if the application gives you a way of copying the image to the clipboard (the Print Screen key lets you copy the screen into the clipboard), you can then open the image in GIMP by choosing File → Acquire → Paste as New from the Toolbox menu. Support for this is somewhat variable, however, so your best bet is to try it and see whether it works.

In Linux, you might want to take a look at a program called gthumb, an image-management application that in several ways nicely complements GIMP. In gthumb, you can cause an image to open in GIMP either by right-clicking on the icon and selecting GIMP from among the list of options, or by dragging the icon into the GIMP Toolbox. See the gthumb home page for more information. Other similar applications : gqview, xnview