pixedit -- Edit an image.
This task is a screen editor for images. The screen is divided into two windows, the image window and the command window. You edit a image by moving the cursor in the image window with the cursor keys and typing in the new value of the image pixel. The screen scrolls both sideways and up and down as you move the cursor, so all pixels of the image can be reached. Other editing commands are entered in the command window. To switch from the image window to the command window, you press the EXIT key. The default binding for the EXIT key is Control-Z, however, you can change this default, as described later.
After performing a command, the editor returns to the image window, unless the command exits the editor. The most important commands in command mode are `help', `exit', and `quit'. The `help' command displays all the commands and editing key bindings. The `exit' command will get you out of the editor and automatically save the edited image. The `quit' command will get you out of the editor after asking you whether you want to save the image. By default, the editor modifies a copy instead of the original image, so if you quit without saving the image, the original image is still there without any modifications.
Some editing commands are entered from the command window. To get to the command window, press the EXIT key. This key is bound to Control-Z by default. If you enter a blank line, the editor will return to the image window. Some commands take arguments. They can be included when the command is entered, or if they are omitted, the editor will prompt you for their values. When the editor interactively prompts you for a command argument it sometimes displays a default value for the argument. You may edit the default value or use it unchanged. Command names can be abbreviated, as long as the abbreviation is unique. All commands have unique single letter abbreviations.
The following is a list of commands:
- Exit the image editor, saving any changes made to the image.
- format <fmt_string>
- Change the display format of image pixels. The format string may be either a Fortran SPP format string. SPP format strings should start with a "%". Example format strings would be f10.3 for real images or i7 for integer images.
- goto <row> <column> <plane>
- Move the cursor to the indicated pixel. The number of arguments for this command is equal to the dimesionality of the image. This command is the only way to move between planes in a three dimensional image.
- Display online help information for the image editor. The help includes a brief description of each command line command and the key bindings for image editing commands.
- Exit the image editor. If the image has been changed, the image editor will ask you whether to save it before exiting.
The bindings to the image editing keys are read from the edcap file. This is the same file which is used to define the key bindings for the parameter editor and history editor. The edcap file defines key bindings which resemble those of commonly used text editors. Three edcap files are distributed with IRAF. They define key bindings which resemble edt, emacs, and vi. These edcap files are located in the dev$ directory and have the extension ".ed". The appropriate file is chosen according to the value of the environment variable editor. If you want to customize the key bindings of the image editor, copy the appropriate edcap file from the dev$ directory to your home$ directory and edit the second column of the file. The image editor searches your home directory first for the edcap file and if it does not find it, then it searches the dev$ directory.
The image editor also uses the termcap file to determine the screen size and the escape sequences used to modify the screen. There are entries in the termcap file for almost all terminal types. The proper entry is selected according to the environment variable terminal. To change your terminal type or the screen size, use the iraf stty command.
- image [string]
- The name of the image to be edited.
The editor checks for the existence of the image and its access mode before editing. If you do not have write access to a image you can display it using this task by setting readonly to "yes", but you will be unable to overwrite the original image.
- (silent = no) [boolean]
- Disable the bell?
Setting this to "yes" will ring a bell whenever a warning message is displayed.
- (readonly = no) [boolean]
- Use the editor to display the image only?
Set this parameter to "yes" if you want to use the editor to view a image but not to modify it. This parameter prevents you from executing any command that would modify the file.
- (inplace = no) [boolean]
- Overwrite the original image?
Set this to "yes" if you want to edit the image in place. This speeds the editor startup time when editing large images. If readonly is set to "yes" the image is always edited in place.
1. Interactively edit an image called omegcen.hhh.
im> pixedit omegcen.hhh
2. Edit the image in readonly mode.
im> pixedit omegcen.hhh read+